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The historical annual loading to, removal from, and cumulative burden in the Arctic Ocean for β-hexachlorocyclohexane (β-HCH), an isomer comprising 5-12% of technical HCH, is investigated using a mass balance box model from 1945 to 2020. Over the 76 years, loading occurred predominantly through ocean currents and river inflow (83%) and only a small portion via atmospheric transport (16%). β-HCH started to accumulate in the Arctic Ocean in the late 1940s, reached a peak of 810 t in 1986, and decreased to 87 t in 2020, when its concentrations in the Arctic water and air were ∼30 ng m

BaLi2Ti6O14, a promising anode material for lithium-ion battery application, was successfully prepared by a sol-gel method. To improve the structural stability and electrochemical performance of the materials, an ionic conductive Al2O3 layer was introduced. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the particles become smaller and distribute more uniformly because of the coating, and possible mechanism was discussed. Our experiments further showed that BLTO-4 sample has the best electrochemical performance. Furthermore, excessive coating will lead to a decrease of reversible capacity, because Al2O3 has no electrochemical activity. The charge and discharge capacities of BLTO-4 are 174.9 and 175.9 mAh g−1 after 50 cycles at 0.2 C, which are much higher than those of the pure sample (107.3 and 108.4 mAh g−1). Even at 10 C, BLTO-4 still delivers a reversible specific capacity of 98.6 mAh g−1 after 1000 cycles. The good cyclic stability and rate performance of BLTO-4 can be attributed to the reduced particle size and the advantages of the Al2O3 coating layer, which is favorable for the enhancement of the structural stability and the reduction of the charge transfer resistance of the materials.

Numerous studies have shown that graphene oxide (GO) respiratory exposure led to severe lung injury, but whether pulmonary fibrosis caused by GO respiratory exposure is related to the activation of the caspase-1/p38MAPK/TGF-β1 remains unclear. In this study, rats were administrated GO by intratracheal instillation and fed for three months, and the molecular mechanisms of GO on the pulmonary fibrosis and other organ damage caused by GO respiratory exposure were examined. The results showed that the expression of caspase-1/p38MAPK/TGF-β1 pathway-related factors were significantly elevated with the increase of exposure concentrations of GO. Those data proved that the caspase-1/p38MAPK/TGF-β1 signaling pathway was involved in the pulmonary fibrosis caused by GO respiratory exposure. The trends of related factors also proved that the caspase-1/p38MAPK/TGF-β1 pathway was likely to play a dominant role in the sub-acute and sub-chronic stages. The other organ damage examination found that the liver and spleen were damaged initially by the GO respiratory exposure. Meanwhile for the testicle, although the acute injury was severe, signs of recovery were found during the three-month trial period.

Gas/particle (G/P) partitioning is an important behavior for the atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). In this study, paired daytime and nighttime air samples were collected for one year in order to study the diurnal and nocturnal variations of concentration and G/P partitioning of PAHs. Higher PAHs concentrations in total phase were observed in nighttime. The geomean (GM) concentrations of Σ

In this paper, two level III fugacity models are developed and applied using an environmental system containing six compartments, including air, aerosols, soil, water, suspended particulate matters (SPMs), and sediments, as a “unit world”. The first model, assumes equilibrium between air and aerosols and between water and SPMs. These assumptions lead to a four-fugacity model. The second model removes these two assumptions leading to a six-fugacity model. The two models, compared using four PBDE congeners, BDE-28, -99, −153, and −209, with a steady flux of gaseous congeners entering the air, lead to the following conclusions. 1. When the octanol-air partition coefficient (KOA) is less than 1011.4, the two models produce similar results; when KOA > 1011.4, and especially when KOA > 1012.5, the model results diverge significantly. 2. Chemicals are in an imposed equilibrium in the four-fugacity model, but in a steady state and not necessary an equilibrium in the six-fugacity model, between air and aerosols. 3. The results from the six-fugacity model indicate an internally consistent system with chemicals in steady state in all six compartments, whereas the four-fugacity model presents an internally inconsistent system where chemicals are in equilibrium but not a steady state between air and aerosols. 4. Chemicals are mass balanced in air and aerosols predicted by the six-fugacity model but not by the four-fugacity model. If the mass balance in air and aerosols is achieved in the four-fugacity model, the condition of equilibrium between air and aerosols will be no longer valid.

Gas/particle (G/P) partition quotients of semi-volatile organic compounds (SVOCs) for bulk air have been widely discussed in experimental and theoretical contexts, but research on size-resolved G/P partition quotients (KPi) are scarce and limited in scope. To investigate G/P partition behavior of polybrominated diphenyl ethers (PBDEs) for size-segregated particles in the atmosphere, 396 individual size-segregated particulate samples (36 batches × 11 size-ranges), and 108 pairs of concurrent gaseous and bulk particulate samples were collected in Harbin, China. A steady-state equation based on bulk particles is derived to determine G/P partition quotients of PBDEs for size-segregated particles, which depends on the organic matter contents of size-segregated particles (fOMi). This equation can well predict KPi with knowledge of bulk partition quotient (KPS), ambient temperature, and fOMi, the results of which match well with monitoring data in Harbin and other published data collected in Shanghai and Guangzhou of China and Thessaloniki of Greece, and remedies a defect of over-estimate KPi for high-brominated PBDEs by the previous equation. In particular, the new equation contributes to obtaining the PBDEs concentrations in all atmospheric phase from partial phase, then provides a credible path to evaluate healthy exposure dose from the airborne PBDEs, by co-utilization with exposure models.

The study on atmospheric polycyclic aromatic hydrocarbons (PAHs) in China has regional and global significance to understand the large scale atmospheric transport of PAHs. In this study, 16 US EPA priority PAHs were analyzed in more than 500 pairs of gas and particle phases samples, which were collected on the same schedule on a weekly basis from August 2008 to July 2009 at 11 urban sites (6 northern cities and 5 southern cities) across China. The average concentration was 239 ± 329 ng/m3 and 165 ± 164 ng/m3 for the northern cities and the southern cities, respectively. Different seasonal variations of atmospheric PAHs were observed between northern cities and southern cities, which were mainly caused by the different temperature effects in winter. Identified by principal component analysis, coal combustion and vehicle exhaust were the major sources of atmospheric PAHs in northern and southern cities of China, respectively. The temperature dependences of atmospheric PAHs were also different, which were caused by the different influences of temperature on identified sources. To our knowledge, this is the first comprehensive study to report the difference with concentrations, seasonal variations, sources and temperature dependences of atmospheric PAHs between northern cities and southern cities in China.

Gas-particle (G/P) partition is the determining factor to the behaviors of semi-volatile organic compounds (SVOCs) in atmosphere, such as transport and deposition. Based on a case study on the measurement of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Harbin City in China from June 2014 to May 2019, the long-term temporal trend of G/P partition of PAHs and its influencing factors were comprehensively studied. The results indicated that an obvious decreasing temporal trend was observed for total suspended particle (TSP) with the annual mean concentrations of 180, 173, 134, 132, and 119 μg/m3 for the five years. The results demonstrated the effectiveness of the Clean Air Action on decreasing TSP levels in Harbin City. For most PAHs, obvious long-term temporal trends and seasonal variations were observed for the particulate phase fraction (φP) and the G/P partitioning quotient (KP) by fitting with a simple harmonic regression method. Significant correlations between φP with temperature and TSP indicated their influences on the temporal trend of φP. Similarly, the temperature was also the direct influencing factor to the temporal trend of KP. For the five years, non-obvious differences were observed with the linear relationships between log KP vs. log KOA, and between log KP vs. log PL. The comparison between the monitoring data of φP and log KP with the prediction data from the G/P partitioning models indicated that the predictions of the models did not well match all the monitoring data for the period. Therefore, more studies should be conducted to better understand the G/P partitioning mechanism of PAHs in atmosphere and to establish more accurate G/P partitioning models. In summary, the results of the present study provided new insight into the G/P partitioning behavior of PAHs in the atmosphere, especially for the temporal trend of φP and log KP.

Benzotriazoles (BTs) UV filters are widely used as ultraviolet absorbents for our daily products, which received increasing attention in the past decades. Residential wastewater treatment plant (WWTP) is both an important sink for wastewater and a key pollution source for receiving water for these chemicals. In this study, pretreatment and gas chromatography-tandem mass spectrometry analysis method were developed to determine the occurrence and fate of 9 BTs UV filters in wastewater and sludge from the WWTP with anaerobic-oxic treatment process (A/O) and biological aerated filter treatment process (BAF). Totally, 81 wastewater samples and 11 sludge samples were collected in four seasons. In wastewater, UV-326 and UV-329 were frequently detected, while the highest mean concentrations were detected for UV-234 and UV-329. The concentrations were in the range ofLOQs up to several hundred nanograms per liter. The removal efficiency of BTs UV filters was85% in A/O process and 60-77% in BAF process except for UV-350, which was more difficult to remove with lower removal efficiencies of 33.3% for both A/O and BAF. All the target chemicals except for UV-320 were detected in sludge samples with the mean concentration ranging from 0.90 ng/g to 303.39 ng/g. There was no significant difference with concentrations and removal efficiency among different seasons. Higher detection frequency and concentration of BTs UV filters in downstream of the receiving water system indicated the contribution of effluent of the WWTP. Compared with other rivers, the lower concentrations in surface water in the Songhua River indicated light pollution status with of BTs UV filters.

Short-chain chlorinated paraffins (SCCPs) are widely used chemicals in household products and might cause adverse human health effects. However, limited information is available on the occurrence of SCCPs in indoor environments and their exposure risks on humans. In this study the concentrations, profiles and human exposure of SCCPs in indoor dust from five different indoor environments, including commercial stores, residential apartments, dormitories, offices and laboratories were characterized. The SCCPs levels ranged from 10.1 to 173.0 μg/g, with the median and mean concentration of 47.2 and 53.6 μg/g, respectively. No significant difference was found on concentrations among the five microenvironments. The most abundant compounds in indoor dust samples were homologues of C 13 group, Cl 7 group and N 20 (N is the total number of C and Cl) group. In the five microenvironments, commercial stores were more frequently exposed to shorter carbon chained and higher chlorinated homologues. Three potential sources for SCCPs were identified by the multiple linear regression of factor score model and correspondence analysis. The major sources of SCCPs in indoor dust were technical mixtures of CP–42 (42% chlorine, w/w) and CP–52 b (52% chlorine, w/w). The total daily exposure doses and hazard quotients (HQ) were calculated by the human exposure models, and they were all below the reference doses and threshold values, respectively. Monte Carlo simulation was applied to predict the human exposure risk of SCCPs. Infants and toddlers were at risk of SCCPs based on predicted HQ values, which were exceeded the threshold for neoplastic effects in the worst case. Our results on the occurrences, sources and human exposures of SCCPs will be useful to provide a better understanding of SCCPs behaviors in indoor environment in China, and to support environmental risk evaluation and regulation of SCCPs in the world.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants in atmosphere, which attracted more attentions due to their influence on human health. In this study, a national scale cancer risk (CR) assessment with atmospheric PAHs were conducted based on one year monitoring program at 11 cities across China. The annual mean concentrations of benzo[a]pyrene (BaP) and BaP equivalency (BaPeq) were 4.56 ± 7.78 ng/m3 and 8.45 ± 14.1 ng/m3, respectively, which were both higher than the new ambient air quality standards of China (GB 3095–2012, 1 ng/m3). Concentrations of BaP and BaPeq in northern Chinese cities were almost 2 times higher than those in southern Chinese cities. The CR values induced by the dermal contact exposure were two orders of magnitude higher than that by the inhalation exposure. Children and adults were the most sensitive age groups with the dermal contact exposure and the inhalation exposure to atmospheric PAHs, respectively. For the total CR values, 99.7% of its values were higher than the reference level of 10−6. No significant difference of the total CR values was observed between northern Chinese and southern Chinese cities for children and adults. In order to quantify the uncertainties of CR assessment, Monte Carlo Simulation was applied based on the specific distributions of the exposure factors cited from the Exposure Factors Handbook of Chinese Population. The results indicated that almost 90% probability of the total CR values were higher than 10−6, indicating potential cancer risk. Sensitive analysis indicated that atmospheric concentration, outdoor exposure fraction, particle amount adhered to skin, and cancer slope factor should be carefully considered in order to increase the accuracy of CR assessment with PAHs in atmosphere.

The purpose of this study was to investigate the association between refined grains intake and obesity in China. Refined grain intake was considered in relation to energy intake and at varied levels of macronutrient distribution. A cross-sectional study of 6913 participants was conducted using internet-based dietary questionnaire for Chinese (IDQC). The associations and dose–response relationships between refined grains intake and obesity were investigated using multivariable logistic regression analyses and restricted cubic spline (RCS) models. There was a positive association between refined grains intake and abdominal obesity for all participants (forth quartile OR, 1.313; 95% CI, 1.103–1.760; p

Human exposure to formaldehyde, toluene, xylene (FTX) and other volatile organic compounds (VOCs) are associated with negative health impact. To characterize the exposure and health effects of FTX and TVOC from indoor environments, we conducted an extensive monitoring campaign involving 1278 measurements of 472 indoor locations in Harbin, a megacity in China from May 2013 to March 2018. The results showed that household had the highest mean formaldehyde concentration (0.171 ± 0.084 mg m-3) among all types of indoor environments. Meanwhile, there was no significant differences in formaldehyde concentration of the living room, master bedroom, secondary bedroom and study room (p > 0.05), as well as toluene and xylene. The highest mean concentration of toluene, xylene and TVOC was measured in public bath center. Great difference was found between formaldehyde concentrations in 2013 and other years, except 2015. There were great positive nonlinear correlations between the indoor temperature and concentration of formaldehyde (p

The Songhua River is one of the most populated and oldest industrial areas in Northeast China. To understand the sources and distribution of polycyclic aromatic hydrocarbons and their derivatives, such as 16 priority (PAHs), 33 methylated (Me-PAHs), and 12 nitrated (NPAHs) in river water and sediment, were noticed. The concentrations of ∑PAHs, ∑Me-PAHs, and ∑NPAHs in river water scaled from 135 to 563, 9.36 to 711, and 1.26 to 64.7 ng L−1, with mean values of 286, 310, and 17.9 ng L−1, and those in sediments were from 35.8 to 2000 ng g−1, 0.62 to 394 ng g−1, and 0.28 to 176 ng g−1 (dry weight) with mean values of 283, 103, and 21.7 ng g−1. The compositions proved that two-ring and three-ring compounds of PAHs, NPAHs, and four-ring, six-ring of Me-PAHs were prevalent in water samples, in contrast, four-ring dominated in sediments. Principal components analysis (PCA) and diagnostic ratios confirmed that pollutant source was mixed petrogenic and pyrogenic origin. The fugacity fraction (ƒƒ) was also calculated to explain the trend of sediment–water exchange, high ƒƒ values found in summer, for most HMW PAHs and Me-PAHs that these substances acted as a secondary source of emissions from sediment to water. The risk assessment for water was categorized as high.

Short-chain chlorinated paraffins (SCCPs) are ubiquitous in the environment and might cause adverse environmental and human health effects. Little is known about the relative toxicity of different SCCP compounds especially during development. The objective of this study was to characterize and compare effects of seven SCCP groups at environmentally relevant levels, using a zebrafish (Danio rerio) model. Observations on malformation, survival rates at 96 h post fertilization (hpf), and hatching rates at 72 hpf indicated that the C10- groups (C10H18Cl4, 1,2,5,6,9,10-C10H16Cl6 and C10H15Cl7) were more toxic than the C12- groups (C12H22Cl4, C12H19Cl7 and 1,1,1,3,10,12,12,12-C12H18Cl8) and Cereclor 63L. The C10- groups were also more potent than C12- groups and Cereclor 63L in decreasing thyroid hormone levels. Among the three compounds within the C10- group, the compounds with less chlorine content had stronger effects on sub-lethal malformations but less effects on triiodothyronine (T3) and tetraiodothyronine (T4). Only C10H18Cl4 significantly decreased the mRNA expression of tyr, ttr, dio2 and dio3 at a dose-dependent manner suggesting that the specific mode of actions differ with different congeners. The mechanisms of disruption of thyroid status by different SCCPs could be different. C10H18Cl4 might inhibit T3 production through the inhibition effect on dio2. These results indicate that SCCP exposure could alter gene expression in the hypothalamic-pituitary-thyroid (HPT) axis and thyroid hormone levels. The mechanisms of disruption of thyroid status by different SCCPs could be different. Our results on the relative developmental toxicities of SCCPs will be useful to reach a better understanding of SCCP toxicity supporting environmental risk evaluation and regulation and used as a guidance for environmental monitoring of SCCPs in the future.

As a signatory of the Stockholm Convention and the largest developing country, China plays a very important role in implementation of the convention to reduce and finally eliminate persistent organic pollutants (POPs) in the world. In the past ten years after the enforcement in 2004, Chinese Government and scientists have made great progress on the study of POPs. The present work aims to provide an overview on recent studies on POPs in China, with particular focus on usage/emission inventory, residue inventory, and pollution status of POPs on national scale. Several legend (old) and new target POPs were comprehensively summarized with progress on inventory. Furthermore, several national scale monitoring programs have been selected for the occurrence, spatial and temporal trends of POPs in China, which are compared with Asian data and Global data. Based on the observed results, some important scientific issues, such as the primary and secondary distribution patterns, the primary and secondary fractionations, and air-soil exchange of POPs, are also discussed. It is proposed that more studies should be carried out for the new targeted POPs in future for both the national and global interests.

Simultaneous measurements of fine (PM 2.5 ) and coarse (PM 10 ) particles have been performed during three sampling period: summertime, early winter before the heating period, and during the winter heating. The sampling was done at an urban site, Harbin City, China, to apportion pollution sources and to investigate the impacts of weather parameters and emission sources on distribution patterns of PM 2.5 and PM 10 and their chemical compositions. Two chemometric techniques, hierarchical clustering analysis (HCA) and discriminant analysis (DA), and a receptor model (PMF5) were applied. The average mass concentrations of fine and coarse particles during the whole study period (i.e. annual averages), were 82.4 μg/m 3 and 120.1 μg/m 3 , with relative humidity and wind speed being the main factors influencing distribution patterns of PM 2.5 and PM 10, while sum of major ions ( NO 3 − , NH 4 + , SO 4 2 − ), and organic carbon (OC) were the greater contributor to total mass concentrations. According to DA, the distribution patterns of PM 2.5 and PM 10 during the winter heating period were distinct but overlapping in summer and early winter before heating, implying that, PM 2.5 and PM 10 were originated from different sources during the winter heating period but from similar sources during the other two sampling periods. This claim was further supported by PMF results. Canonical discriminant function coefficients of DA have shown species such as OC, EC, SO 4 2 − , NO 3 − , Cl − , Ti, Sr, Ca 2+ , Ni, and Ba to be good predictors/discriminants responsible for the differences between the three sampling periods. HCA visualized the interrelations among the source markers, while the PMF5 modeling confirmed HCA findings.

In this study we investigated the distribution patterns, infiltration and health risk assessment of PM2.5-bound PAHs in indoor and outdoor air done in Harbin city, northeastern China. Simultaneous indoor and outdoor sampling was done to collect 264 PM2.5 samples from four sites during winter, summer, and spring. Infiltration of PAHs into indoors was estimated using Retene, Benzo [ghi]perylene and Chrysene as reference compounds, where the latter compound was suggested to be a good estimator and subsequently used for further calculation of infiltration factors (IFs). Modeling with positive matrix factorization (PMF5) and estimation of diagnostic isomeric ratios were applied for identifying sources, where coal combustion, crop residues burning and traffic being the major contributors, particularly during winter. Linear discriminant analysis (LDA) has been utilized to show the distribution patterns of individual PAH congeners. LDA showed that, the greatest seasonal variability was attributed to high molecular weight compounds (HMW PAHs). Potential health risk of PAHs exposure was assessed through relative potency factor approach (RPF). The levels of the sum of 16 US EPA priority PAHs during colder months were very high, with average values of 377 ± 228 ng m(-)(3) and 102 ± 75.8 ng m(-)(3), for the outdoors and indoors, respectively. The outdoor levels reported to be 19 times higher than the outdoor concentrations during warmer months (summer + spring), while the indoor concentrations were suggested to be 9 times and 10 times higher than that for indoor summer (average 11.73 ± 4 ng m(-3)) and indoor spring (9.5 ± 3.3 ng m(-3)). During nighttime, outdoor PAHs revealed wider range of values compared to datytime which was likely due to outdoor temperature, a weather parameter with the strongest negative influence on ∑16PAHs compared to low impact of relative humidity and wind speed.

Limited studies focus on the occurrence, removal rate and seasonal variation of substituted diphenylamine antioxidants (SDPAs) in surface water and wastewater in China. In this paper, the detection method of SDPAs was established by the ultra-performance liquid chromatography-tandem mass spectrometry. Daily variations suggested that significant variations were found for the concentrations of some SDPAs in the influent. It was found that the SDPAs could be detected in all the effluent samples and C8/C8-DPA was the predominant compound in two WWTPs. The levels of most SDPAs in the effluent were much lower than that of influent, with the removal efficiencies of total SDPAs ranged from 57.9% to 84.2%. There were significant differences with the SDPA concentrations in the influent between different seasons. Higher concentrations of SDPAs were found at downstream than those of upstream. The results of this study provide more environmental occurrence data and new insights into the research on the environmental fate of these compounds.

To investigate the seasonal variation of organophosphate esters (OPEs) in air particulate matter (PM) and the corresponding influence factors in indoor environment, 104 indoor PM samples were collected in a test home, Harbin, China, from March 2017 to March 2018. The Σ12OPEs concentrations ranged from 0.41 ng/m3 to 940 ng/m3. Tris(1-chloro-2-propyl) phosphate (TCIPP) was the most abundant OPE and accounted for 83.2% of the total OPEs. The Σ12OPEs concentrations in spring and summer were higher than those in autumn and winter. Outdoor total suspended particles (TSP) were the main factor that affected the concentration variation of OPEs in PM samples in the test home. Comparisons of the gas/particle (G/P) partitioning equilibrium models indicated that the Dachs-Eisenreich (D-E) model estimates were more reliable than the other models in this study. The particle fractions of OPEs with log KOA > 10.51 that predicted by all four models generally well matched the measured OPE particle fractions in the literatures. To OPEs with lower molecular weight, inhalation was the main exposure route and ingestion contributed mostly to OPEs with higher molecular weight. In addition, the estimated daily intakes (EDIs) and carcinogenic risks (CRs) posed by OPEs were all below the recommended values, indicating that the current OPE levels in the test home were within the safe thresholds.

While infants are developing, they are easily affected by toxic chemicals existing in their environments, such as semi-volatile organic compounds (SVOCs): phthalates, polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs), and organophosphate esters (OPEs). However, the specific living environment of infants, including increased plastic products and foam floor mats, may increase the presence of these chemicals. In this study, 68 air, dust, and window film samples were collected from homes, with 3- to 6-month-old infant occupants, to analyze phthalates, PAHs, PBDEs, and OPEs. High detection rates and concentrations suggest that these SVOCs are widespread in infant environments and are associated with cooking methods, smoking habits, the period of time after decoration, and room floors. The partitioning behavior of SVOCs indicates that the logarithms of the dust/gas-phase air partition coefficient (logKD) and the window film/gas-phase air partition coefficient (logKF) in homes are not at an equilibrium state when the logarithm of the octanol/air partition coefficient (logKOA) is less than 8 or greater than 11. Considering the 3 exposure routes, ingestion and dermal absorption have become the main routes of infant exposure to phthalates and OPEs, and ingestion and inhalation have become the dominant routes of exposure to PAHs and PBDEs. The total carcinogenic risk of SVOCs, which have carcinogenic toxicities, via ingestion and dermal absorption for infants in homes exceeds the acceptable value, suggesting that the current levels of these SVOCs in homes might pose a risk to infant health.

Brominated flame retardants (BFRs), including polybrominated diphenyl ethers (PBDEs) and novel non-BDE flame retardants (NBFRs), were analyzed in Chinese air during China's POPs Soil and Air Monitoring Program Phase I (SAMP-I) and Phase II (SAMP-II). The levels of Σ12PBDEs and Σ6NBFRs in urban sites were significantly higher than those in rural sites and background sites. The higher detection rate and concentrations of high molecular weight PBDEs and NBFRs in Phase II indicated the changing of the commercial pattern of BFRs after the phase out of PBDEs in China. Temperature was the major factor affecting the seasonal variations of molecular weight BFRs in atmosphere. A significant correlation between BFRs concentration and gross domestic product (GDP) was observed, with the GDP parameter explained 59.4% and 72.7% of the total variability for Octa-BDEs and low molecular weight NBFRs, respectively. Our findings indicated an evolving commercial usage of BFRs from SAMP-I to SAMP-II, i.e. shifting from lower molecular weight to higher molecular weight congeners in China.

Benzophenone (BP)-type UV filters are commonly used in our daily life. 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-HBP), 2,4-dihydroxy benzophenone (BP-1), 2,2',4,4'-tetrahydroxy benzophenone (BP-2) and 2,2'-dihydroxy-4-methoxy benzophenone (BP-8) were measured in urine samples from Chinese young adults. The results indicated that Chinese young adults were widely exposed to BP-3, BP-1, and 4-HBP, with the median concentrations of 0.55, 0.21, and 0.08 ng/mL, respectively. No significant difference was found between males and females, between urban and rural population. The correlations between urinary concentrations provided important indications for sources and metabolic pathways of target compounds. The estimated daily excretion doses of BP-3, 4-HBP, BP-1, BP-2 and BP-8 were 27.2, 2.24, 5.86, 0.76 and 0.30 ng/kg-bw/day, respectively. The ratio of exposure to excretion must be considered for the exposure assessment with chemicals based on urine measurement. This is the first nationwide study on BP-derivatives with young adults in China.

Indoor environment is an important source of human exposure to several toxicants, such as brominated flame retardants. Indoor dust samples were collected in winter season in 2010, which covered 23 provinces across China, for the analysis of polybrominated diphenyl ethers (PBDEs). Concentrations of PBDEs (Σ14PBDEs) ranged from 8.92 to 37,500 ng/g, with the mean of 3520 ng/g. BDE-209 was the most dominate congener, followed by BDE-183, BDE-47 and BDE-99. PBDE concentrations and the longitude were significantly correlated (p0.05), which was consistent with the status of social-economic development and human activities. The results of exposure to PBDEs through dust ingestion and dermal absorption indicated that the toddlers had the highest exposure dose, with the median value of 6.0 ng/kg-bw/day. According to the hazard quotients, health risk of PBDEs via dust ingestion in China is currently acceptable. Monte Carlo simulation was implemented to quantify the uncertainty and sensitivity of exposure models for determining the most influential variables. The results suggested that more specific and accurate parameters should be used for dust ingestion and dermal absorption exposure models in future.

Surfactants are widely used in household and industrial products for cleaning and/or solubilization in our daily life. Therefore, they are finally discharged into wastewater treatment plants (WWTPs), which may be the major point pollution source for environment if they were not completely removed during wastewater treatment. In this study, two typical industrial and domestic WWTPs with different wastewater treatment technologies were considered for the topic. Totally, two types of surfactants were analyzed in 24 h influent and each processing unit effluent. Four linear alkylbenzene sulfonates (LASs) with the alkyl chain from C10 to C13, and two benzalkonium chlorides (BACs) with the alkyl chain of C12 and C14 were selected as target compounds. The total concentrations of LASs in influent varied from 19.2 to 1889 μg/L and LAS-C11 and LAS-C12 were the predominant compounds with the concentration from 6.01 to 641 μg/L and 8.02–674 μg/L, respectively. The total concentrations of BACs were much lower than those of LASs, with the concentration ranging from 0.00935 to 1.85 μg/L. Significant positive correlations were observed between concentrations of LASs and BACs in influent, indicating their same and/or similar sources. Compared with the concentration of influent, the concentration of effluent was much lower, indicating the high removal efficiency by the two wastewater treatment processes. Biological treatment unit and cyclic activated sludge system were the main treatment units for the removing of surfactants, which suggested that these two types of surfactants can be easily degraded under aerobic condition. Seasonal variation indicated that the removal efficiencies of surfactants in autumn were a little higher than those in winter. The results of this study provided new insights into the environmental fate of surfactants in wastewater treatment system.

Background/aim Collision of Epstein-Barr virus (EBV)-associated lymphoepithelioma-like carcinoma (LELC) with non-Hodgkin's lymphoma of the stomach is extremely rare. Patients and methods Herein we report a case of LELC with primary diffuse large B-cell lymphoma (DLBCL) of the stomach in a 65-year-old patient. Results Gastric endoscopy showed a poorly differentiated adenocarcinoma of the stomach. The patient underwent radical gastrectomy, and histopathological examinations revealed the collision of LELC and DLBCL of the stomach. In situ hybridization showed that most carcinoma cells of LELC were positive for EBV-encoded small RNA (EBER) suggesting that the virus infection happened in the early stage of tumorigenesis, while DLBCL was negative. Conclusion This is the first report of collision of EBV-associated LELC with primary DLBCL of the stomach.

Aim Through analysis and summarization of clinicopathological features, immunohistochemical expression, pathological diagnostic criteria, prognostic and other factors in patients suffering from bladder neuroendocrine carcinoma (BNEC), a better understanding of BNEC could be achieved to provide solid evidence for clinicopathology and prognosis. Materials and methods The clinicopathological data of 39 cases of BNEC with up to 5-year follow-up data (median follow-up=650 days) were analyzed retrospectively based on immunohistochemical staining. Survival analyses were carried out using the Kaplan-Meier method and tested with the log-rank method. Multivariate Cox regression analysis was adopted to screen independent risk factors affecting patients' survival. In these 39 cases of BNEC, there were 26 cases of male patients, 13 female, with the proportion of male to female being 2:1. The ages of onset ranged from 44 to 86, with the median age being 62 and the average age 61.97 years, respectively. Histologically, referring to the WHO standard of neuroendocrine lung tumor classification, there were 7 cases of typical carcinoid tumors, 8 atypical carcinoid, 12 small-cell carcinomas and 12 large-cell carcinomas. In these cases there were 11 cases of featured urothelium carcinomas and 9 cases of adenocarcinomas. Results Immunohistochemical staining showed that, in these 39 cases of BNEC, the positive expression for the neuroendocrinic markers, including neural cell adhesion molecule 56 (CD56), synaptophysin (Syn), chromogranin A (CgA), neuron-specific enolase (NSE), thyroid transcription factor-1 (TTF-1), cytokeratin (CK) and cytokeratin 7 (CK7), accounted for 39/39, 27/39, 18/39, 39/39, 19/39, 10/39 and 8/39, respectively. In contrast, cytokeratin 20 (CK20), protein 63 (P63), human melanoma black 45 (HMB45), S-lfln protein 100 (S-100) and leukocyte common antigen (LCA) were all negatively expressed. During the follow-up period, 12 patients died. The 1-, 3- and 5-year overall survival (OS) rates were 76.92%, 74.36% and 69.23%. Conclusion BNEC is one of the most malignant tumors with severe invasiveness and poor prognosis. Immunohistochemistry revealed that CD56, Syn, CgA, NSE, TTF-1, CK, CK7, CK20, P63, HMB45, S-100 protein and LCA immune markers play important roles in diagnosis and differentiation. Many factors, including the patient's age, size and shape of the tumor, operative method, perineuronal invasion, vascular invasion, distant organ metastasis and pathological type, show great difference in influencing OS time of patients, among which the size of the tumor, no invasion, vascular invasion and distant organ metastasis are independent risk factors affecting prognosis (survival time). Radical cystectomy is the prior alternative to treat this tumor.

The present study investigated the environmental distribution and fate of low molecular weight (LMW) polychlorinated biphenyls (PCBs) in China using the ChnGIPERM (Chinese Gridded Industrial Pollutants Emission and Residue Model), in which the air-soil exchange, spatial-temporal variations and the heterogeneity of secondary emission and residue in the non-source areas were studied. The model simulated the temporal and spatial variations of the PCB28 concentration in soils and air which agreed well with historical monitoring data across China. The long-range atmospheric transport (LRAT) and temperature was identified as the major factor affecting the distribution patterns of the secondary emissions and residues. Soil residue was considered as important environmental fate of PCB28. However, the intensity of an emissions source and the distance with non-source area strongly affected the spatial and temporal variations of PCB28 residues in soil. Several factors strongly impacted the distribution characteristics and air-soil exchange of PCB28, including emission patterns, atmospheric transport, soil organic carbon (SOC), soil vertical transfer, ambient temperature, and precipitation.

The Songhua River is the third largest river in China and the primary source of drinking and irrigation water for northeastern China. The distribution of 16 priority polycyclic aromatic hydrocarbons (PAHs) in water [dissolved water (DW) and suspended particulate matter (SPM)], sediment, and soil in the river basin was investigated, and the associated risk of cancer from these PAHs was also assessed. The total concentration of PAHs ranged from 13.9 to 161 ng L(-1) in DW, 9.21 to 83.1 ng L(-1) in SPM, 20.5 to 632 ng g(-1) dw (dry weight) in sediment, and from 30.1 to 870 ng g(-1) dw in soil. The compositional pattern of PAHs indicated that three-ring PAHs were predominant in DW and SPM samples, while four-ring PAHs dominated in sediment and soil samples. The spatial distribution of PAHs revealed some site-specific sources along the river, with principal component analysis indicating that these were from pyrogenic sources (such as coal and biomass combustion, and vehicle emissions) and coke oven emission distinguished as the main source of PAHs in the Songhua River Basin. Based on the ingestion of PAH-contaminated drinking water from the Songhua River, cancer risk was quantitatively estimated by combining the Incremental Lifetime Cancer Risk assessment model and BaP-equivalent concentration for five age groups of people (adults, teenagers, children, toddlers, and infants). Overall, the results suggest that the estimated integrated lifetime cancer risk for all groups was in acceptable levels. This study is the first attempt to provide information on the cancer risk of PAHs in drinking water from the Songhua River.

There are two kinds of primary emissions of PCBs to the atmosphere; one is primary emissions due to intentionally produced PCBs (IP-PCBs), and the other is due to unintentionally produced PCBs (UP-PCBs). This paper presents UP-PCB emissions in China from 1950 to 2010. The total UP-PCB emissions in the 61 years were estimated to be 146.1 t, approximately 98.1% of which were from cement (132.5 t) and steel industries (6.3 t). The emissions from Chinese coking industry were 115 kg from 1950 to 2010, less than 0.1% of the total UP-PCB emissions in China. Both the temporal and spatial trends of these UP-PCB emissions were investigated. The UP-PCB emissions started to increase quickly at the middle of 1980s due to the fast and continuously developing cement and steel industries in China, and exceeded IP-PCB emissions possibly during the beginning of 2000s. The spatial pattern of UP-PCB emissions was in general consistent with the population distribution pattern, indicating the anthropogenic nature of the UP-PCB emissions. The gridded Chinese emission inventories for UP-PCBs from cement and steel industries on a 1/6° latitude and 1/4° longitude resolution were also compiled. The gridded UP-PCB emissions in 2005 were compared with PCB air concentrations measured by our group (IJRC-PTS) in 2005, and a significant correlation between these 2 datasets was found for the rural sites, but not for the urban sites. It is most likely that these UP-PCB emissions were a major source for PCB in Chinese rural air, and possibly responsible for the increase of PCBs in Chinese air as a whole from 2004 to 2008, reported in recent publications. To our knowledge, this is the first dataset of the Chinese UP-PCB emissions spanning 61 years from 1950 to 2010, and also the first gridded emission inventories for UP-PCBs on a national scale.