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Objective: To investigate the pollution levels and influencing factors of polybrominated diphenyl ethers (PBDEs) in household dust in five cities in northern China. Methods: Based on the "Chinese Indoor Environment and Health Surveillance" project carried out by the National Institute of Environmental Health, Chinese Center for Disease Control and Prevention in 2018-2019, during the warm season (April 2018 to September 2018) and the cold season (November 2018 to March 2019), Lanzhou in Northwest China, Shijiazhuang in North China, Panjin in Northeast China, Luoyang in Central China, and Qingdao in East China were selected as the research sites. A total of 87 families were recruited to study residences in real-life scenarios. At the same time, dust samples were collected to detect the concentration of PBDEs. The level of household environmental indicators was measured, and the residential building characteristics and family behavior habits were collected through questionnaires. A total of 142 valid dust samples and 140 valid questionnaires were obtained. The differences in PBDE concentrations across seasons, wind zones, residential building characteristics, and family habits were analyzed. The exploratory factor analysis was performed to investigate the possible sources of PBDEs, and multivariate linear regression was used to explore the factors influencing PBDEs in household dust. Results: The M ( Q 1, Q 3 ) of total PBDE concentrations in 142 household dust samples in five cities was 144.51 (106.61, 222.65) ng/g in the warm season and 145.10 (98.57, 180.65) ng/g in the cold season, respectively. There were seasonal differences in the concentration of ∑ 12 PBDEs in Luoyang and Shijiazhuang ( P <0.01). The concentration of BDE-71 was highest among PBDE homologues, followed by BDE-66 and BDE-47. Three factors were extracted by exploratory factor analysis in the warm season, and the cumulative variance contribution rate was 67.90%. The multivariate linear regression showed that the house completion less than ten years [ β (95% CI ): 0.186 (0.013, 0.359)], infrequent home cooking [ β (95% CI ):-0.342 (-0.570, -0.114)], and increased residential PM 10 concentration [ β (95% CI ): 0.001 (0.000, 0.002)] during the warm season, as well as the house far from driveway [ β (95% CI ): 0.093 (0.013, 0.172)], house area less than 90 m 2 [ β (95% CI ):-0.138 (-0.264, -0.013)], and lower residential xylene concentration [ β (95% CI ):-0.006 (-0.011, -0.001)] during the cold season might be related to the elevated concentrations of ∑ 12 PBDEs in household dust. Conclusion: The pollution of PBDEs in household dust in five northern cities is at a medium to high level. Years of house completion, frequency of cooking at home, residential PM 10 concentration, distance from house to driveway, house area, and residential xylene concentration may influence household PBDE concentrations.

Objective: To investigate the effect and potential mechanism of exposure to 20 nm polystyrene nanoplastics (PS-NPs) on lipid metabolism in mice liver. Methods: An animal experimental model was designed, which was completed from September 2022 to July 2023 on the exposure omics platform of the School of Public Health at Capital Medical University and the Key Laboratory of Environment and Population Health at the Chinese Center for Disease Control and Prevention.1 mg/kg and 10 mg/kg PS-NPs tail vein mice exposure models were constructed. After exposure 7 d, serum was collected to measure the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and air flow assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI) analysis were used to analyze the mRNA levels of fatty acid esterification related genes ( Dgat1 and Dgat2 ) and lipid transport related genes ( ApoB , Cd36 , ApoE and Mttp ) and metabolites' spatial changes in liver tissue. In vivo imaging system (IVIS) and tissue shake sections were employed to observe the fluorescence biological distribution of PS-NPs. t -test or one-way ANOVA was used to explore the difference between groups. Results: The serum ALT levels were (83.97±4.58), (91.17±13.69) and (142.43±6.09) U/L in the control group, 1 mg/kg PS-NPs exposure group and 10 mg/kg PS-NPs exposure group respectively ( F =37.281, P <0.05). The relative mRNA levels of Dgat1 , Dgat2 , ApoB , Cd36 and ApoE were (1.49±0.63, 2.53±0.32, 2.45±0.54), (1.07±0.38, 1.86±0.83, 2.23±0.73), (1.01±0.13, 1.58±0.43, 2.03±0.52), (1.01±0.14, 1.55±0.37, 1.52±0.51), (1.01±0.17, 2.11±0.27, 2.39±0.93) in these three groups respectively. The differences were statistically significant ( F =11.54, 6.95, 14.90, 5.98 and 14.68, P <0.05). AFADESI-MSI analysis found that PS-NPs exposure led to a significant decrease in the levels of glutarylcarnitine and O-Linoleoylcarnitine ( t =4.12 and 3.35, P <0.05), which were associated with lipid beta oxidation. The content of triglycerides (TG) (m/z 921.726 4, t =8.69, P <0.05; m/z 919.711 4, t =3.20, P <0.05), phosphatidylic acid (PA) (m/z 895.712 3, t =3.60, P <0.05; m/z 821.526 6, t =3.36, P <0.05), lysophosphatidylcholine (LysoPC) (m/z 560.310 6, t =3.35, P <0.05; m/z 582.295 3, t =6.28, P <0.05), phosphatidylcholine (PC) (m/z 778.533 9, t =3.53, P <0.05; m/z 804.549 6, t =3.60, P <0.05; m/z 820.523 1, t =3.37, P <0.05), phosphatidylethanolamine (PE) (m/z 772.523 3, t =3.08, P <0.05) showed a significant increase in the PS-NPs exposure group. In vivo and in vitro imaging and in situ cell localization revealed that PS-NPs were mainly enriched in hepatic stellate cells and hepatic Kupffer cells in liver tissue. Conclusion: Exposure to PS-NPs induces disorder of liver lipid metabolism, which may be related to the accumulation of PS-NPs in hepatic stellate cells and hepatic Kupffer cells, providing basis for searching early biomarkers of PS-NPs exposure and further mechanism research.

Objective: To investigate the distribution and exposure levels of pesticides in raw water and drinking water in China, as well as to assess the potential health risks associated with long-term consumption., Methods: A total of 83 typical water plants were selected in key river basins in China to collected samples of the raw water, finished water, and tap water. The online-solid phase extraction coupled with liquid chromatography-tandem mass spectrometry method was used to determine 13 pesticides, including acetochlor, atrazine, dimethoate, malathion, carbofuran, dichlorvos, chlorpyrifos, parathion, trifluralin, isoprothiolane, simetryn, methyl parathion, and metalaxyl, as well as 6 environmental metabolites, including carbendazim, malaoxon, 3-hydroxycarbofuran, deethyl atrazine, deisopropyl atrazine and hydroxy atrazine. The carcinogenic and non-carcinogenic risks of these pesticides were assessed., Results: The concentrations of total amount of pesticides in the samples ranged from 0.1 ng/L to 1299.4 ng/L, with a median value of 64.7 ng/L. The detection rates of 5 pesticides or their metabolites exceeds 80%, namely acetochlor, atrazine, hydroxyl atrazine, deethyl atrazine, and metalaxyl. More than 6 pesticides or their metabolites were detected in 77.7% of the total 498 samples. The total concentration of pesticides during the wet season ranged from 1.1 ng/L to 1299.4 ng/L, with a median of 69.2 ng/L and a median average daily dose of 2.3 ng/(kg·d). The total concentration of pesticides in the dry season samples ranged from 0.1 ng/L to 543.5 ng/L, with a median of 60.2 ng/L and a median average daily dose of 2.0 ng/(kg·d). Among the 498 samples, the maximum carcinogenic risk of dichlorvos was 2.0×10~(-7), and the maximum carcinogenic risk of trifluralin was 1.1×10~(-10). The non-carcinogenic HI of 19 pesticides and metabolites pesticides was ≤6.0×10~(-3). Among them, the maximum HI of the middle route of the South to North Water Diversion Project, the lower reaches of the Yellow River, the eastern route of the South to North Water Diversion Project, the Liaohe River, and the Songhua River basin was 2.0×10~(-3)-6.0×10~(-3), while the HI of other basins was less than 1.0×10~(-3)., Conclusion: Different concentrations of pesticides have been detected in raw water, finished water, and tap water of key river basins in China, with the highest total concentration of detected reaching 1299.4 ng/L. The carcinogenic risk was lower than 10~(-6) and the non-carcinogenic hazard index of 19 pesticides was less than 1, and both below the acceptable level. Because of the universality and diverse occurrence of these pesticides in drinking water, long-term exposure to pesticides is still a concern.

Objective: To explore the characteristics of adverse drug reactions during the 24-week therapy with delamanid-containing regimen for patients with multidrug-resistant and rifampicin-resistant pulmonary tuberculosis (MDR/RR-PTB). Methods: The prospective multicenter study was conducted from June 2020 to June 2023. A total of 608 eligible patients with MDR/RR-PTB were enrolled in 26 tuberculosis medical institutions in China including 364 males and 79 females, aged 39.6(19.0-68.0) years. Patients were treated with chemotherapy regimens containing delamanid. Patients were closely supervised during treatment of medication, and all adverse reactions occurring during treatment were monitored and recorded. The clinical characteristics of adverse reactions were evaluated by descriptive analysis. Chi-square test and multivariate logistic regression were used to analyze the related factors of QTcF interval prolongation (QT corrected with Fridericia's formula). Results: Of the 608 patients enrolled in this study, 325 patients (53.5%) reported 710 adverse events within 24 weeks of treatment. The top 6 most common complications were hematological abnormalities (143 patients, 23.5%), QT prolongation (114 patients, 18.8%), liver toxicity (85 patients, 14.0%), gastrointestinal reaction (41 patients, 6.7%), peripheral neuropathy (25 patients, 4.1%) and mental disorders (21 patients, 3.5%). The prolongation of QT interval mostly occurred in the 12th week after the first dose of medication. Serious adverse reactions occurred in 21 patients (3.5%). There were 7 patients (1.2%) with mental disorders, including 2 patients (0.3%) with severe mental disorders. Conclusions: The safety of dalamanid-based regimen in the staged treatment of MDR/RR-PTB patients was generally good, and the incidence of adverse reactions was similar to that reported in foreign studies. This study found that the incidence of QT interval prolongation in Chinese patients was higher than that reported overseas, suggesting that the monitoring of electrocardiogram should be strengthened when using drugs containing delamanid that may cause QT interval prolongation.

Recent epidemiological studies have increasingly found that pregnant women who are exposed to air pollutants (for example airborne particulate matter, nitrogen oxides, ozone, and sulfur dioxide) increase the risk of various birth defects in their offspring, such as congenital heart disease, neural tube defects, cleft lip and palate, and hypospadias. Hypospadias not only impairs the sexual function of infants but also causes major social and psychological problems during their growth period, therefore, the prevention and treatment of hypospadias infant carry substantial public health importance. However, the association between prenatal exposure to air pollution and hypospadias remains controversial. The study reviews the epidemiological research progress and potential biological mechanisms of prenatal maternal exposure to air pollutants such as particulate matter, nitrogen oxides, ozone, sulfur dioxide, and the risk of hypospadias in offspring. The study also summarizes the limitations of previous research and looks forward to future research directions, to provide scientific evidence for creating a healthy living environment for pregnant women, and reducing the risk of hypospadias in offspring.

Objective: To compare the differences in estimated food, energy, and nutrient intakes between the consecutive 3 days 24-hour dietary recall(24HR)(referred to as the 3-day method) and consecutive 2 days 24HR(referred to as the 2-day method) to provide a basis for the use of consecutive 2 days 24HR in China nutrition surveillance., Methods: Using objective sampling to select participants in northern and southern provinces, dietary data were obtained through consecutive 3 days 24HR, and the average intakes of food, energy and nutrients were calculated for three days from Thursday to Saturday and two days on Friday and Saturday, respectively. The 3-day method was considered as the reference standard method to evaluate the performance of the 2-day method for estimating food, energy and nutrient intakes., Results: Among 778 participants aged 18-60 years in urban and rural areas of two provinces, the errors of the mean and median of 2-day method for estimating the intake of four major food categories less than 6% compared with the 3-day method, and there were significant equivalencies(P&lt;0.025) and no significant differences in four major food categories group(P&gt;0.05). Of the 24 food groups estimated by the 2-day method, 17 had mean errors within 5%, the largest error was in animal offal(13.45%) and the smallest in fruit(0.15%), and there were significant equivalencies(P&lt;0.025) and no significant differences in seven food groups(P&gt;0.05). For energy and nutrients, the mean and median errors of energy were less than 0.5% and there were significant equivalencies(P&lt;0.025) and no significant differences for energy(P&gt;0.05). Among the 25 nutrients, except sodium, iodine and vitamin E, the mean and median errors of the other 22 nutrients were less than 5%, and there were significant equivalencies(P&lt;0.025) and no significant differences in 16 nutrients(P&gt;0.05)., Conclusion: There was little difference between the two survey method in assessing the intake of high consumption frequency foods, energy and most nutrients at group level, the 2-day method can be used as an alternative to the 3-day method to collect dietary intake data with high consumption rates in the population.

Objective: To describe and analysis the detection rate of high normal blood pressure and high blood pressure among Chinese children and adolescents aged 7-17 years from 2016 to 2017 according to the clinical practice guideline for screening and management of high blood pressure in Children and Adolescents published by the American Academy of Pediatrics(the AAP reference), the international blood pressure references among Children and Adolescents aged 6 to 17 years(the international reference), health industry standard of the People&apos;s Republic of China "Reference of screening for elevated blood pressure among children and adolescents aged 7 to 18 years(WS/T 610-2018)"(the industry reference) and updating blood pressure references for Chinese children aged 3 to 17 years(the guideline reference)., Methods: Data was from the China Nutrition and Health Surveillance of Children and Lactating Women(2016-2017), in which the multistage stratified whole group random sampling method was used to draw participants from 275 surveillance sites in 31 provinces(autonomous regions and municipalities). In total, 67 231 participants were included according to the inclusion and exclusion criteria. Blood pressure was measured three times by trained staff using a validated oscillometric blood pressure monitor at the same point. The average blood pressure was calculated for the three measurements for SBP and DBP. To match the sampling design methodology, all values were weighted to represent the total population of Chinese children and adolescents 7-17 years of age considering sampling weights for each stratification based on the sixth population census data provided by the National Bureau of Statistics., Results: The detection rate varied greatly under different references. The detection rate of high normal blood pressure was ranked from high to low according to the AAP reference(20.15%) &gt; the guideline reference(17.29%) &gt; the industry reference(13.14%) &gt; the international reference(12.66%); the detection rate of high blood pressure in descending order is the guideline reference(24.31%) &gt; the international reference(21.34%) &gt; the AAP reference(20.59%) &gt; the industry reference(19.96%)., Conclusion: Although the consistency between the AAP references and international references and our national two references were medium to high, the difference in detection rate obtained by analysis was large. Considering the differences of demographic characteristics in the reference population, caution should be taken when applying foreign references to judge the blood pressure status of children and adolescents in China.

Objective: To investigate the black carbon (BC) pollution in the indoor air of typical residential houses in urban areas of Beijing, and to explore the relationship between indoor and outdoor BC concentrations as well as the main influencing factors., Methods: The indoor and outdoor PM&#95;(2.5) samples were collected simultaneously from 33 apartments in the urban areas of Beijing during both the heating season (January to March) and the non-heating season (June to August) in 2016. Subsequently, optical method were employed to analyze BC concentrations in PM&#95;(2.5)samples. The Spearman correlation coefficient (r&#95;s) and the indoor/outdoor (I/O) ratio of BC concentrations were both calculated to characterize the relationship between indoor and outdoor BC concentrations. The factors may influence indoor BC pollution was collected through a questionnaire, including the basic characteristics of the residential buildings and households, smoking, cooking, window opening behavior, the use of air conditioner or air purifier and so on. Additionally, a linear mixed-effects model or multiple linear regression model was applied to identify the main factors influencing the I/O ratio., Results: The(M(P25, P75)) concentrations of indoor and outdoor BC for season-pooled analysis were2.84 (2.59, 3.26)μg/m~3 and 3.08 (2.90, 3.63)μg/m~3, respectively. There were significant seasonal differences in both indoor and outdoor concentrations (P&lt;0.05), with higher levels observed during the heating season compared to the non-heating season. There was a strong correlation between indoor and outdoor BC (r&#95;s=0.74). The correlation during the heating season (r&#95;s=0.78) was stronger than that during the non-heating season (r&#95;s=0.44). The ■ of I/O ratio was 0.90±0.11, with 93.5%(29/31)and 86.7%(26/30) of I/O ratios being less than 1 during the heating season and non-heating season, respectively. Statistical analysis also showed that outdoor BCconcentrations were significantly higher than indoors (P&lt;0.05). In season-pooled analysis, the result of the linear mixed-effects model showed that window opening duration was the most important factor affecting the I/O ratio, explaining 21.3%of the total variation. The I/O ratio increased with longer window opening duration. In season-specific analysis, the characteristics of residential buildings (including building age and floor level) and window opening duration were the main factors affecting the I/O ratio during the heating season and non-heating season, respectively in 2016., Conclusion: Residents in the urban areas of Beijing experienced relatively high indoor levels of BCpollution, but lower than the outdoor concentration during the same period in 2016. The window opening and the characteristics of residential buildings were the most important factors affecting the I/O ratio of BC.

Objective: To develop a prediction tool for 6-year incident risk of frailty among Chinese older adults aged 65 years or above. Methods: Data from the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2018 was used, including 13 676 older adults aged 65 years or above who were free of frailty at baseline. Key predictors of frailty were identified via the least absolute shrinkage and selection operator (LASSO) method, and were thereafter used to predict the incident frailty based on the Cox proportional hazards regression model. The model was internally validated by 2 000 Bootstrap resamples and evaluated for the performance of discrimination and calibration using the area under the receiver operating characteristic curve (AUC) and calibration curve, respectively. The net benefit of the developed prediction tool was evaluated by decision-curve analysis. Results: The M ( Q 1 , Q 3 ) age and follow-up time of the participants were 81.0 (71.0, 90.0) years and 6.0 (4.1, 9.2) years, respectively. A total of 4 126 older persons (30.2%) were recorded with frailty incidents during the follow-up, with the corresponding incidence density of 41.8/1 000 person-years. A total of 15 key predictors of frailty were selected by LASSO, namely, age, sex, race, education years, meat consumption, tea drinking, performing housework, raising domestic animals, playing cards or mahjong, and baseline status of visual function, activities of the daily living score, instrumental activities of the daily living score, hypertension, heart disease, and self-rated health. The prediction model was internally validated with an AUC of 0.802, with the max Youden's index of 0.467 at a risk threshold of 19.0%. The calibration curve showed high consistency between predicted probabilities and observed proportions of frailty events. The decision curve indicated that higher net benefits could be obtained via the prediction model than did strategies based on intervention in all or none participants for any risk threshold less than 59%, and the model-based net benefit was estimated to be 0.10 at a risk threshold of 19.0%. Conclusions: The herein developed 6-year incident risk prediction model of frailty, based on easily accessible questionnaires and physical examination variables, has good predictive performance. It has application potential in identifying populations at high risk of incident frailty.

Objective: To explore the impact of whole blood organophosphate esters (OPEs) flame retardant exposure on thyroid function-related hormones in healthy older adults. Methods: In this panel study, five repeated population-based epidemiological surveys and biological sample collection were conducted from September 2018 to January 2019, with 76 healthy older adults aged 60-69 years in the Dianliu Community of Jinan, Shandong Province. Information on the sociodemographic characteristics, diet, and health status of the respondents was systematically gathered through questionnaires and physical examinations. Fasting venous blood was collected to determine the levels of OPEs, thyroid-stimulating hormone (TSH), triiodothyronine (T 3 ), and thyroxine (T 4 ). A linear mixed-effects model was used to analyze the impact of OPEs exposure on thyroid function-related hormones in healthy older adults. Results: Each of the 76 subjects participated in at least two follow-up visits, resulting in a total of 350 person visits. The age of the study participants was (65.07±2.76) years, with 38 participants of both sexes. A total of eight OPEs were included with a detection rate exceeding 50%, and the M ( Q 1 , Q 3 ) for ∑OPEs was 3.85 (2.33, 5.74) ng/ml, with alkyl-OPEs being the major type of OPEs with an M ( Q 1 , Q 3 ) of 1.27 (0.64, 2.50) ng/ml. The M ( Q 1 , Q 3 ) for TSH, T 3 , and T 4 was 3.74 (2.55, 5.69) μIU/ml, 1.32 (1.10, 1.60) ng/ml, and 45.04 (36.96, 53.27) ng/ml, respectively. Linear mixed-effects model showed that TSH was significantly decreased by 9.93% (95% CI :-15.17%, -4.36%) and 11.14% (95% CI :-15.94%, -6.06%) in older adults for each quartile level increase in TnBP and TEHP exposures, respectively. Gender-stratified analysis indicated that TEHP exposure was negatively associated with TSH levels in male older adults, whereas a decrease in TSH levels among female older adults was associated with TnBP exposure. Conclusion: Exposure to whole blood OPEs is associated with decreased TSH levels among healthy older adults, with notable gender differences.

Objective: To explore the implementation strategies for promoting healthy longevity among the elderly population in China based on the Delphi method. Methods: Through literature review and expert discussion, a framework for implementation strategies to achieve healthy longevity among the elderly was determined, and a preliminary checklist of implementation strategies was developed. The Delphi method was employed from August to December 2022, inviting 25 experts from various disciplines such as clinical medicine, public health, basic research, and the elderly care services industry. Experts were sent consultation questionnaires via email to assess the importance, feasibility, judgment basis and familiarity of each implementation strategy. Active coefficient, authority coefficient, and harmony coefficient were analyzed to ultimately determine the important and feasible implementation strategies for healthy longevity that were suitable for the Chinese elderly population. Results: The expert active coefficients of the two rounds were 96.00% (24/25) and 79.17% (19/24). The authority coefficients were (0.76±0.19) and (0.77±0.17). The average scores of importance were (4.32±0.84) and (4.36±0.82), and the corresponding scores of feasibility were (3.72±1.04) and (3.80±0.92). The harmony coefficients for the importance score were 0.269 ( χ 2 =594.084, P <0.001) and 0.159 ( χ 2 =193.624, P <0.001). The harmony coefficients for feasibility scores were 0.205 ( χ 2 =452.008, P <0.001) and 0.167 ( χ 2 =202.878, P <0.001). The final eight implementation strategies were identified after two rounds of consultation. Conclusion: Through two rounds of Delphi consultations, eight important and feasible implementation strategies for promoting healthy longevity that are suitable for the Chinese context have been proposed.

Objective: To investigate the association of urinary cadmium levels with peripheral leukocyte classification counts among middle-aged and older adults aged 40 to 89 years in selected areas of China. Methods: The research was based on the survey of the impact of soil quality of agricultural land on human health in typical areas conducted in 2019-2020. A total of 5 600 middle-aged and older adults aged 40 to 89 years were included by using a multi-stage stratified random sampling method. Baseline characteristics of the subjects were collected and physical examinations were performed. Random midstream urine was collected to measure urinary cadmium and urinary creatinine and fasting venous blood was collected to measure the leukocyte count, neutrophil count, lymphocyte count, monocyte count and eosinophil count. The linear mixed effect model was used to analyse the association of urinary cadmium levels with leukocyte classification counts, and the dose-response relationship between them was analyzed by using the restricted cubic spline (RCS) function. Results: The age of the subjects was (63.17±12.02) years; 2 851 (50.91%) were males; and the M ( Q 1 , Q 3 ) of urinary creatinine-corrected urinary cadmium levels was 2.69 (1.52, 4.69) μg/g·creatinine. After adjusting for confounding factors, the results of linear mixed effects model analysis showed that for each 1-unit increase in urinary creatinine-corrected urinary cadmium level, the percentage change [% (95% CI )] of leukocyte count and lymphocyte count was -1.70% (-2.61%, -0.79%) and -1.57% (-2.86%, -0.26%), respectively. RCS function showed a negative linear relationship between urinary creatinine-corrected urinary cadmium levels and leukocyte counts and lymphocyte counts, respectively (all P non-linear >0.05). Conclusion: Urinary cadmium levels are negatively associated with leukocyte count and lymphocyte count among middle-aged and older adults aged 40 to 89 years in selected areas of China.

In recent years, the high temperature and heatwaves have seriously affected the health of Chinese residents, and there is an important need for public health protection guidelines for high temperature and heatwaves in China. The National Bureau of Disease Control and Prevention has organized experts to fully investigate the evidence from epidemiological research on the health of populations in high temperature and heatwaves globally and in China, analyze the health hazards and protection needs of different populations, and put forward practical and effective individual protection measures and health recommendations. For this reason, the "Guideline for Public Health Protection against High Temperature and Heatwaves" (referred to as the "Guideline") was officially issued in June 2023. This article interprets the background and significance of the Guideline, the principles of compilation, the main considerations, the main contents, the implementations and promotions and other aspects, to improve the understanding of the content of the Guideline and strengthen the publicity and implementations.

Objective: To analyze the change in human resources within China's Centers for Disease Control and Prevention (CDC) from 2010 to 2020. Methods: The self-reported information from provincial, prefectural (city), and county (district) levels of China's CDC, covering employee counts, staff composition, professional qualifications, educational backgrounds, technical titles, and tenure, were extracted from the China Disease Prevention and Control Information System. The demographic context was provided by the annual population figures from the China Statistical Yearbook (2010-2020). The profile of CDC personnel was described, and the average annual percentage rate change (AAPC), average annual percentage rate change (APC), human resource agglomeration degree (HRAD) and the difference between HRAD and population agglomeration degree (PAD) were calculated. The Joinpoint regression model was used to analyze the time trend. Results: The decade under review witnessed a net increase of 17 300 active and 18 300 enrolled personnel in the CDC, surpassing the national population growth rate with AAPCs of 0.93% and 1.03%, respectively. This upward trajectory was statistically significant ( P <0.05). The ratio of disease control personnel per 10 000 population escalated from 1.14 to 1.21. An initial decline in active CDC workforce density (from 1.31 to 1.27 per 10 000 population between 2010 and 2017) was followed by an increase (from 1.28 to 1.37 between 2018 and 2020), with APCs of -0.40% and 3.73%, respectively. The proportion of professional and technical staff in 2019 was highest in the eastern region (86.01%), followed by the western (83.75%) and central regions (79.54%). The period also saw an enhancement in the average academic degree (from 1.91 to 2.43 points) and professional title scores (from 1.39 to 1.53 points) of CDC personnel. While the average tenure in the eastern and western regions showed a slight decline, the central region experienced an increase, with HRAD values indicating a higher concentration in the eastern and central regions compared to the western region. The HRAD-PAD discrepancy revealed a negative value in the eastern region, nearing zero in the central and western regions. Conclusion: Between 2010 and 2020, China's CDC experienced notable growth in human resources and underwent structural optimization, albeit with significant regional disparities in concentration.

Objective: To explore a definition of healthy longevity in the Chinese population based on the Delphi method. Methods: Through a comprehensive literature review and expert consultation, the dimensions in the definition of healthy longevity were identified, and a preliminary list of questions was created. Experts in clinical medicine, public health, basic research, and the elderly care service industry, who had been working in the field of geriatric health for at least 5 years, were invited to participate in the Delphi survey from August to December 2022. The survey questionnaires were administered via email in two rounds, and experts were asked to select the optimal options from the provided questions. The active coefficients were expressed by the response rate, and a consensus was reached when the largest number of experts agreed for single-choice questions and more than 70% agreed for multiple-choice questions. Results: In the two rounds, the active coefficients were 96.00% (24/25) and 79.17% (19/24), respectively, and a consensus was finally reached on nine items, including age, physical health, common metabolic indicators, mental health, cognitive function, functional ability, social activity, self-rated health, and subjective well-being. Following discussions among the research team and experts, a final definition of healthy longevity was determined. Healthy longevity could refer to a state of good physical, psychological, cognitive function and social adaptation, as well as subjective well-being, in individuals aged 90 and above. Specifically, individuals with healthy longevity should be free from diseases associated with high disability rates and mortality, such as stroke, cancer, and Parkinson's disease. They should also maintain reasonable levels of common non-communicable disease indicators, such as blood pressure and blood glucose, and exhibit favorable mental health and cognitive function using validated measurement tools. In addition, individuals with healthy longevity should engage in social interactions with friends and relatives, care for family members, and go out to do things. Meanwhile, with the ability to complete the visual and hearing functions of daily life and communication, and the ability to complete basic activities such as walking, eating, bathing, toileting, dressing, continence of urination, and bowel movement independently, they could rate themselves to be in good health and experience a relatively high level of life satisfaction. Conclusion: A definition of healthy longevity in the Chinese population is established through the two-round Delphi consultation.

Objective: To estimate the usual vitamin intake and the prevalence of inadequate intakes among Chinese adults in 2015, and to provide a scientific basis for developing nutrition intervention strategies and measures for target populations., Methods: Data was drawn from the Chinese Nutrition and Health Surveillance 2015-2017, a nationally representative cross-sectional study. The multistage stratified whole-group random sampling method was used to draw participants from 298 surveillance sites in 31 provinces(autonomous regions and municipalities). Participants with no available information or abnormal energy intake were excluded, and finally, a total of 72 231 participants aged 18 years and older were included in the current study. The dietary data of the participants were collected by the 24-hour dietary recall method combined with the condiment weighing method for three consecutive days. The National Cancer Institute method was used to estimate the distribution of the usual intake of vitamin B&#95;1(thiamine), vitamin B&#95;2(riboflavin), niacin, vitamin C(ascorbic acid), and vitamin E(tocopherol), and the prevalence of inadequate intake was evaluated based on estimated average requirement or adequate intake from the Chinese Dietary Reference Intakes 2023., Results: The usual intake of vitamin E, vitamin C, vitamin B&#95;1, vitamin B&#95;2 and niacin were 27.93 mg/d, 77.67 mg/d, 0.78 mg/d, 0.62 mg/d and 13.15 mg/d, respectively. The prevalence of inadequate intake was, in descending order, vitamin B&#95;2(95.98%), vitamin B&#95;1(86.73%), vitamin C(63.70%), niacin(39.81%), and vitamin E(21.17%). The prevalence of inadequate vitamin E, vitamin C, vitamin B&#95;1 and niacin intake among females was higher than among males(P&lt;0.01). Overall, the prevalence of inadequate vitamin intake increased with age. Rural residents had a higher prevalence of inadequate intake of vitamin C, vitamin B&#95;2 and niacin than urban residents(P&lt;0.01). Except for vitamin E, the prevalence of inadequate intake of vitamins decreased with increasing education levels. The prevalence of inadequate intake of these five vitamins was higher among participants with lower income levels than those with middle or high income(P&lt;0.01). Participants with normal weight had a higher prevalence of inadequate intake of vitamin E than those with overweight or obesity and had a higher prevalence of inadequate intake of vitamin C than those with obesity. However, participants with normal weight had a higher prevalence of inadequate intake of vitamin E than those with overweight or obesity, with the differences being statistically significant(P&lt;0.01). Except for vitamin E, the prevalence of inadequate intake of vitamins decreased with increasing physical activity intensity., Conclusion: In 2015, the usual intake of dietary vitamins of Chinese adults was low. There are differences in usual intakes of vitamins and prevalence of inadequate vitamin intake for adults aged 18 years and above in males and females, different age groups, urban and rural areas, education levels, household income levels, body mass index and physical activity intensity.

Objective: To investigate the association of urinary cadmium level with body mass index (BMI) and body circumferences among the older adults over 65 years old in 9 longevity areas of China. Methods: Subjects were older adults over 65 years old from the Healthy Aging and Biomarkers Cohort Study (HABCS) between 2017 and 2018 conducted in 9 longevity areas in China. A total of 1 968 older adults were included in this study. Information including socio-demographic characteristics, lifestyles, diet intake, and health status was collected by using questionnaires and physical examinations. Urine samples were collected to detect urinary cadmium and creatinine levels. Body circumferences included waist circumference, hip circumference and calf circumference. Subjects were divided into three groups (low:<0.77 μg/g·creatinine, middle:0.77-1.69 μg/g·creatinine, high:≥1.69 μg/g·creatinine) by tertiles of creatinine-adjusted urinary cadmium concentration. Multiple linear regression models were used to analyze the association of creatinine-adjusted urinary cadmium level with BMI and body circumferences. The dose-response relationship of creatinine-adjusted urinary cadmium concentration with BMI and body circumferences was analyzed by using restrictive cubic splines fitting multiple linear regression model. Results: The mean age of subjects was (83.34±11.14) years old. The median (Q 1 , Q 3 ) concentration of creatinine-adjusted urinary cadmium was 1.13 (0.63, 2.09) μg/g·creatinine, and the BMI was (22.70±3.82) kg/m 2 . The mean values of waist circumference, hip circumference, and calf circumference were (85.42±10.68) cm, (92.67±8.90) cm, and (31.08±4.76) cm, respectively. After controlling confounding factors, the results of the multiple linear regression model showed that for each increment of 1 μg/g·creatinine in creatinine-adjusted urinary cadmium, the change of BMI, waist circumference, hip circumference, and calf circumference in the high-level group was -0.28 (-0.37, -0.19) kg/m 2 , -0.74 (-0.96, -0.52) cm, -0.78 (-0.96, -0.61) cm, and -0.20 (-0.30, -0.11) cm, respectively. The restrictive cubic splines curve showed a negative nonlinear association of creatinine-adjusted urinary cadmium with BMI ( P nonlinear <0.001) and negative linear associations of creatinine-adjusted urinary cadmium with waist circumference ( P linear <0.001), hip circumference ( P linear <0.001), and calf circumference ( P linear <0.001). Conclusion: Urinary cadmium level is significantly associated with decreased BMI, waist circumference, hip circumference and calf circumference among older adults over 65 years old in 9 longevity areas of China.

Antibiotics are mainly used for disease treatment and prevention, and β-receptor agonists are mainly used in the clinical treatment of respiratory diseases. Both types of drugs are also widely used in animal husbandry and aquaculture to promote animal growth and prevent disease. These drugs enter the human body through many routes and cause harm to human health. Teenagers are in a critical period of growth and development, and long-term antibiotic exposure may have adverse effects on their bodies. In this study, 442 teenagers aged 11-15 years were recruited from a middle school to investigate the body burden of various antibiotics and β-receptor agonists. The seven categories of antibiotics, including five macrolides, four tetracyclines, 10 quinolones, 11 sulfonamides, three β-lactams, one quinoxaline, and one lincosamide, and four β-receptor agonists were determined by isotope dilution and solid phase extraction coupled with ultra performance liquid chromatography-tandem mass spectrometry. Analyte levels were corrected using urine creatinine, and detection rates were used for data analysis. Pearson's chi-squared test was used to analyze the correlations between detection rate and gender, age, or body mass index (BMI). Logistic regression was used to evaluate the correlation between detection rate and different groups after adjusting for confounding factors. The results showed that 397 teenagers had at least one antibiotic or β-receptor agonist in their urine, with a total detection rate of 89.8%. A total of 29 antibiotics and β-receptor agonists were detected, and the detection rate of each compound ranged from 0.2% to 59.0%. Doxycycline, oxytetracycline, and azithromycin were the top three drugs with the highest detection rates (59.0%, 56.1%, and 34.6%, respectively). Tetracyclines and macrolides were the two antibiotic categories detected most often, with detection rates of 81.9% and 42.3%, respectively. Among the antibiotics investigated, preferred veterinary antibiotics (PVAs) had the highest detection rate (85.1%), followed by human antibiotics (HAs) (41.0%). The overall detection rate of β-receptor agonists was 2.7%. Statistical analysis showed that the male was prone to be exposed to tetracycline antibiotics (odds ratio (OR)=2.17). The detection rates of macrolides differed among the different age groups and were higher in those aged 12-13 years than in those aged 11 years. As the BMI of the teenagers increased, the detection rate of macrolides gradually increased. After adjusting for age and gender, teenagers with obesity were found to be 2.35 times more likely to be exposed to macrolides than those with a normal weight. The findings suggest that teenagers are generally exposed to low levels of antibiotics, that food and the environment may be the main sources of antibiotic exposure in teenagers, and that macrolide exposure may be associated with adolescent obesity.

Objective: To explore the impact of sleep duration, physical exercise, and their interactions on the risk of dyslipidemia in older adults aged ≥80 (the oldest old) in China. Methods: The study subjects were the oldest old from four rounds of Healthy Aging and Biomarkers Cohort Study (2008-2009, 2011-2012, 2014 and 2017-2018). The information about their demographic characteristics, lifestyles, physical examination results and others were collected, and fasting venous blood samples were collected from them for blood lipid testing. Competing risk model was used to analyze the causal associations of sleep duration and physical exercise with the risk for dyslipidemia. Restricted cubic spline (RCS) function was used to explore the dose-response relationship between sleep duration and the risk for dyslipidemia. Additive and multiplicative interaction model were used to explore the interaction of sleep duration and physical exercise on the risk for dyslipidemia. Results: The average age of 1 809 subjects was (93.1±7.7) years, 65.1% of them were women. The average sleep duration of the subjects was (8.0±2.5) hours/day, 28.1% of them had sleep duration for less than 7 hours/day, and 27.2% had sleep for duration more than 9 hours/day at baseline survey. During the 9-year cumulative follow-up of 6 150.6 person years (follow-up of average 3.4 years for one person), there were 304 new cases of dyslipidemia, with an incidence density of 4 942.6/100 000 person years. The results of competitive risk model analysis showed that compared with those who slept for 7-9 hours/day, the risk for dyslipidemia in oldest old with sleep duration >9 hours/day increased by 22% ( HR =1.22, 95% CI : 1.07-1.39). Compared with the oldest old having no physical exercise, the risk for dyslipidemia in the oldest old having physical exercise decreased by 33% ( HR =0.67, 95% CI : 0.57-0.78). The RCS function showed a linear positive dose-response relationship between sleep duration and the risk for hyperlipidemia. The interaction analysis showed that physical exercise and sleep duration had an antagonistic effect on the risk for hyperlipidemia. Conclusion: Physical exercise could reduce the adverse effects of prolonged sleep on blood lipids in the oldest old.

Objective: To investigate the impact of lifestyle, apolipoprotein E (ApoE) gene, and their interaction on the risk for cognitive frailty in the elderly population in China. Methods: The study participants were from the Chinese Longitudinal Healthy Longevity Survey. The information about their lifestyles were collected by questionnaire survey, and a weighted lifestyle score was constructed based on β coefficients associated with specific lifestyles to assess the combined lifestyle. ApoE genotypes were assessed by rs429358 and rs7412 single nucleotide polymorphisms. Cognitive frailty was assessed based on cognitive function and physical frailty. Cox proportional hazards regression model was used to analyze the association of lifestyle and ApoE gene with the risk for cognitive frailty and evaluate the multiplicative and additive interactions between lifestyle and ApoE gene. Results: A total of 5 676 elderly persons, with median age [ M ( Q 1 , Q 3 )] of 76 (68, 85) years, were included, in whom 615 had cognitive frailty. The analysis by Cox proportional hazards regression model indicated that moderate and high levels of dietary diversity could reduce the risk for cognitive frailty by 18% [hazard ratio ( HR )=0.82, 95% CI : 0.68-1.00] and 28% ( HR =0.72, 95% CI : 0.57-0.91), respectively; moderate and high levels of physical activity could reduce the risk by 31% ( HR =0.69, 95% CI : 0.56-0.85) and 23% ( HR =0.77, 95% CI : 0.64-0.93), respectively. Healthy lifestyle was associated with a 40% reduced risk for cognitive frailty ( HR =0.60, 95% CI : 0.46-0.78). ApoE ε4 allele was associated with a 26% increased risk for cognitive frailty ( HR= 1.26, 95% CI : 1.02-1.56). No multiplicative or additive interactions were found between lifestyle and ApoE gene. Conclusions: Dietary diversity and regular physical activity have protective effects against cognitive frailty in elderly population. Healthy lifestyle can reduce the risk for cognitive frailty in elderly population regardless of ApoE ε4 allele carriage status.

The pollution and health effects of indoor inhalable particulate matter (PM 10 ) and fine particulate matter (PM 2.5 ) are increasingly receiving public attention. The"Standards for indoor air quality (GB/T 18883-2022)"has revised the standard limit for PM 10 and added the standard limit for PM 2.5 . This study analyzed and interpreted the relevant technical contents of the revision of the standard limits for two indicators, including the exposure status, health effects, and the basis for the determination of the limit value. It also proposed prospects for the future development and revision of standard limits for indoor particulate matters.

Formaldehyde, as an important pollutant in indoor air, has always been of great concern. In the newly issued "Standards for indoor air quality (GB/T 18883-2022)", the standard limit of formaldehyde has been restricted to 0.08 mg/m 3 . In order to better promote the implementation and application of this new standard, this study reviewed and interpreted the relevant technical content for determining the standard limit, including the indoor concentration and human exposure levels of formaldehyde, the health effects of formaldehyde, and the derivation of safety reference values. It also proposed prospect for the future development and revision of quality standards for formaldehyde in indoor air.

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. The standards for indoor air quality (GB/T 18883-2022) were issued by the State Administration of Market Regulation and the Standardization Administration on July 11, 2022, and implemented on February 1, 2023 by replacing indoor air quality standards (GB/T 18883-2002). The revised standard specifies hygienic requirements for physical, chemical, biological and radioactive indicators in indoor air and the corresponding test methods. This article interpreted the revision background, drafting principles, main indicators and methods, as well as the revision basis of the standards. Recommendations for the implementation of the standards are also proposed.

The total bacteria count has been attracting attention as an important pollutant in indoor air, and its standard limit was tightened to 1500 CFU/m 3 in "Standards for indoor air quality (GB/T 18883-2022) " .The technical contents related to the determination of the indoor air standard limits for total bacteria count were analyzed and studied, including the environmental existence level, exposure status, the health effects and the derivation of the limit value. It also proposed prospects for the future development and revision of quality standards for total bacteria count in indoor air.

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

There are clear indoor air pollution sources of trichloroethylene and tetrachloroethylene. A large number of epidemiological evidence has confirmed their carcinogenic toxicity and non-carcinogenic toxicity. Several countries and international organizations have paid attention to indoor air trichloroethylene and tetrachloroethylene. It has been also assessed that there should be certain potential health risk of indoor air trichloroethylene and tetrachloroethylene in China. Based on the latest research results of health risk assessment of indoor air trichloroethylene and tetrachloroethylene, the "Standards for indoor air quality (GB/T 18883-2022)" added trichloroethylene and tetrachloroethylene as indicators. The index limit of trichloroethylene is 6 μg/m 3 for an 8-hour average concentration. The index limit of tetrachloroethylene is 120 μg/m 3 for an 8-hour average concentration. The technical contents related to the determination of the standard limits of trichloroethylene and tetrachloroethylene in indoor air were analyzed and discussed, including the sources, the exposure, the health effects, the determination of the limit values, and the recommendations for standard implementation. It also proposed recommendations for the implementation of"Standards for indoor air quality (GB/T 18883-2022)".

Public exposure to radon has attracted increasing public concern. The newly issued "Standards for indoor air quality (GB/T 18883-2022)" has revised the radiological parameters of radon. This study analyzed and discussed the relevant technical contents about the derivation of radon limit, including the distribution level for indoor radon, exposure pathway, health effects, and the process for establishing the standard limits. Specific implementation and evaluation suggestions are also proposed.

Objective: To analyze the short-term effect of individual atmospheric PM 2.5 exposure on the diversity, enterotype, and community structure of gut microbiome in healthy elderly people in Jinan, Shandong province. Methods: The present panel study recruited 76 healthy elderly people aged 60-69 years old in Dianliu Street, Lixia District, Jinan, Shandong Province, and followed them up five times from September 2018 to January 2019. The relevant information was collected by questionnaire, physical examination, precise monitoring of individual PM 2.5 exposure, fecal sample collection and gut microbiome 16S rDNA sequencing. The Dirichlet multinomial mixtures (DMM) model was used to analyze the enterotype. Linear mixed effect model and generalized linear mixed effect model were used to analyze the effect of PM 2.5 exposure on gut microbiome α diversity indices (Shannon, Simpson, Chao1, and ACE indices), enterotype and abundance of core species. Results: Each of the 76 subjects participated in at least two follow-up visits, resulting in a total of 352 person-visits. The age of 76 subjects was (65.0±2.8) years old with BMI (25.0±2.4) kg/m 2 . There were 38 males accounting for 50% of the subjects. People with an educational level of primary school or below accounted for 10.5% of the 76 subjects, and those with secondary school and junior college or above accounting for 71.1% and 18.4%. The individual PM 2.5 exposure concentration of 76 subjects during the study period was (58.7±53.7) μg/m 3 . DMM model showed that the subjects could be divided into four enterotypes, which were mainly driven by Bacteroides, Faecalibacterium, Lachnospiraceae, Prevotellaceae, and Ruminococcaceae . Linear mixed effects model showed that different lag periods of PM 2.5 exposure were significantly associated with a lower gut α diversity index (FDR < 0.05 after correction). Further analysis showed that PM 2.5 exposure was significantly associated with changes in the abundances of Firmicutes ( Megamonas, Blautia , Streptococcus , etc.) and Bacteroidetes ( Alistipes ) (FDR<0.05 after correction). Conclusion: Short-term PM 2.5 exposure is significantly associated with a decrease in gut microbiome diversity and changes in the abundance of several species of Firmicutes and Bacteroidetes in the elderly. It is necessary to further explore the underlying mechanisms between PM 2.5 exposure and the gut microbiome, so as to provide a scientific basis for promoting the intestinal health of the elderly.

Objective: To investigate body mass index (BMI) level, identify the main type of nutritional problem, and describe the population distribution characteristics of BMI among Chinese people aged 80 years or above. Methods: The data of 9 481 oldest-old individuals were obtained from the 2017-2018 Chinese Longitudinal Healthy Longevity Survey. The Lambda-Mu-Sigma method, weighted estimates of BMI, and comparisons by BMI quintiles were used to describe the BMI level and distribution characteristics among the oldest-old. Results: The average age of the participants was (91.9±7.7) years, with P 50 of the weighted BMI at 21.9 (95% CI : 21.8-22.0) kg/m 2 The overall BMI level was low among the Chinese oldest-old and it showed a downward trend with age. Currently, the main nutritional problem among the Chinese oldest-old was undernutrition rather than overweight or obesity. Management of healthy lifestyles, functional status, and diseases would be helpful to reduce the risk of undernutrition among the oldest-old.Conclusions: The overall BMI level was low among the Chinese oldest-old and it showed a downward trend with age. Currently, the main nutritional problem among the Chinese oldest-old was undernutrition rather than overweight or obesity. Management of healthy lifestyles, functional status, and diseases would be helpful to reduce the risk of undernutrition among the oldest-old.

Disinfection of drinking water is critical to prevent waterborne diseases. An unexpected consequence of water disinfection is the formation of disinfection by-products by the interaction of disinfectants with organic matter (natural or anthropogenic) and halides, which present significant toxicological effects and carcinogenic risks. As an emerging disinfection by-product, halobenzoquinones (HBQs) have attracted increasing attention owing to their severe toxicity and high detection rates. The credible determination of HBQs is essential for further studies on their occurrence, toxicity, and control measures; however, HBQs are usually detected in drinking water at trace levels. Therefore, accurate and efficient analytical techniques are critical for HBQ determination and quantitation. In this study, a method based on solid phase extraction (SPE) combined with ultra performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS) was developed to determine 13 HBQs, including six chlorobenzoquinones, six bromobenzoquinones, and one iodobenzoquinone, in drinking water. One-liter water samples were added with 2.5 mL of formic acid, and 500 mL of each sample was collected for further enrichment. Pretreatment optimization mainly focused on the SPE column, washing solvent, and nitrogen blowing temperature. After extraction using Plexa SPE columns (200 mg/6 mL), the samples were washed with ultrapure water containing 0.25% formic acid combined with 30% methanol aqueous solution containing 0.25% formic acid, eluted with 6 mL of methanol containing 0.25% formic acid, and then nitrogen blown at 30 ℃. The UPLC-MS/MS parameters were optimized by comparing the results of two reversed-phase columns (BEH C 18 and HSS T 3 ) and various concentrations of formic acid in the mobile phase, as well as by establishing the best instrumental conditions. The separation of 13 HBQs was performed using an HSS T 3 column (100 mm×2.1 mm, 1.8 μm) via gradient elution with a mixture of 0.1% formic acid aqueous solution and methanol as the mobile phase for 16 min. The 13 HBQs were detected using a triple quadrupole mass spectrometer equipped with a negative electrospray ionization source (ESI - ) in multiple reaction monitoring (MRM) mode. Matrix-matched calibration curves were used to quantify the HBQs owing to intense matrix inhibitory effects. The results reflected the good linear relationships of the 13 HBQs and yielded correlation coefficients ( r ) greater than 0.999. The method detection limits (MDLs, S/N =3) were 0.2-10.0 ng/L, while the method quantification limits (MQLs, S/N =10) were 0.6-33.0 ng/L. The recoveries of the 13 HBQs were 56%-88% at three spiked levels (10, 20, 50 ng/L), and the relative standard deviations (RSDs, n =6) were less than or equal to 9.2%. The optimization method was applied to analyze HBQs in five drinking water samples. Four HBQs, namely, 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), and 2,6-dibromo-3,5-dimethyl-1,4-benzoquinone (2,6-DBDMBQ), were detected in the samples with detection rates of 100%, 20%, 80%, and 20%, respectively. The most frequently detected HBQ, 2,6-DCBQ, also exhibited the highest content (15.0-56.2 ng/L). The method showed high sensitivity, stability, accuracy, and efficiency, rendering it suitable for the analysis of 13 HBQs in drinking water. Compared with previous methods that mainly focused on 2,6-DCBQ and 2,6-DBBQ, the developed method achieved higher throughput and enabled the simultaneous analysis of 13 HBQs. The method presented in this study provides an opportunity to explore different types and concentrations of HBQs in drinking water, offers a deeper understanding of the occurrence of HBQs, and facilitates further studies on the health risks and control measures of these compounds.

The radioactive safety of drinking water has attracted increasing public concern. The newly issued Standards for Drinking Water Quality (GB5749-2022) in China has revised the radiological parameters. This article provides an overview of the main sources, levels of radionuclides in drinking water, and summarized the individual doses criterion and adverse health effects associated with exposure of the public to radionuclides from drinking-water. It analyzes and discusses the relevant revision content of radiological parameters, including the guidance values for screening gross α and gross β, subtracting the contribution of potassium-40 from gross β activity when the gross β activity concentration exceeds the screening level, and the basis for establishing the limit values of reference indices uranium and radium-226. Specific implementation and evaluation suggestions are also proposed.

Perchlorate is an environmental pollutant that has been a focus of attention in recent years. It has been detected in many environmental water bodies and drinking water in China, with a high level of presence in some areas of the Yangtze River Basin. The human body may ingest perchlorate through exposure pathways such as drinking water and food, and its main health effect is to affect the thyroid's absorption of iodine. The "Standards for Drinking Water Quality" (GB5749-2022) includes perchlorate as an expanded indicator of water quality, with a limit value of 0.07 mg/L. This article analyzes the technical content related to the determination of hygiene standard limits for perchlorate in drinking water, including the environmental presence level and exposure status of perchlorate, main health effects, derivation of safety reference values, and determination of hygiene standard limits.

The Drinking Water Sanitation Standard (GB 5749-2022) has been officially promulgated and implemented, with the iodide listed as a new reference indicator for water quality. This study interprets the distribution of iodine in environmental media, the impact of water iodine on health, the significance of establishing iodide standard limits, and the use of iodide standard limits, in order to provide a scientific basis for the application of iodide standard limits in this revised standard.

China is rich in antimony, boron, and vanadium mineral resources, which have been detected in environmental water bodies and drinking water. During the revision process of the "Standards for Drinking Water Quality (GB5749-2006)", research and evaluation are focused on three indicators: antimony, boron and vanadium. Vanadium is added and the limit value of boron is adjusted. This study reviews and discusses the technical contents related to the revision of the antimony, boron and vanadium, including the environmental presence levels, exposure status, health effects, and the revision of the standard limits of these three indicators. Suggestions are also made for the implementation of this standard.

The establishment of limit values for standards of drinking water quality is an important and complex process. This study systematically introduced the methodology of the establishment of standard limit values for drinking water quality and elaborated on the workflow of setting limit values of water quality indicators, principles and methods of selecting water quality indicators, derivation of safety reference values, and establishment of limit values. It also aimed to provide reference and support for the future revision of relevant standards.

Perfluorinated compounds, especially Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), are widely detected in water environments in China. Considering the potential health risks of drinking water exposure routes, PFOA and PFOS have been added to the water quality reference index of the newly issued "Standards for Drinking Water Quality (GB5749-2022)", with limit values of 40 and 80 ng/L, respectively. This study analyzed and discussed the relevant technical contents for determining the limits of the hygiene standard, including the environmental existence level and exposure status of PFOA and PFOS, health effects, derivation of safety reference values, and determination of hygiene standard limits. It also proposed prospects for the future direction of formulating drinking water standards.

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased ( OR =0.921, 95% CI : 0.889-0.954). Compared with the lowest quartile( Q 1 ) of blood selenium, the OR s (95% CI ) of Q 3 and Q Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.4 blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment ( P nonlinear >0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.

The revision of the national standards for drinking water quality is an important, rigorous and delicate endeavor. The paper introduced the revision of this standard, emphasizing the revision principle, overall technical considerations, and revision contents. Recommendations were also proposed for the implementation of this standard.

The usage of vinyl chloride and trichloroethylene in China has been increasing year by year, and they have been detected in both drinking water and environmental water, making them important environmental pollutants. Based on the latest research results on the health effects of vinyl chloride and trichloroethylene, the newly issued, "Standards for Drinking Water Quality (GB5749-2022)" in China has adjusted the standard limit of vinyl chloride from 0.005 mg/L to 0.001 mg/L and the standard limit of trichloroethylene from 0.07 mg/L to 0.02 mg/L. This article analyzed and discussed the relevant technical contents for determining the above standard limits, including the levels and exposure conditions of vinyl chloride and trichloroethylene in the water environment, health effects, derivation of safety reference values, and determination of hygiene standard limits. Suggestions were also made for the implementation of this standard.

Objective: To establish ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of 22 phospholipids in serum. Methods: In September 2022, Using synthetic non endogenous phospholipids as internal standard, phospholipids in serum were extracted by methanol-dichloromethane (2∶1, V/V ) protein precipitation method. Chromatographic separation was achieved on an ACQUITY UPLC BEH shield RP18 column, and the mobile phase was methanol/water (5∶95, V/V ) containing 10 mM ammonium formate and methanol. Detection was performed in multiple reaction monitoring mode with ion mode switching. And the method was applied by analyzing phospholipids in the serum of coal workers' pneumoconiosis patients. Results: The 22 phospholipids showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.990. The spiked recoveries of the 22 phospholipids were 81.03%-121.63% at the three spiked levels. The intra-assay were less than 14.52%, and the inter-assay were less than 15.00%. Conclusion: The method with the advantages of simplicity, stability and high sensitivity, and it can be used for the analysis of phospholipids in serum.

An analytical method combining high-throughput automatic solid-phase extraction with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to determine 16 antibiotics (macrolides, tetracyclines, quinolones, and sulfonamides) and 4 β -agonists (terbutaline, salbutamol, ractopamine, and clenbuterol) in human urine samples. After thawing at room temperature, 1 mL of urine was sampled and the internal standard was added, followed by the addition of 200 μL ammonium acetate buffer and 20 μL β -glucuronidase, and the mixture was incubated at 37 ℃ overnight. Automatic solid-phase extraction was used to extract the target compounds from the urine samples, and the recoveries were compared using different solid-phase extraction 96-well plates (PRiME MCX, Sep-Pak C 18 , PRiME HLB), types and volumes of rinse solutions and eluents. Satisfactory recoveries of the 20 target compounds were obtained using the Oasis PRiME HLB 96-well plate, with 1.5 mL 10% (v/v) methanol aqueous solution and 2.0 mL methanol as the rinse solution and eluent, respectively. The eluent was concentrated under nitrogen gas at 45 ℃, and the recoveries of the target compounds were compared under different conditions (completely or almost dry, drying to 1 mL, and adding water as a protective agent), and the recovery rate was optimal when water was added as a protective agent. In this study, two types of analytical columns (ACQUITY BEH C 18 and ACQUITY HSS T 3 ) and different gradient elution procedures and mobile phases were compared. The optimal chromatographic effect was realized using an HSS T 3 column (100 mm×3.0 mm, 1.8 μm) and 0.1% (v/v) formic acid aqueous solution-0.1% (v/v) formic acid in acetonitrile as the mobile phase in gradient elution at a flow rate of 0.3 mL/min. Comparing the peaks observed using different proportions of methanol aqueous solution and the initial mobile phase as the injection solvent revealed that 30% (v/v) methanol aqueous solution was the optimal solution in terms of peak shape and signal-to-noise ratio. MS was conducted using positive electrospray ionization (ESI + ) in multiple reaction monitoring (MRM) mode, and the MS parameters were optimized, including the curtain (CUR) and collision gases (CAD). The standard curve obtained using this method exhibited a good linearity (correlation coefficient>0.997), and the respective limits of detection and quantification were 0.02-0.12 ng/mL and 0.06-0.41 ng/mL. At spiked levels of 0.25, 2.5, and 12.5 ng/mL, the recoveries were in the range of 81.7%-120.0% (except that of tetracycline), the intra- and inter-day RSDs ( n =6) were 1.1%-11.0% and 1.2%-13.0%, respectively. Azithromycin, trimethoprim, terbutaline, salbutamol, ractopamine, and clenbuterol displayed moderate matrix effects, but all targets exhibited weak matrix effects after correction using the isotope internal standard. To evaluate the accuracy of this method, BCR-503 (containing salbutamol and clenbuterol) and internal quality control samples were used and the concentrations of salbutamol and clenbuterol were within the reference ranges. Additionally, the mean concentrations of the 20 target compounds of two different internal quality control samples after 7 measurements were in the ranges of 0.44-0.59 ng/mL (0.5 ng/mL) and 1.72-2.16 ng/mL (2.0 ng/mL), respectively, which were satisfactory. In this study, the analytical method employed automatic sample pretreatment with a 96-well solid-phase extraction plate, and the detection efficiency was considerably improved. This method displays the advantages of simple operation, ideal recovery, a high sensitivity and weak matrix effect, which satisfies the requirements for the simultaneous determination of 16 antibiotics and 4 β -agonists in human urine samples. This study provides a crucial method for use in monitoring antibiotics and β -agonists in human urine and studying their exposure characteristics and health risks.

Objective: To investigate the association of plasma vitamin B 12 level with plasma uric acid level among the elderly over 65 in 9 longevity areas of China. Methods: The elderly over 65 years old with complete information on plasma vitamin B 12 and plasma uric acid from Healthy Aging and Biomarkers Cohort Study (2017 to 2018) were recruited in this study. Information on socio-demographic characteristics, life styles, diet intake, and health status were collected by questionnaire and physical examination; and fasting venous blood was collected to detect the levels of plasma vitamin B 12 , uric acid and other indicators. Multiple linear regression models were used to analyze the association of plasma vitamin B 12 level per interquartile range increase with plasma uric acid level. The association trend of plasma vitamin B 12 level with plasma uric acid level was described by restrictive cubic splines fitting multiple linear regression model. Multiple logistic regression models were used to analyze the association of plasma vitamin B 12 level stratified by quartiles with hyperuricemia. Results: A total of 2 471 participants were finally included in the study, the age was (84.88±19.76) years old, of which 1 291 (52.25%) were female. The M ( Q 1 , Q 3 ) level of plasma vitamin B 12 was 294 (203, 440) pg/ml and the plasma uric acid level was (341.01±90.46) μmol/L. A total of 422 participants (17.08%) were defined with hyperuricemia. The results of multiple linear regression model showed that there was a positive association of plasma vitamin B 12 level with plasma uric acid level after adjustment for covariates ( P <0.05). An IQR increase in plasma vitamin B 12 (237 pg/ml) was associated with a 6.36 (95% CI : 2.00-10.72) μmol/L increase in the plasma uric acid level. The restrictive cubic splines curve showed a positive linear association of log-transformed plasma vitamin B 12 with uric acid level ( P <0.001). Conclusion: There is a positive association of plasma vitamin B 12 level with plasma uric acid level among the elderly over 65 years old in 9 longevity areas of China.

Objective: To investigate the toxicity of tris (2-chloropropyl) phosphate (TCIPP) and tributyl phosphate (TnBP) on the growth and development of zebrafish embryos, as well as to explore the underlying mechanisms at the transcriptional level. Methods: With zebrafish as a model, two hpf zebrafish embryos were exposed to TCIPP and TnBP (0.1, 1, 10, 100, 500, and 1 000 μmol/L) using the semi-static method, and their rates of lethality and hatchability were determined. The transcriptome changes of 120 hpf juvenile zebrafish exposed to environmentally relevant concentrations of 0.1 and 1 μmol/L were measured. Results: The 50% lethal concentrations (LC 50 ) of TCIPP and TnBP for zebrafish embryos were 155.30 and 27.62 μmol/L (96 hpf), 156.5 and 26.05 μmol/L (120 hpf), respectively. The 72 hpf hatching rates of TCIPP (100 μmol/L) and TnBP (10 μmol/L) were (23.33±7.72)% and (91.67±2.97)%, which were significantly decreased compared with the control group ( P <0.05). Transcriptome analysis showed that TnBP had more differential genes (DEGs) than TCIPP, with a dose-response relationship. These DEGs were enriched in 32 pathways in total, including those involved in oxidative stress, energy metabolism, lipid metabolism, and nuclear receptor-related pathways, using the IPA pathway analysis. Among them, three enriched pathways overlapped between TCIPP and TnBP, including TR/RXR activation and CAR/RXR activation. Additionally, DEGs were also mapped onto pathways of LXR/RXR activation and oxidative stress for TnBP exposure only. Conclusion: Both TCIPP and TnBP have growth and developmental toxicities in zebrafish embryos, with distinct biomolecular mechanisms, and TnBP has a stronger effect than TCIPP.

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urinary arsenic and urinary creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urinary arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95% CI ) of urinary arsenic, creatinine-adjusted urinary arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/g·Cr and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95% CI ) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m 2 group ( P interaction There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years.Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years.

Objective: To investigate the association of mixed exposure to greenness and nitrogen dioxide(NO 2 ) and hypertension among the older adults aged 65 years and over in China. Methods: The study subjects were from the Chinese Longitudinal Healthy Longevity Survey from 2017 to 2018. A total of 15 423 older adults aged 65 years and over meeting the criteria were finally included in the study. A questionnaire survey was used to collect information on demographic characteristics, lifestyle habits and self-reported prevalence of hypertension. Blood pressure values were obtained through physical examination. The level of normalized difference vegetation index(NDVI) was measured by the Medium-resolution Imaging Spectral Radiator(MODIS) of the National Aeronautics and Space Administration(NASA). The concentration of NO 2 was from China's surface air pollutant data set. Meteorological data was from NASA MERRA-2. The exposure to NDVI and NO 2 for each study subject was calculated based on the area within a 1 km radius around their residence. The association between mixed exposure of NDVI and NO 2 as well as their interaction and hypertension in older adults was analyzed by using the multivariate logistic regression model. The restrictive cubic spline(RCS) function was used to explore the exposure-response relationship between greenness and NO 2 and the risk of hypertension in study subjects. Results: The mean age of 15 423 older adults were (85.6±11.6). Women accounted for 56.3%(8 685/15 423) and 55.6%(8 578/15 423) lived in urban areas. The mean time of residence was (60.9±28.5) years. 59.8% of participants were with hypertension. The mean NDVI level was 0.41±0.13, and the mean NO 2 concentration was (32.18±10.36) μg/cm 3 . The results of multivariate logistic regression analysis showed that NDVI was inversely and linearly associated with the hypertension in older adults, with the OR( 95% CI ) value of 0.959(0.928-0.992). Compared with the T 1 group of NDVI, the risk of hypertension was lower in the T 3 group, with the OR (95% CI ) value of 0.852(0.769-0.944), and the trend test was statistically significant( P <0.05). Compared with the T 1 group of NO 2 , the risk of hypertension was higher in the T 2 and T 3 groups, with OR (95% CI ) values of 1.160(1.055-1.275) and 1.244(1.111-1.393), and the trend test was statistically significant ( P <0.05). The result of the RCS showed that NDVI was inversely and linearly associated with hypertension in older adults. NO 2 was nonlinearly associated with hypertension in older adults. The interaction analysis showed that NDVI and NO 2 had a negative multiplicative interaction on the risk of hypertension, with OR (95% CI ) value of 0.995(0.992-0.997). Conclusion: Exposure to greenness and NO 2 are associated with hypertension in older adults.

Objective: To investigate the association of the levels of high sensitivity C-reactive protein (hs-CRP) with frailty and its components among the elderly over 65 years old in 9 longevity areas of China. Methods: Cross-sectional data from the Health Ageing and Biomarkers Cohort Study (HABCS, 2017-2018) were used and the elderly over 65 years old were included in this study. Through questionnaire interview and physical examination, the information including demographic characteristics, behavior, diet, daily activity, cognitive function, and health status was collected. The association between hs-CRP and frailty and its components in the participants was analyzed by multivariate logistic regression model and restrictive cubic spline. Results: A total of 2 453 participants were finally included, the age was (84.8±19.8) years old. The median hs-CRP level was 1.13 mg/L and the prevalence of frailty was 24.4%. Compared with the low-level group (hs-CRP<1.0 mg/L), the OR (95% CI ) value of the high-level group (hs-CRP>3.0 mg/L) was 1.79 (1.35-2.36) mg/L. As for the components, the hs-CRP level was also positively associated with ADL disability, IADL disability, functional limitation and multimorbidity. After adjusting for confounding factors, compared with the low-level group, the OR (95% CI ) values of the high-level group for the four components were 1.68 (1.25-2.27), 1.88 (1.42-2.50), 1.68 (1.31-2.14) and 1.39 (1.12-1.72), respectively. Conclusion: There is a positive association between the levels of hs-CRP and the risk of frailty among the elderly over 65 years old in 9 longevity areas of China. The higher hs-CRP level may increase the risk of frailty by elevating the risk of four physical functional disabilities, namely ADL disability, IADL disability, functional limitation and multimorbidity.

Monoaromatic hydrocarbons (MAHs) such as benzene, toluene, and xylene are important anthropogenic pollutants in the urban atmosphere. The detection of urinary MAH metabolites are included in human biomonitoring programs in several countries, including Canada, the United States, Italy, and Germany, because their evaluation is vital to monitor the exposure of humans to MAHs. To this end, herein, a method was developed for the determination of seven MAH metabolites through ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). An aliquot of 0.5 mL urine was fortified with an isotopic labeled internal standard solution before being hydrolyzed by 40 μL of 6 mol/L HCl solution, followed by extraction using a 96-well EVOLUTE ® EXPRESS ABN solid-phase extraction plate. The samples were washed with 1.0 mL of methanol-water (10∶90, v/v) and eluted with 1.0 mL methanol. The eluate was diluted four times with water prior to use in instrumental analysis. Chromatographic separation was achieved using an ACQUITY UPLC HSS T3 column (100 mm×2.1 mm, 1.8 μm), with gradient elution using 0.1% formic acid as mobile phase A and methanol as mobile phase B. The detection of seven analytes was performed using a triple-quadrupole mass spectrometer equipped with a negative electrospray ionization source in the multiple reaction monitoring mode. The linear ranges of the seven analytes varied from 0.1-20 μg/L to 2.5-500 mg/L, with correlation coefficients greater than 0.995. The method detection limits were 1.5, 0.02, 0.1, 900, 0.6, and 4 μg/L for trans , trans -muconic acid (MU), S -phenylmercapturic acid (PMA), S -benzylmercapturic acid (BMA), hippuric acid (HA), 2-methyl hippuric acid (2MHA), and 3-methyl hippuric acid (3MHA)+4-methyl hippuric acid (4MHA), respectively. The limits of quantification were 5, 0.05, 0.4, 3000, 2, and 12 μg/L for MU, PMA, BMA, HA, 2MHA, and 3MHA+4MHA, respectively. The method was verified by spiking urine samples at three different concentration levels, with recovery rates ranging from 84% to 123%. The intra- and inter-day precisions were 1.8%-8.6% and 1.9%-21.4%, respectively. The extraction efficiencies were 68%-99%, and the matrix effects ranged from -11% to -87%. The urine samples obtained from the German external quality assessment scheme (round 65) were used to assess the accuracy of this method. Both high and low concentrations of MU, PMA, HA, and methyl hippuric acid were within the tolerance range. All analytes in the urine samples were found to be stable for up to seven days at room temperature (20 ℃, absence of light), with less than 15% change in concentration. Analytes in urine samples were found to be stable for at least 42 d at 4 ℃ and -20 ℃, or for six freeze-thaw cycles and up to 72 h in an autosampler (8 ℃). The method was applied to the analysis of 16 non-smokers' and 16 smokers' urine samples. The detection rates of MU, BMA, HA, and 2MHA were 100% in both non-smokers' and smokers' urine samples. PMA was detected in 75% non-smokers' and 100% smokers' urine samples. 3MHA+4MHA was detected in 81% non-smokers' urine and in all smokers' urine samples. Statistical differences were found for MU, PMA, 2MHA, and 3MHA+4MHA between the two groups ( p <0.001). The established method has good robustness and can provide reliable results. The experiments were carried out in a high-throughput manner with large sample sizes, owing to the small sample volume, and allowed the successful detection of the seven MAH metabolites in human urine.

A rapid and sensitive method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of 12 typical personal care products (PCPs) in human urine. These PCPs included five paraben preservatives (PBs), five benzophenone UV absorbers (BPs), and two antibacterial agents. Accordingly, 1 mL of the urine sample was mixed with 500 μL of β -glucuronidase-ammonium acetate buffer solution (enzymatic activities are 500 units/mL) and 75 μL of a mixed internal standard working solution (internal standard contents are 7.5 ng), followed by enzymatic hydrolysis overnight (≥16 h) at 37 ℃ in a water bath. The 12 targeted analytes were enriched and cleaned up using an Oasis HLB solid phase extraction column. Separation was performed on an Acquity BEH C 18 column (100 mm×2.1 mm, 1.7 μm) using an acetonitrile-water system as the mobile phase, in negative electrospray ionization (ESI - ) multiple reaction monitoring (MRM) mode, for target detection and stable isotope internal standard quantification. The optimal MS conditions were established by optimizing the instrument parameters and comparing two analytical columns (Acquity BEH C 18 and Acquity UPLC HSS T 3 ) as well as different types of mobile phases (methanol or acetonitrile as the organic phase) to achieve better chromatographic separation. In order to obtain higher enzymatic and extraction efficiency, different enzymatic conditions, solid phase extraction columns, and elution conditions were investigated. The final results showed that methyl parabens (MeP), benzophenone-3 (BP-3), and triclosan (TCS) showed good linearities in the ranges of 4.00-800, 4.00-800 and 5.00-200 μg/L, respectively, the other targeted compounds showed good linearities in the ranges of 1.00-200 μg/L. The correlation coefficients were all greater than 0.999. The method detection limits (MDLs) were in the range of 0.06-1.09 μg/L, and the method quantification limits (MQLs) ranged from 0.08 to 3.63 μg/L. At three spiked levels, the average recoveries of the 12 targeted analytes ranged from 89.5% to 111.8%. The intra-day and inter-day precisions were 3.7%-8.9% and 2.0%-10.6%, respectively. The results of the matrix effect assessment showed that MeP, ethyl paraben (EtP), and benzophenone-2 (BP-2) exhibited strong matrix effects (26.7%-103.8%); propyl paraben (PrP) exhibited moderate matrix effects (79.2%-112.0%); and the other eight target analytes exhibited weak matrix effects (83.3%-113.8%). The matrix effects of the 12 targeted analytes after correction using the stable isotopic internal standard method ranged from 91.9% to 110.1%. The developed method was successfully applied to the determination of the 12 PCPs in 127 urine samples. Ten typical PCPs were detected, with the overall detection rates ranging from 1.7% to 99.7%, except for benzyl paraben (BzP) and benzophenone-8 (BP-8). The results revealed that the population in this area was widely exposed to PCPs, especially MeP, EtP and PrP; the detection rates and concentrations of these PCPs were found to be very high. Our analytical method is simple and sensitive, and it is expected to be an effective tool for biomonitoring PCPs in human urine samples as part of environmental health studies.

Objective: To establish and evaluate a method of enriching bacteriophages in natural water based on ferric trichloride-polyvinylidene fluoride (FeCl 3 -PVDF)membrane filter. Methods: Based on the principle of flocculation concentration, the method of recovering bacteriophage from water sample was established by using iron ion flocculation combined with membrane filter. The titer of phage was determined by Agar double layer method. The recovery efficiency of phage was detected by phage fluorescence staining and real-time fluorescence PCR reaction. Water samples from different sources were collected for simulation experiment to evaluate the enrichment effect. At the same time, the sewage discharged from hospitals was taken as the actual water sample, and the common clinical drug-resistant bacteria were used as the host indicator bacteria to further analyze the enrichment effect of FeCl 3 -PVDF membrane filter rapid enrichment method on the bacteriophage in natural water samples. Results: The method of enrichment of bacteriophages in natural water by iron ion concentration 50 mg/L and PVDF membrane filter was established. The recovery rate of this method for bacteriophage was 93%-100%. Under the multi-functional microscope, it was found that the bacteriophage of the enriched water sample increased significantly and the fluorescence value of the enriched water sample determined by the enzyme labeling instrument was about 13 times as high as that before enrichment. After concentration of the actual water samples from the hospital drainage, the positive rate of bacteriophage isolation in the concentrated group and the non-concentrated group was 23% and 4%, and the fluorescence value in the concentrated group was 2-24 times as high as that of the non-concentrated group. Conclusion: The method of FeCl 3 -PVDF membrane filter is a simple, efficient and rapid method for enriching bacteriophages in different water samples.

Pesticides are widely used in most agricultural areas to protect food crops but adversely affect ecosystems and human beings. Pesticides have attracted great public concern due to their toxic properties and ubiquitous occurrence in the environment. China is one of the largest users and producers of pesticides globally. However, limited data are available on pesticide exposure in humans, which warrants a method for quantification of pesticides in human samples. In the present study, we validated and developed a comprehensive and sensitive method for the quantification of two phenoxyacetic herbicides, two metabolites of organophosphorus pesticides and four metabolites of pyrethroid pesticides in human urine using 96-well plate solid phase extraction (SPE) coupled with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). For this purpose, a systematic optimization of the chromatographic separation conditions and MS/MS parameters was conducted. Six solvents were optimized for the extraction and clean-up of human urine samples. The targeted compounds in the human urine samples were well separated within 16 min in one analytical run. A 1 mL aliquot of human urine sample was mixed with 0.5 mL sodium acetate buffer (0.2 mol/L) and hydrolyzed by β -glucuronidase enzyme at 37 ℃ overnight. The eight targeted analytes were extracted and cleaned using an Oasis HLB 96-well solid phase plate and eluted with methanol. The separation of the eight target analytes was performed on a UPLC Acquity BEH C 18 column (150 mm×2.1 mm, 1.7 μm) with gradient elution using 0.1% (v/v) acetic acid in acetonitrile and 0.1% (v/v) acetic acid in water. The analytes were identified using the multiple reaction monitoring (MRM) mode under negative electrospray ionization (ESI - ) and quantified by isotope-labelled analogs. Para-nitrophenol (PNP), 3,5,6-tricholor-2-pyridinol (TCPY) and cis -dichlorovinyl-dimethylcyclopropane carboxylic acid ( cis -DCCA) exhibited good linearities ranging from 0.2 to 100 μg/L, and 3-phenoxy benzoic acid (3-PBA), 4-fluoro-3-phenoxy benzoic acid (4F-3PBA), 2,4-dicholorphenoxyacetic acid (2,4-D), trans -dichlorovinyl-dimethylcyclopropane carboxylic acid ( trans -DCCA) and 2,4,5-tricholorphenoxyacetic acid (2,4,5-T) showed linearity ranging from 0.1 to 100 μg/L with correlation coefficients all above 0.9993. Method detection limits (MDLs) and method quantification limits (MQLs) of targeted compounds were in the range of 0.02 to 0.07 μg/L and 0.08 to 0.2 μg/L, respectively. The spiked recoveries of target compounds at three levels of 0.5, 5 and 40 μg/L were 91.1% to 110.5%. The inter- and intra-day precisions of targeted analytes were 2.9% to 7.8% and 6.2% to 10%, respectively. This method was applied to the analysis of 214 human urine samples across China. The results showed that all the targeted analytes, except 2,4,5-T, were detected in human urine. The detection rates of TCPY, PNP, 3-PBA, 4F-3PBA, trans -DCCA, cis -DCCA, and 2,4-D were 98.1%, 99.1%, 94.4%, 2.80%, 99.1%, 63.1% and 94.4%, respectively. The median concentration of targeted analytes in a decreasing order were: 2.0 μg/L (TCPY), 1.8 μg/L (PNP), 0.99 μg/L ( trans -DCCA), 0.81 μg/L (3-PBA), 0.44 μg/L ( cis -DCCA), 0.35 μg/L (2,4-D) and below MDLs (4F-3PBA ). For the first time, we developed a method to extract and purify specific biomarkers of pesticides from human samples based on offline 96-well SPE. This method has the advantages of simple operation, high sensitivity, and high accuracy. Moreover, up to 96 human urine samples were analyzed in one batch. It is suitable for the determination of eight specific pesticides and their metabolites in large sample sizes.