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Hexabromocyclododecane (HBCD) is the most important flame retardant that has been used in Expanded Polystyrene foam and Extruded Polystyrene foam in the past forty years across the world. China was the major producer and user of HBCD, and the total HBCD production was about 0.3 million tons. Although HBCD was completely banned in China in 2021 because of its long-range transport, bioaccumulation and toxicity, there is still a lot of residue in the environment. Therefore, we reviewed multiple studies concerning the distribution of HBCD in diverse environmental matrices, such as in the air, dust, soil, water, sediment, and biota. Results revealed that HBCD levels in different environments in China present geographical variation and were at a high level compared with other countries. In all environmental media, relatively high HBCD concentrations have been found in industrial and urban areas. Industrialization and urbanization are two important factors that influence the concentration and distribution of HBCD in the environment. In terms of isomer, γ-HBCD was the dominant isomer in soil, water, and sediment, while in the biota α-HBCD was the predominant isomer. [ABSTRACT FROM AUTHOR]

Background: Seafood is a good source of essential fatty acids which has a presumably beneficial effect on developing embryos and fetuses, although it is also a source of contaminants. In this context, pregnant women are faced with conflicting reports on the risk and benefits of seafood consumption. This study aims to assess whether the consumption of seafood during pregnancy was associated with fetal growth in an inland city in China. Methods: This study included 10,179 women who delivered a singleton live birth in Lanzhou, China. Seafood consumption was assessed using a Food Frequency Questionnaire. Maternal data including birth outcomes and maternal complications information is extracted from the medical records. Associations between seafood consumption and fetal growth indicators were analyzed using multiple linear regression and multiple logistic regression. Results: There was a positive association between total seafood consumption and birth weight (β = 0.027, 95%CI:0.030–0.111) but no association concerning birth length or head circumference. Seafood consumption was associated with decreased risk of low birth weight (OR = 0.575, 95% CI: 0.480, 0.689). The frequency of seafood consumption during pregnancy showed a trend toward a positive association with low birth weight. Significantly reduced rates of low birth weight were found in women who consumed more than 75 g of seafood/week during pregnancy as compared to women with no or very low intakes (P for trend 0.021). A significant interaction was observed between pre-pregnancy BMI and seafood consumption on birth weight among underweight women, but not among overweight women. Gestational weight gain partially mediated the association between seafood consumption and birth weight. Conclusions: Maternal seafood consumption was associated with decreased risk of low birth weight and increased birth weight. This association was mainly driven by freshwater fish and shellfish. These results further corroborate the present dietary recommendation to the Chinese Nutrition Society for pregnant women, especially those with underweight pre-pregnancy BMI and inadequate GWG. In addition, our findings provide implications for future interventions to improve seafood consumption among pregnant women to prevent low birth weight babies in the inland city in China. [ABSTRACT FROM AUTHOR]

BACKGROUND: Human breast milk is a primary route of exposure to perfluoroalkyl substances (PFAS) in infants. To understand the associated risks, the occurrence of PFAS in human milk and the toxicokinetics of PFAS in infants need to be addressed. OBJECTIVES: We determined levels of emerging and legacy PFAS in human milk and urine samples from Chinese breastfed infants, estimated renal clearance, and predicted infant serum PFAS levels. METHODS: In total, human milk samples were collected from 1,151 lactating mothers in 21 cities in China. In addition, 80 paired infant cord blood and urine samples were obtained from two cities. Nine emerging PFAS and 13 legacy PFAS were analyzed in the samples using ultra high-performance liquid chromatography tandem mass spectrometry. Renal clearance rates (CLrenals) of PFAS were estimated in the paired samples. PFAS serum concentrations in infants (<1 year of age) were predicted using a first-order pharmacokinetic model. RESULTS: All nine emerging PFAS were detected in human milk, with the detection rates of 6:2 Cl-PFESA, PFMOAA, and PFO5DoDA all exceeding 70%. The level of 6.2 Cl-PFESA in human milk (median concentration=13.6 ng/L) ranked third after PFOA (336 ng/L) and PFOS (49.7 ng/L). The estimated daily intake (EDI) values of PFOA and PFOS exceeded the reference dose (RfD) of 20 ng/kg BW per day recommended by the U.S. Environmental Protection Agency in 78% and 17% of breastfed infant samples, respectively. 6.2 Cl-PFESA had the lowest infant CLrenal (0.009 mL/kg BW per day), corresponding to the longest estimated half-life of 49 y. The average half-lives of PFMOAA, PFO2HxA, and PFO3OA were 0.221, 0.075, and 0.304 y, respectively. The CLrenals of PFOA, PFNA, and PFDA were slower in infants than in adults. CONCLUSIONS: Our results demonstrate the widespread occurrence of emerging PFAS in human milk in China. The relatively high EDIs and half-lives of emerging PFAS suggest potential health risks of postnatal exposure in newborns. [ABSTRACT FROM AUTHOR]

BACKGROUND: Perfluoroalkyl acids (PFAA) have been measured in ovarian follicular fluid from women using in vitro fertilization (IVF), although associations between follicular fluid PFAA and IVF outcomes have been inconsistent. OBJECTIVES: We investigated the association between follicular fluid PFAA and embryo quality in women undergoing IVF. METHODS: We prospectively enrolled 729 women undergoing IVF treatment in Guangxi province, China, from July 2018 to December 2018. We measured 32 PFAA, including branched isomers, in follicular fluid using ultra-performance liquid chromatography coupled to tandem mass spectrometry. We applied restricted cubic splines, linear regression, and log-binominal regression models to investigate associations between follicular fluid PFAA and embryo quality, adjusting for confounding variables and investigated oocyte maturity as an intervening variable using causal mediation analysis. We further estimated the overall effect of the PFAA mixture on outcomes using Bayesian kernel machine regression (BKMR). RESULTS: We detected 8 of 32 measured PFAA in >85% of follicular fluid samples. Higher PFAA concentrations were associated with fewer high-quality embryos from IVF. The high-quality embryo rates at the 50th percentile of linear perfluoro-1-octanesulfonate acid (n-PFOS), all branched PFOS isomers (Br-PFOS) and linear perfluoro-n-octanoic acid (n-PFOA) were -6.34% [95% confidence interval (CI): -9.45, -3.32%], -16.78% (95% CI: -21.98, -11.58%) and -8.66% (95% CI: -11.88, -5.43%) lower, respectively, than the high quality embryo rates at the reference 10th percentile of PFAA. Oocyte maturity mediated 11.76% (95% CI: 3.18, 31.80%) and 14.28% (95% CI: 2.95, 31.27%) of the n-PFOS and n-PFOA associations, respectively. The results of the BKMR models showed a negative association between the PFAA mixture and the probability of high-quality embryos, with branched PFOS isomers having posterior inclusion probabilities of 1 and accounting for the majority of the association. DISCUSSION: Exposure to higher PFAA concentrations in follicular fluid was associated with poorer embryo quality during IVF. Branched PFOS isomers may have a stronger effect than linear PFOS isomers. More studies are needed to confirm these findings and to directly estimate the effects on pregnancy and live-birth outcomes. [ABSTRACT FROM AUTHOR]

(a) Background: Omalizumab is an anti-IgE humanized monoclonal antibody marketed in China for the conventional treatment of poorly controlled moderate-to-severe allergic asthma. Numerous clinical trials have demonstrated the effectiveness of omalizumab, but the data from studies in actual clinical treatment are still relatively limited. (b) Methods: Thirty-two patients with moderate-to-severe allergic asthma treated with omalizumab on the basis of ICS-LABA (inhaled corticosteroids/long-acting beta2-agonist) were selected. Clinical characteristics before and after treatment were collected to analyze the relationship between changes in serum total IgE levels and peripheral blood EOS (eosinophil) levels, FEV1 (forced expiratory volume in 1 second), PEF (peak expiratory flow), OCS (oral glucocorticoid) dosage, ATC (asthma control test) score, and the number of acute exacerbations and the treatment response, in order to observe the efficacy of omalizumab in addition to primary therapy, and to investigate whether baseline clinical characteristics such as serum total IgE and EOS levels could predict a treatment response. (c) Results: Using the ACT score as an evaluation, 68.75% of patients benefited from omalizumab treatment at the end of 16 weeks. The response group has a reduction in OCS dosage (p-values of 0.026 and 0.039), a significant reduction in ACT scores (both p < 0.001), and a reduction in the number of acute exacerbations (p = 0.034 and 0.025, respectively) after omalizumab treatment. The binary logistics analysis of factors affecting the effectiveness of omalizumab in the treatment of allergic asthma were total serum IgE and the presence of comorbidities (p-values of 0.039 and 0.046, respectively). (d) Conclusions: Combining omalizumab with ICS-LABA for 16 weeks significantly improves asthma symptoms in Chinese adults and can be used as an add-on treatment. In addition, high serum IgE levels and the presence of comorbidities were predictors of its therapeutic efficacy. [ABSTRACT FROM AUTHOR]

Hexabromocyclododecane (HBCD) was listed in Annex A of the Stockholm Convention on Persistent Organic Pollutants for its persistence, bioaccumulation and toxicity, and pose significant adverse effects on natural environments and human health. HBCDs are ubiquitously found in marine environments worldwide and can be biomagnified in marine organisms with a high trophic level. In the present study, we reviewed the available data on contamination of HBCDs in the marine biota from China, including mollusks, crustaceans, fish and mammals. Bioaccumulation and biomagnification of HBCDs in the marine food web were summarized as well. This study also prospected the future research of HBCDs, including the transport and fluxes of HBCDs to and within the marine environment, the biomagnification of HBCDs in different ecosystems, and the metabolism of HBCDs in different marine species. [ABSTRACT FROM AUTHOR]

As health challenging rural elderly in an aging population, more attention is being paid on impact of family intergenerational support on the health of the elderly. This paper investigates the effects of children's intergenerational economic support and non-economic support on physical, mental, and functional health of rural elderly in China in the mean while. This paper applies the 2014 Chinese Longitudinal Healthy Longevity Survey (CLHLS), in particular, applying exploratory factor analysis to ascertain latent variables and Structural Equation Model (SEM), and analyzes the impacts of "Upward" intergenerational support on health of rural elderly. As resulted, after controlling the socioeconomic status of the rural elderly, the family "upward" intergenerational support influences the elderly's physical health at a percentage of 11.7%, mental health 29.8%, and physiological function 12.6%. Moreover, "Upward" economic support has a positive effect on physiological function (P<0.05). "Upward" non-economic support has negative effects on physiological function and mental health (P<0.05), while it has a positive effect on physical health. In addition, economically independent rural elderly are more likely to benefit from the health of "upward" intergenerational support, especially mental health. In particular, those results are robust. "Upward" intergenerational support plays an important role for the health of rural elderly. For the rural elderly of economic independence, to improve the quality of care and spiritual support, it is important to solve the health problems. In addition, it is necessary to build a comprehensive old-age security and support system for family, community, and society jointly to improve the health of the rural elderly. [ABSTRACT FROM AUTHOR]

Study Question: Are maternal plasma concentrations of perfluoroalkyl and polyfluoroalkyl substances (PFASs) during pregnancy associated with anogenital distance (AGD) in male infants at birth, 6, and 12 months of age?Summary Answer: Higher maternal plasma concentrations of some PFASs were associated with shorter AGD in male infants at birth and 6 months of age.What Is Known Already: Two animal studies have found that exposure to PFASs was associated with shorter AGD in male rat fetuses and wild male minks. There is only one human study on the topic that did not identify consistent patterns between maternal serum concentrations of PFASs during pregnancy and AGD in male infants.Study Design, Size, Duration: In the prospective cohort study, a total of 1292 eligible pregnant women were recruited at 12-16 weeks of gestation between April and December 2012 at the Maternal and Child Health Hospital of Minhang district in Shanghai, China. At delivery, 667 male singletons were born. They were then followed up at birth (n = 439) and at 6 (n = 411) and 12 months (n = 376) of age when anopenile distance (AGDAP) and anoscrotal distance (AGDAS) were measured.Participants/materials, Setting, Methods: A total of 500 male infants who had both maternal plasma concentrations of PFASs and at least one AGD measurement of at three time points were included in the present study. Multiple linear regression models were used to evaluate the potential linear associations between maternal concentrations of PFASs and AGD.Main Results and the Role Of Chance: Maternal plasma concentrations (ln-transformed) of perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUdA) were inversely associated with AGDAS or AGDAP at birth (AGDAS: per ln unit increase in PFAS concentrations: β (95% CI): -0.65 (-1.27 to -0.02) mm for PFOS; -0.58 (-1.11 to -0.06) mm for PFDA; and -0.57 (-1.09 to -0.06) mm for PFUdA; AGDAP: per ln unit increase in PFAS concentrations: β (95% CI): -0.63 (-1.24 to -0.01) mm for PFDA and - 0.76 (-1.36 to -0.16) mm for PFUdA). At 6 months of age, per unit increase in maternal ln concentrations of PFOS and perfluorotridecanoic acid (PFTrDA), AGDAS decreased on average by -2.21 (95% CI: -4.28 to -0.14) and -1.11 (95% CI: -2.17 to -0.06) mm, respectively. Additionally, ln-transformed perfluorooctanoic acid (PFOA) showed nonsignificant but inverse associations with both AGDAS and AGDAP at 6 months of age. We found no significant associations between ln-transformed maternal concentrations of PFASs and either AGDAS or AGDAP at 12 months of age. However, significantly inverse association of ln-transformed PFOA with AGDAP was observed in male infants who never or shortly breastfed (<3 months) at 12 months of age.Limitations, Reasons For Caution: AGD measurements were performed by different examiners at each follow-up visit, and the intra-examiner variation was not assessed, which might cause intra-rater and inter-rater measurement errors. Additionally, our study may have selection bias since a considerable number of participants withdrew from the cohort although the differences in demographic characteristics were not statistically significant between included mother-infant pairs and those excluded. No statistical correction was made for multiple comparisons.Wider Implications Of the Findings: Our findings may have important implications for the early development of genital health in male infants since PFASs can be detected in almost all pregnant women and infants worldwide.Study Funding/competing Interest(s): This study was supported by grants from the National Key Research and Development program of China (2018YFC1002801 and 2016YFC1000505), the Science and Technology Commission of Shanghai Municipality (16ZR1430100), the National Natural Science Foundation of China (81428011), and the Innovation-Oriented Science and Technology Grant from National Health Commission Key Laboratory of Reproduction Regulation (CX2017-06). The authors have no conflicts of interest to declare.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Background: Perfluoroalkyl and polyfluoroalkyl substances (PFAS) have been reported to disrupt endocrine system and reproduction. However, epidemiological evidence on the association between PFAS and preeclampsia is inconsistent. We aimed to investigate the association between prenatal PFAS exposure and hypertensive disorders of pregnancy (HDP) in humans.Methods: PFAS were measured by liquid chromatography system coupled with tandem mass spectrometry in 687 umbilical cord plasma samples collected between 2011 and 2012 in Shanghai, China. Information on HDP including gestational hypertension and preeclampsia was abstracted from medical records. Multiple logistic regression was used to examine the association of each PFAS with gestational hypertension, preeclampsia, and overall HDP in separate models. Elastic net regression with logit link was used to identify independent associations between exposures and outcomes. Logistic regression was used to obtain the unpenalized estimates of the selected PFAS components for the associations with outcomes, adjusting for age, education level, pre-pregnancy BMI, parity, and mutual adjustment of selected PFAS.Results: The risk of gestational hypertension and preeclampsia was 3.3% and 2.8% in our subjects, respectively. Perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluoroundecanoic acid (PFUA) were associated with preeclampsia based on elastic net penalty regression. In the fully adjusted statistical model, women with a higher level of standardized ln-transformed PFBS had an increased odds of preeclampsia [adjusted odds ratio (AOR): 1.81, 95% confidence interval (CI): 1.03-3.17], and overall HDP (AOR: 1.64, 95% CI: 1.09-2.47).Conclusions: Prenatal exposure to PFBS was positively associated with the risk of preeclampsia and overall HDP. [ABSTRACT FROM AUTHOR]

BACKGROUND: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent synthetic chemicals that are widely used in industrial applications and often detectable in humans. In rats, PFASs can interfere with the estrous cycle. In humans, menstruation has been viewed as a proxy of female fecundity, and periodic menstruation plays a critical role in endometrial sloughing in the absence of pregnancy and in preparing for embryo implantation. OBJECTIVES: We investigated the association between PFAS exposure and menstrual cycle characteristics in women who plan to become pregnant. METHODS: Plasma level of 10 PFASs was measured in 950 women who were attempting to become pregnant and recruited in two preconception care clinics in Shanghai, China, from August 2013 to April 2015. Information on menstrual cycle characteristics was collected by questionnaires. Associations between PFAS levels and menstrual cycle regularity, length, and bleeding volume were examined using multiple logistic regression models. RESULTS: Pre-pregnant women with higher levels of log-transformed perfluorooctanate (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexanesulfonate (PFHxS) had increased odds of self-reported history of irregular menstrual cycle [PFOA-adjusted odds ratio (OR)=1.52 (95% CI: 1.08, 2.15); PFOS OR=1.29 (95% CI: 0.98, 1.70); PFNA OR=1.50 (95% CI: 1.03, 2.07); PFHxS OR=1.80 (95% CI: 1.17, 2.77)] and long menstrual cycle [PFOA OR=1.50 (95% CI: 1.06, 2.10); PFOS OR=1.34 (95% CI: 1.02, 1.75); PFNA OR=1.49 (95% CI: 1.05, 2.11); PFHxS OR=1.73 (95% CI: 1.13, 2.65)]. Log-transformed PFOA, PFOS, PFNA. and PFHxS levels were negatively associated with self-reported history of menorrhagia [PFOA OR=0.37 (95% CI: 0.21, 0.65); PFOS OR=0.57 (95% CI: 0.37, 0.90); PFNA OR=0.47 (95% CI: 0.26, 0.86); PFHxS OR=0.14 (95% CI: 0.06, 0.36)]. CONCLUSIONS: Certain PFASs are associated with abnormal menstruation in humans. [ABSTRACT FROM AUTHOR]

BACKGROUND: Previous studies have suggested that elevated exposure to disinfection by-products (DBPs) in drinking water during gestation may result in adverse birth outcomes. However, the findings of these studies remain inconclusive. OBJECTIVE: The purpose of our study was to examine the association between blood biomarkers of late pregnancy exposure to trihalomethanes (THMs) in drinking water and fetal growth and gestational age. METHODS: We recruited 1,184 pregnant women between 2011 and 2013 in Wuhan and Xiaogan City, Hubei, China. Maternal blood THM concentrations, including chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM), were measured as exposure biomarkers during late pregnancy. We estimated associations with gestational age and fetal growth indicators [birth weight, birth length, and small for gestational age (SGA)]. RESULTS: Total THMs (TTHMs; sum of TCM, BDCM, DBCM, and TBM) were associated with lower mean birth weight (-60.9 g; 95% CI: -116.2, -5.6 for the highest vs. lowest tertile; p for trend = 0.03), and BDCM and DBCM exposures were associated with smaller birth length (e.g., -0.20 cm; 95% CI: -0.37, -0.04 for the highest vs. lowest tertile of DBCM; p for trend = 0.02). SGA was increased in association with the second and third tertiles of TTHMs (OR = 2.91; 95% CI: 1.32, 6.42 and OR = 2.25; 95% CI: 1.01, 5.03; p for trend = 0.08). CONCLUSIONS: Our results suggested that elevated maternal THM exposure may adversely affect fetal growth. [ABSTRACT FROM AUTHOR]

A 2-year monitoring study was conducted to estimate nitrogen deposition to a typical red soil forestland in southeastern China. The dry deposition velocities ( Vd) were estimated using big leaf resistance analogy model. Atmospheric nitrogen dry deposition was estimated by combing Vd and nitrogen compounds concentrations, and the wet deposition was calculated via rainfall and nitrogen concentrations in rainwater. The total inorganic nitrogen deposition was 83.7 kg ha − 1 a − 1 in 2004 and 81.3 kg ha − 1 a − 1 in 2005, respectively. The dry deposition contributed 78.6% to total nitrogen deposition, in which ammonia was the predominant contributor that accounted for 86.1%. Reduced nitrogen compounds were the predominant contributors, accounting for 78.3% of total nitrogen deposition. The results suggested that atmospheric inorganic nitrogen could be attributed to intensive agricultural practices such as excessive nitrogen fertilization and livestock production. Therefore, impacts of atmospheric nitrogen originated from agriculture practices on nearby forest ecosystems should be evaluated. [ABSTRACT FROM AUTHOR]

This paper presents a modification of chemical oxygen demand (COD) monitoring giving a better indication of the pollution level compared with the conventional COD method for rivers with a high content of sediments. The correlation between the sediment organic carbon and COD was investigated using sediments sampled in the middle Yellow River, China. Partitioning Of the sediment organic carbon between the water and sediment phases was also investigated using batch experiments, with the sediment concentration varying from 20 to 400 g/L. As a result, the COD modification equations are proposed for both turbid water (mixture of water and sediment) and supematant water (filtrate using a 0.45-µm membrane). The modified COD in turbid water and supematant water could be 40 and 10% less than the monitored COD values, respectively. These results may have a significant influence on the assessment of water quality class in the Yellow River. Water Environ. Res., 79, 2336 (2007). [ABSTRACT FROM AUTHOR]