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Taking Liangshui River, the reclaimed water-receiving river in Beijing, as the research area, the types, detection frequencies, and concentrations of 16 antibiotics in water and sediment were analyzed, and their temporal-spatial variation and occurrence characteristics were discussed. The results showed that nine and 13 target antibiotics were detected in the water and sediment of Liangshui River, with the antibiotic concentration ranges of ND-116.68 ng·L -1 and ND-235.42 ng·g -1 , respectively. The main antibiotics in water were ofloxacin and clarithromycin, and the main antibiotic in sediment was ofloxacin. The total concentration of antibiotics in water and sediment showed a gradual decrease from the upstream to the downstream in the Liangshui River mainstream, and the concentration of antibiotics in tributaries was higher than that in the mainstream. The inflow of tributaries had an obvious impact on the antibiotic concentration in water for the Liangshui River but had little impact on its sediment. The total concentration of antibiotics in water and sediment during the dry season was generally higher than that during the wet season. The detected antibiotics with the highest concentration were quinolones in water during the wet season and macrolides in the dry season. Quinolones had the highest concentration in sediment in both seasons. The ecological risk assessment results showed that clarithromycin had a low risk in water in the dry season and sediment in both seasons, whereas the other antibiotics had no risk. The combined ecological risk and the most sensitive trophic level ecological risk assessment showed that all sampling sites had low risk or no risk, and the risk of the dry season was generally greater than that of the wet season. The risk values of some sampling points were close to the medium risk threshold during the dry season, which requires further attention.

Microbial communities play an important role in water quality regulation and biogeochemical cycles in lakes, and their community structure and function are affected by environmental factors. Therein, antibiotics affect the abundance, diversity, composition, and function of microbial communities. In this study, Baiyangdian Lake was selected as the study area. Sediment samples of 16 sites were collected in August 2018 and April 2019, respectively. Ultra-high performance liquid chromatography-mass spectrometry （HPLC-MS/MS） was used to determine the content of typical antibiotics-quinolones （QNs） in sediment. Through high-throughput sequencing technology, the structure and function of microbial communities was analyzed in the sediments to explore the spatiotemporal variation. Thereinto, redundancy analysis （RDA） was used to identify the key influencing factors of spatiotemporal variation of microbial communities. The results showed that： ① From August to April, the average ω （QNs） showed an increasing trend, and its mean value changed from 3.91 ng·g -1 to 6.34 ng·g -1 , with significant seasonal differences in oxolinic acid （OXO） and total QNs content （ P < 0.05）. ② In terms of temporal variation, the dominant bacteria were Proteobacteria and Chloroflexi. The relative abundance of Proteobacteria showed a decreasing trend, whereas Chloroflexi showed an increasing trend； at the genus level, the dominant bacteria genera in August were norank_ f__Anaerolineaceae and Thiobacilus , and the dominant bacteria genera in April were Acinetobacter and norank_ f_Anaerolineaceae, and the dominant bacteria genera had significant seasonal differences （ P < 0.05）. ③ In terms of temporal variation, the index of Simpson, Chao, Ace, and OTU number all showed an increasing trend, and the seasonal differences were significant （ P < 0.05）. ④ In terms of spatial variation, there were no significant spatial differences among functional genes of COG. In terms of temporal variation, there were significant seasonal differences in functional genes of energy production and conversion, carbohydrate transport and metabolism, transcription, cell wall/membrane/envelope biogenesis, and signal transduction mechanisms （ P < 0.01 and P < 0.05）. ⑤ Microbial community structure and functional genes were significantly correlated with QNs （ P < 0.01 and P < 0.05）, and QNs were the main influencing factors. Therefore, QNs were the main factor affecting the changes in microbial community structure and functional genes in sediments of Baiyangdian Lake. Thus, comprehensive control of antibiotic pollution in sediments should be further strengthened.

Organophosphates （OPEs） are widely used as flame retardants and additives and thus are commonly detected in the environment. In order to explore their environmental behavior, the concentrations of 13 OPEs in the surface water and sediment of Dongting Lake were analyzed using UPLC-MS/MS. The results showed that 11 OPEs were detected, with detection frequencies of 5.26%-100% and 58.3%-100%, and the concentrations of OPEs were 2.06-2 028 ng·L -1 and 19.6-2 232 ng·g -1 in water and sediment, respectively. Overall, contamination concentrations were ranked in descending order as follows： inflowing rivers, lake area, and outlet, whereas the spatial distribution of concentrations in sediment was inversely proportional to hydrodynamics. The concentration of OPEs in Dongting Lake was at a high level compared with that of domestic and foreign lakes. Among the detected 11 OPEs, tri-iso-butyl phosphate （TnBP） and （TiBP） were dominant in water, accounting for 52.3% and 22.4% of ∑OPEs, respectively. TPhP was the dominant OPEs in sediment, accounting for 31.2% of ∑OPEs. The correlation and principal component analysis indicated that OPEs pollution in Dongting Lake was mainly affected by industrial production emissions, fishery aquaculture, and atmospheric deposition. The assessment results of the risk entropy showed that most of the detected OPEs in water had relatively low ecological risks, whereas the ecological risk of 2-ethylhexyl diphenyl phosphate （EHDPP） at some sampling points requires further attention.

To understand the contamination characteristics and ecological risk of antibiotics in contaminated fields of pharmaceutical plants， samples of the surface soil， soil column， wastewater treatment process water， ground water， and residue dregs were collected from two typical antibiotic pharmaceutical plants in South and North China. A total of 87 commonly used antibiotics were quantified using ultrasound extraction-solid phase extraction and ultra-high performance liquid chromatography-mass spectrometry. The results showed that a total of 31 antibiotics of five classes were detected in all types of samples， and the maximum concentrations at each sampling point in the surface soil， soil column， residue dregs， wastewater treatment process water， and groundwater were 420 ng·g -1 ， 595 ng·g -1 ， 139 ng·g -1 ， 1 151 ng·L -1 ， and 6.65 ng·L -1 ， respectively. Most of the antibiotics were found in the surface soil， showing a decreasing trend with the depth of the soil column. The ecological risk assessment indicated that sulfamethazine， sulfaquinoxaline， tetracycline， chlorotetracycline， and D-sorbitol were at higher risk. Improving the efficiency of antibiotic removal from pharmaceutical wastewater and preventing production shop leaks are effective measures of controlling antibiotic contamination into and around fields in pharmaceutical plants.

Aiming to explore the spatiotemporal occurrence of organophosphate esters (OPEs) in the aquatic environment of Taihu Lake and to assess the relevant ecological risk, monomeric and oligomeric OPEs in the surface water and sediment of Taihu Lake were determined using solid phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry. The target monomeric OPEs included chlorinated OPEs, alkyl OPEs, and aryl OPEs. There was no significant difference in the spatial distribution of OPEs in water and sediment between the pollutant-impacted and less-impacted zones. The average concentrations of OPEs in summer and winter were, respectively, 752.7 and 498.5 ng·L -1 in water and 124.0 and 54.5 ng·g -1 in sediment, indicating an obvious seasonal difference, especially for the monomeric OPEs. The OPEs levels in both the water and sediment were ranked in the order of chlorinated OPEs > alkyl OPEs > aryl OPEs≈oligomeric OPEs. The pseudo-partitioning coefficients ( K ) of OPEs between the sediment and surface water of Taihu Lake were much higher in summer (0.05-4.17 L·g d ) compared to those in winter (0.02-3.47 L·g -1 ) compared to those in winter (0.02-3.47 L·g -1 ) and were significantly positively correlated with the lg K ow values of OPEs. Based on the median concentrations of OPEs in the water of Taihu Lake, the ecological risk of OPEs was assessed by risk quotient (RQ) values, which indicated a medium risk at an RQ level of 0.34 during winter and 0.35 during summer. The assessment results showed that the risk ranking of OPEs was consistent with that of their concentrations, and the monomeric OPEs posed a higher ecological risk in summer compared to that in winter. Although the ecological risk of oligomeric OPEs in this study was not serious and was lower than that of monomeric OPEs, it is an urgent requirement to conduct ecotoxicology studies on oligomeric OPEs in the future since available data is highly limited at present.

It is well known that conservation tillage can improve soil quality, such as soil organic matters. However, limited information on the conservation tillage impacts on pesticides has been reported, which is important to food security. To explore the specific effects of conservation tillage on herbicide residues in soils, parallel soil samples from seven sites under traditional tillage and conservation tillage were collected, respectively, in Jilin Province, Northeast China. The soil properties and characteristics of three herbicides(acetochlor, atrazine, and MCPA-Na) were measured. The results showed that conservation tillage significantly increased total organic carbon(TOC) content, soil water content, and the average particle size of soil aggregates[(2.1±0.1)%, (19.1±1.2)%, and (82.2±3.0) μm increased to(2.9±0.3)%, (22.3±1.5)%, and (97.2±4.2) μm, respectively]. The results also showed that different herbicides were correlated with different soil properties. For example, TOC content and soil water content were positively correlated with atrazine, whereas micro-aggregate content was negatively correlated with acetochlor. Therefore, the effects of conservation tillage on the three herbicide residues were different. For instance, conservation tillage significantly increased the residual amount of atrazine[from(3.8±0.3) ng·g -1 to (17.7±3.0) ng·g -1 ] in the Dongfeng site by increasing TOC content, whereas it significantly reduced the residual amount of acetochlor[from (50.6±10.3) ng·g -1 to (9.2±2.5) ng·g -1 ] in the Dehui site by increasing the average particle size of soil aggregates. Generally, this study suggests conservation tillage indeed affected herbicide residues in soils by affecting soil properties. However, the influence of conservation tillage on herbicide residue was dependent on the types of herbicides due to the complex effects of different soil properties on herbicide migration and degradation.

The current situation of antibiotic pollution in lakes is critical. At present, most of the previous studies on antibiotics in lakes have focused on the spatiotemporal distribution and risk assessment, while less attention has been paid to the source apportionment. Ultra-high performance liquid chromatography-mass spectrometry was used to determine the concentration of tetracyclines (TCs), sulfonamides (SAs), and quinolones (QNs) in the samples. The source apportionment and source-specific risk of typical antibiotics in the study area were analyzed using the combination of a PMF model and risk quotients (RQ). The results showed that ① the total concentrations of target antibiotics (Σ antibiotics) ranged from ND to 2635 ng·L -1 for surface water and from ND to 259.8 ng·g -1 for sediments. ② The spatial distribution of QNs in surface water decreased from west to east, SAs decreased from middle to north and south, and TCs increased from middle to north and south. In the sediment, QNs decreased from middle to east and west, whereas SAs and TCs increased from east to west. ③ Aquaculture was the major antibiotic source, accounting for the highest proportion (33.2%), followed by sewage treatment plants (29.2%), livestock activities (18.9%), and domestic sewage (18.7%). ④ The ecological risk assessment results showed that enrofloxacin and flumequine were at a medium-high risk level. ⑤ For the spatial distribution of source-specific risk, the results showed that the aquaculture at S1 was at a high risk level, whereas the source-specific risks for other sites were at a medium-low risk level. In terms of source types, aquaculture was at a medium-high risk level, whereas the other sources were at a medium-low risk level. Therefore, considering the major sources and source-specific risk level of antibiotics, more precise and scientific antibiotic risk control should be adopted in Baiyangdian Lake.

PAHs (polycyclic aromatic hydrocarbons) accumulated in arable soils have significant impacts on farmland quality and human health, which has attracted wide attention from scientists and the public. A total of 22 arable soil samples were collected from Taiyuan, an old industrial city, including three districts (industrial zones, hilly areas, and sewage irrigation area), and the contents of 21 PAHs were detected using the GC-MS method. The sources of PAHs in soils were analyzed using the diagnostic ratios (DRs) method and positive matrix factorization (PMF) model, and the soil health risks were analyzed using the incremental lifetime cancer risk (ILCR) model. The results indicated that the average concentrations of Σ 21 PAHs in arable soils of Taiyuan were 934.6 ng·g 16 and 787.7 ng·g PAHs in arable soils of Taiyuan were 934.6 ng·g -1 . Approximately 60% of sites in industrial zones, 13% in hilly areas, and 33% in the sewage irrigation area had high PAHs contents larger than 1000 ng·g -1 , respectively, which were lower than the soil pollution risk screening value of agricultural land stipulated in GB 15168-2018. 3-5 rings PAHs were the dominant components, accounting for~90% of the Σ 21 PAHs . Approximately 60% of sites in industrial zones, 13% in hilly areas, and 33% in the sewage irrigation area had high PAHs contents larger than 1000 ng·g -1 . The spatial distribution of PAHs showed that more severe PAHs pollution in the soil occurred in industrial areas than that in the other two districts. The DRs suggested that the combustion of coals, bio-masses, and traffic emissions were the dominant sources for PAHs pollution in arable soils in Taiyuan. The simulation results of the PMF model indicated that the sources and contribution rates of PAHs in cultivated soils were coal and biomass burning sources (59%), traffic sources (22%), and coking sources (19%). The risk assessment confirmed that the arable soils in Taiyuan had high potential carcinogenic risks; thus, more attention should be paid to the PAHs pollutions in arable soils.

Persistent organic pollutants (POPs) in the environment have the characteristics of persistence, bioaccumulation, teratogenicity, carcinogenicity, and mutagenicity. Long-term exposure of low-content POPs will also have a certain impact on marine ecosystems and human beings. The contents of three typical persistent organic pollutants[polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polycyclic biphenyls (PCBs)] of surface sediments were analyzed using gas chromatography and mass spectrometry (GC-MS) to assess the pollution characteristics of persistent organic pollutants in Boao coastal waters. The distribution and source of persistent organic pollutants were analyzed in this study, and the ecological risk was assessed using three different methods:the effect interval low/median method (ERL/ERM), mean effect interval median quotient method (M-ERM-Q), and mean potential impact concentration quotient method (M-PEC-Q). The results indicated that the contents (measured by dry weight) of ΣPAHs, ΣOCPs, and ΣPCBs in the study area were 4.5-367.50, 3.99-175.30, and ND-2.89 ng·g -1 , respectively, which were at a low level, and the overall distribution showed a trend of gradually increasing toward the sea. The results of POPs source analysis showed that the PAHs in the study area were mainly from the combustion of wood and coal. Among OCPs, the HCH was mainly from lindane, the historical land-based input had been completely degraded, and the DDT was mainly the traditional DDTs pesticides, with additional continuous DDT input. The PCBs were primarily pentachlorobiphenyls, which might have come from the release of paint on the bottom of the hull in the early stage of shipping and the peeling off of paint from old ships. The ecological risk assessment results showed that there was little difference among the assessment results of the three methods, which showed that only phenanthrene monomer of PAHs in the study area had a slight negative impact, and the DDT and the γ- HCH among PAHs would cause great ecological risk, whereas PCBs and other pollutants would not cause ecological risk. On the whole, the possibility of comprehensive ecological risk caused by the three pollutants was very small.

Sewage treatment plants (STPs) are one of the crucial barriers for the environmental emission of steroid hormones. Insights into the occurrence and fate of different categories of steroid hormones in STPs could provide theoretical support for improving steroid removal by STPs. The present study investigated 22 steroid hormones in each treatment process of two STPs located in Wuxi via eight monthly sampling campaigns and compared the efficacy of Anaerobic-Anoxic-Aerobic (A 2 /O) and reversed A 2 /O treatments. The results showed that the total steroid concentrations in the influent and effluent were 27.7-256.8 ng·L -1 and 5.7-211.0 ng·L -1 , respectively, and 36.3-123.6 ng·g -1 in the excess sludge. Androsterone, androstenedione, estrone, estriol, and progesterone were the main species detected in the STPs. The concentrations of most steroids increased with the rise of rainfall and temperature, whereas the removal rates were not significantly different between winter and summer. Secondary and tertiary treatment processes showed better performance in steroid removal compared with that in the primary treatment; however, reversed A 2 /O did not show advantages over traditional A 2 /O. The organic-normalized partition coefficients (lg K oc ) of steroids ranged between 2 and 4.5. The values of lg K oc in STP A were slightly greater than those in STP B, indicating that the partition behavior of steroids may influence their treatment efficacies.

In order to understand the occurrence characteristics and ecological risks of pharmaceuticals and personal care products (PPCPs) in surface water and sediments of Hongze Lake and Gaoyou Lake in the lower reaches of the Huaihe River, 43 surface water and sediment samples from 23 sampling sites were collected, and 61 PPCPs were detected in the samples. The concentration level and spatial distribution of target PPCPs in Hongze Lake and Gaoyou Lake were analyzed, the distribution coefficient of typical PPCPs in the water/sediment system in the study area was calculated, and the ecological risk of target PPCPs was evaluated using the entropy method. The results showed that the PPCPs in surface water of Hongze Lake and Gaoyou Lake were 1.56-2534.44 ng·L -1 and 3.32-1027.47 ng·L -1 , respectively, and those in sediment were 1.7-926.7 ng·g -1 and 1.02-289.37 ng·g -1 , respectively. The concentrations of lincomycin (LIN) in surface water and doxycycline (DOX) in sediment were the highest, and antibiotics were the main components. The spatial distribution of PPCPs was higher in Hongze Lake and lower in Gaoyou Lake. The distribution characteristics of typical PPCPs in the study area showed that typical PPCPs tended to stay in the water phase, and there was a significant correlation between lg K oc and lg K d , indicating that total organic carbon (TOC) played an important role in the distribution of typical PPCPs in the water/sediment system. The ecological risk assessment results showed that the ecological risk of PPCPs to algae in surface water and sediment was significantly higher than that of fleas and fish, the ecological risk value of PPCPs in surface water was higher than that in sediment, and the ecological risk of Hongze Lake was higher than that of Gaoyou Lake.

Per- and polyfluoroalkyl substances (PFASs, n =22), including emerging alternatives, in dust samples were analyzed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to study their pollution characteristics. These samples were collected from main and minor roads in Shijiazhuang. Some of the roads were located near sewage treatment plants and fire stations. The results showed that PFASs were ubiquitous in the road dust of Shijiazhuang; in particular, hexafluoropropylene oxide dimer acid (HFPO-DA), an alternative, was measured for the first time in China. The total concentrations of PFASs ranged from 2.62 to 137.65 ng·g -1 . Perfluorooctanoic acid (PFOA) was the dominant PFAS, followed by perfluorobutanoic acid (PFBA), HFPO-DA, and perfluorooctane sulfonic acid (PFOS). The highest and lowest levels of PFASs were observed in the northwest and southeast regions of Shijiazhuang, respectively. The compositions of PFASs were obviously different in road dust near sewage treatment plants and fire stations, especially for the types of emerging alternatives. Health risk assessment indicated that road dust intake had a low risk of human exposure to PFASs and emerging alternatives. Among the three routes (ingestion intake, inhalation intake, and dermal contact), ingestion intake was the main route for PFASs and emerging alternatives in road dust to enter the human body. Under the same exposure route, the exposure dose of children was higher than that of adults.

Karst wetland plays an important role in the ecological environment; however, due to the existence of karst pipeline, pollutants can threaten the underground environment through the highly developed karst pipeline. Therefore, understanding the pollution characteristics of the karst surface environment is the premise of pollution ecological risk assessment and prevention. In this study, 24 organochlorine pesticides (OCPs) were analyzed to study the concentration, composition, source, and risk of OCPs in water and surface sediments in the Huixian Wetland of Guilin. The results showed that:the concentration of OCPs in water ranged from 3.17 ng·L -1 to 92.50 ng·L -1 , and the concentration of OCPs in sediment ranged from 1.16 ng·g -1 to 219.52 ng·g -1 , showing the main pollution characteristics of HCHs and DDTs. The concentration of OCPs in water was higher in the wet season than that in the dry season. The concentration of OCPs in sediments was higher in the dry season than that in the wet season. The isomer ratios revealed that OCPs in the study area were mainly derived from long-term degradation residues, and some sites had new input of lindane. Based on Monte Carlo simulation, the human health risk assessment of the study area showed that the 95% quantile carcinogenic risk of OCPs in water was greater than 1×10 -6 , with potential but acceptable health risk. The non-carcinogenic risk was lower than 1, which indicated that the level of OCPs residues in the water in the study area was not enough to cause non-carcinogenic risk to the human body.

Sediment is the main storage medium of antibiotics in a water environment, and a growing body of research has focused on the distribution behavior of antibiotics in water-sediment. However, most of the previous studies were based on laboratory simulation, and less attention was paid to the distribution behavior of antibiotics in a natural water environment and its correlation with environmental factors. Thus, the surface water and sediment in Shijiazhuang were taken as the research object for this study. The temporal and spatial distribution characteristics of quinolone (QNs) antibiotics in Shijiazhuang water were analyzed by using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS), calculating the distribution coefficients of quinolone (QNs) antibiotics in water and sediment, and confirming the main environmental factors influencing the distribution coefficient in natural water. The results showed that:① the content of ΣQNs in water and sediment ranged from 8.0 to 4.4×10 3 ng·L -1 and 16 to 2.2×10 3 ng·g -1 in Shijiazhuang water, whereas the primary QNs in water and sediment were enrofloxacin (ENR) and ofloxacin (OFL), respectively. ② The total concentrations of ΣQNs in Shijiazhuang water showed a tendency of being higher in December (1.0×10 4 ng·L -1 ) than in April (5.5×10 3 ng·L -1 ), and QNs in sediment were also higher in December (7.8×10 3 ng·g -1 ) than in April (6.2×10 3 ng·g -1 ). ③ The distribution coefficient of QNs in Shijiazhuang water varied from 34 to 2.9×10 5 L·kg -1 and showed a trend of being greater in December than in April. ④ The results of correlation analysis showed that total nitrogen (TN), nitrate nitrogen (NO 3 - -N), nitrite nitrogen (NO 2 - -N), and ammonia nitrogen (NH 4 + -N) were significantly correlated with most distribution coefficients of QNs[OFL, norfloxacin (NOR), ENR, difloxacin (DIF), and oxolinic acid (OXO)], whereas temperature ( T ), total organic carbon (TOC), and total dissolved solids (TDS) were significantly correlated with individual distribution coefficients of QNs[marbofloxacin (MAR) and DIF]. Therefore, the eutrophication level of water affects the distribution behavior of antibiotics in water-sediment.

Through the investigation and detection of the surface water and sediments of Luoma Lake, the structure and occurrence characteristics of PFASs (perlyfluoroalkyl substances) in the two types of media were analyzed, and the principal component analysis method was used to analyze the characteristics of such substances in the surface water. The source was analyzed, and the potential health risks of such substances were evaluated using the risk quotient method. The results showed that a total of 13 PFASs were detected in the surface sediments of Luoma Lake, and one more species was detected in the surface water (PFTeA); ρ (ΣPFASs) in the surface water ranged from 46.09 to 120.34 ng·L -1 , and ω (ΣPFASs) in sediments ranged from 2.22 to 9.55 ng·g -1 . PFPeA was the major component in surface water, and the mass fraction of PFPeA was 38%. PFBA was the major component in sediment, and the mass fraction of PFPeA was 61%. The multi-media PFASs in Luoma Lake were mainly short-chain substances; the high concentration area of PFASs in the surface water of Luoma Lake was concentrated and distributed at the mouth of the northern rivers. Its concentration showed a decreasing trend from north to south, and the content of PFASs in the sediments showed a decreasing trend from southwest to northeast. The distribution of ΣPFASs, PFBA, and PFOS in the sediments of Luoma Lake and the TOC content in the sediment were related; the principal component analysis showed that the PFASs in the surface water of Luoma Lake were mainly from textile flame retardant, rubber product emulsification, food packaging processes and paper surface treatment industries, the metal electroplating industry, and leather and textile manufacturing industries. PFASs in the surface water of Luoma Lake were at a relatively low health risk level.

Surface soil samples collected at 18 sites from the northeast Tibetan Plateau were used to analyze perfluoroalkyl substances (PFASs) via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to study the concentration levels and sources of PFASs. The results showed that 11 PFASs were detected in the soil, and the ω (Σ 11 ) ranged from 0.043-1.573 ng·g PFASs with an average concentration of 0.398 ng·g -1 . PFBA displayed the highest concentration level with a mean content of 0.164 ng·g -1 , whereas PFHxA was at the lowest level (0.005 ng·g -1 ). The concentrations of the other PFASs were similar to each other (0.011-0.057 ng·g -1 ). The concentrations of the other PFASs were similar to each other (0.011-0.057 ng·g -1 ). Generally, PFASs contents in the west and north were higher than that in the southeast, and the alpine condensation effect existed for PFBA. The principal component analysis showed that PFASs in surface soils in the northeast Tibetan Plateau region mainly originated from the atmospheric transport of PFASs and their precursors. Few areas were affected by direct emissions of point source pollution, and the main sources were the industrial production of metals/minerals and other human activities.

Polycyclic aromatic hydrocarbons (PAHs) are of concern globally because of their carcinogenic, teratogenic, mutagenic, and bio-accumulative effects. Northern China is one of the regions in China with a high density of lakes; however, the lake aquatic environment is becoming seriously deteriorated, especially from PAH pollution due to the intensification of human activities during the past 100 years. Therefore, the spatial distribution and historical changes in PAHs in lake sediments from northern China were analyzed to indicate their response to anthropogenic emissions and pollution reduction actions. The ω (PAHs) in lake sediments ranged from 18.2 to 1205.0 ng·g -1 , and low molecular weight PAHs were the dominant compounds. PAH concentrations increased from the 1950s to a peak level in the 2000s, which was induced mainly by increased energy consumption and rapid economy development, with PAH levels decreasing subsequently in the last 10 years due to craft improvement of wastewater treatment plants and the promotion of new energy policies. Spatially, PAHs pollution in Northeast and North China was more serious than that in Northwest China due to the higher level of economic development and energy consumption. Source apportionment results revealed that historical PAH emissions transferred from biomass combustion to a mixture of coal and petroleum combustion. In addition, the results of ecological risk assessment showed that the synthetic sediment quality index (SeQI) of northern China ranged from 36 to 75, and North and Northeast China posed higher ecological risk than that in Northwest China, with phenanthrene (Phe), acenaphthylene (Ace), acenaphthylene (Acy), and dibenzo(a,h)anthracene (DahA) as the main risk contributors.

In this study, 50 surface water and sediment samples were collected from 25 sampling points in Qingpu District (including Taipu River basin, Jinze Reservoir, and Qingxi country park) in the Yangtze River Delta integration demonstration area, and 22 pharmaceuticals and personal care products (PPCPs) in the samples were analyzed using high-performance liquid chromatography tandem mass spectrometry (HPLC/MS-MS). The distribution characteristics, sources, and influencing factors of targeted PPCPs in the study area were studied in detail. The ecological and health risks of the target PPCPs were evaluated using the quotients method. The results showed that a total of 19 PPCPs were detected in the surface water and sediment samples from 25 sampling points in Qingpu District, with total concentrations ranging from 0.06 to 178.67 ng·L -1 and 0.07 to 37.68 ng·g -1 , respectively. The average value of sulfachloropyridazine (SCP) in the surface water was the highest with a concentration of 129.54 ng·L -1 , whereas the average value of sulfamethoxazole (SMX) in the sediment was the highest with a concentration of 70.62 ng·g -1 . The spatial distribution of the total amount of PPCPs showed a trend of Qingxi country park > Jinze Reservoir > Taipu River basin. Principal component analysis showed that the main sources of pollution were animal antibiotics used in aquaculture and the discharge of domestic sewage. There was a significant correlation between lg K oc and lg K d ( P <0.05), indicating that the organic carbon plays an important role in the distribution of the target PPCPs in water and sediments. The ecological risk assessment results revealed that the fungicides (TCC and TCS) in the surface waters showed a moderate risk to aquatic organisms of different trophic levels. The Qingxi country park and Jinze Reservoir were the regions with the highest ecological risks of PPCPs in surface water and sediment. The health risk entropy (HQ) of people of all age groups exposed through drinking was less than 1; however, with the continuous emission and accumulation of PPCPs, the pollution control of PPCPs in the environment still requires further attention.

To study the characteristics of polychlorinated biphenyls (PCBs) in waste residue-soil-vegetable in an e-waste dismantling area and the potential health risks to humans, three samples of e-waste residue were collected, and 10 and 18 samples were taken from farmland soil and vegetables (six lettuce, six green bean, and six cabbage samples), respectively, next to the waste residue. High-resolution gas chromatography-mass spectrometry was used to detect the content of PCBs in waste residue, soil, and vegetables. The results showed that the total PCBs levels were as follows:waste residue (11938 ng·g -1 , dw) > soil (45.54 ng·g -1 , dw) > vegetables (11.51 ng·g -1 , dw). The bio-sediment/soil enrichment factor values were as follows:lettuce samples (0.18) > green bean samples (0.05) > cabbage samples (0.01). There were 37 PCB identical homologues detected in the waste residue and soil, and 33 types were detected in vegetables, all of which were within the homologues detected in the waste residue and soil. Some homologues in the soil were correlated with cabbages ( P <0.05). The column chart of PCB chlorination number in waste residues, soil, and vegetables showed that low-chlorinated biphenyls from trichlorobiphenyl to pentachlorobiphenyl mass fraction accounted for the largest proportion, accounting for 77.92%, 59.73%, and 73.96%, respectively. The proportion in the soil was relatively low, with the overall proportion showing a downward trend with increasing rate of chlorine generation. The results of the health risk assessment showed that the total HQ of PCBs in the soil and vegetables exposed to adults (male/female) and children was less than 1, which was at an acceptable level. The total CR of PCBs in the soil and vegetables exposed to adults (male/female) and children all exceeded 1×10 -6 , which is at an unacceptable level, and the values for adults (male/female) were higher than those for children.

The residual content of organochlorine pesticides (OCPs) in soil and crops of typical agricultural land in the southern Leizhou peninsula were determined using gas chromatography-mass spectrometry (GC-MS). Additionally, the bioconcentration factors of organochlorine pesticides in eight crops were investigated, and the human health risk was evaluated. The results indicated that 10 types of OCPs were detected to varying degrees; HCHs and heptachlor were the main OCPs in the study area, with the residual contents of 23.83-111.51 ng·g -1 and 11.01-25.97 ng·g -1 in soil and 7.54-61.28 ng·g -1 and 3.96-30.97 ng·g -1 in crops, respectively. A small number of soil and crop samples were found to exceed the standard. The ratio of α -HCH/ γ -HCH was less than 1 in 87.50% of the soil samples, and β -HCH/ α -HCH was larger than 1. This indicates that the HCHs were probably derived from the recent use of lindane and historical residual pollution, whereas the heptachlor was mainly derived from underground insect pests and the application of termite control agents. The enrichment ability of OCPs was significantly different among different crops. The bioaccumulation capacity of vegetables was higher than that of fruit. Furthermore, bulb vegetables (leeks) were significantly stronger than other vegetables. A human health risk assessment of OCPs showed that OCP-combined pollution would not cause significant health risks to the population in the study area. However, the maximum value of HI in some crop samples was greater than 1, indicating that there were still potential risks, which should not be ignored.

The river water-groundwater interaction zone is an important area for the enrichment, degradation, and transformation of pollutants and other biogeochemical processes. The distribution characteristics of antibiotics, as organic pollutants of wide concern, in the interaction zone is essential for understanding the migration and transformation process of pollutants in the environment. Due to the sensitive changes in the redox conditions and special composition of sediments in the interaction zone, this study established an effective pretreatment method for extracting 22 antibiotics and four sulfonamide metabolites in the interaction zone, and optimized the initial state of the samples, extraction temperature, pH value of the extraction solution and organic extraction solvent. The content of antibiotics in the sediments of the river water-groundwater interaction zone and lower reaches of the Hanjiang River was also analyzed. The results show that the best recovery of the target compounds is obtained by using pH 3 acetonitrile/Na 2 EDTA-Mcllvaine buffer(1:1, volume ratio) to digest and extract the unoxidized sediment samples at 40℃ three times using a microwave. A total of 11 antibiotics are detected in the sediments of the interaction zone in the lower reaches of the Hanjiang River, among which oxytetracycline and ofloxacin are the main compounds with the highest concentrations of 6.77 ng·g -1 and 5.81 ng·g -1 , respectively. The vertical distribution of antibiotics in different sediment profiles is significantly different, which may be related to the lithology of sediments, physicochemical properties of antibiotics, and interaction between surface water and groundwater.

A total of 22 antibiotics and 16 polycyclic aromatic hydrocarbons(PAHs) in sediments before and after desilting in typical areas(fish ponds and open water) of Baiyangdian Lake were analyzed using HPLC-MS/MS and GC/MS(high performance liquid chromatography and gas chromatography coupled with mass spectrometry), to evaluate their potentially risks to the ecological environment. The results showed that the contents of 22 antibiotics in Baiyangdian Lake sediments ranged from 0 to 52.89 ng·g -1 , in which the quinolones content was the highest. After dredging treatment, the average content of antibiotics in Nanliuzhuang open water area decreased from 46.25 ng·g -1 to 9 ng·g -1 (80.54% reduction), while the average content of antibiotic(19.07 ng·g -1 ) in Caiputai remained relatively stable. Therefore, the dredging treatment performed better in removing antibiotics from Naliuzhuang area. The total contents of 16 PAHs in sediments ranged from 23.79 ng·g -1 to 329.40 ng·g -1 , in which Naphthalene was the highest(242.02 ng·g -1 ), while Fluoranthene was the lowest. The average content of PAHs in sediments in Nanliuzhuang decreased from 117.45 ng·g -1 to 50.49 ng·g -1 after dredging, while PAHs in Caiputai(57.98 ng·g -1 ) remained stable; the 57.01% reduction in PAHs in Nanliuzhuang open water indicated that dredging treatment exhibited stronger effects on PAHs variations in Nanliuzhuang compared to that of Caiputai. In addition, the ecological risk assessment showed that the risk of Enrofloxacin and Norfloxacin was high in area S2 of Nanliuzhuang open water, while PAHs exhibited relatively low ecological risk, in which the Naphthalene in area S1 of Fuhe river posed medium ecological risk while the remaining produced low ecological risks. The results indicated that quinolone antibiotics in sediments of the un-dredged area of Baiyangdian Lake should be monitored due to its higher ecological risk.

Rapid urbanization and industrialization may potentially impact the spatial distribution and transmission of polyfluoroalkyl substances (PFASs). Tianjin, a typical industrialized city with a high urbanization level around Bohai Bay, was selected to evaluate the spatial distribution and ecological risks of PFASs. Water and soil samples were systematically collected and analyzed by using solid-phase extraction and high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS-MS) methods. The results showed that all 12 PFASs were detected in water and soils, and the detection rates of the other congeners were low. The concentrations of ΣPFASs in water ranged from 3.93 to 357.85 ng ·L -1 , and the levels of ΣPFASs in soils ranged from 4.60 to 63.85 ng ·g -1 . PFBA was the major component in water and soils, and the contribution of PFBA was 37% and 67% in water and soils, respectively. The spatial difference in ΣPFASs in the water bodies was significant. ΣPFAS concentrations in the surface water were higher in the north (mean value of 63.83 ng ·L -1 ) than in the south (mean value of 51.71 ng ·L -1 ) and higher in the eastern coastal area (mean value of 71.36 ng ·L -1 ) than in the western area (mean value of 36.08 ng ·L -1 ). ΣPFAS concentrations from upstream to downstream of the rivers showed an increasing trend. The highest PFAS concentration was found in the Chaobai River, and the lowest was detected in the South Canal. The spatial distribution of PFASs in soils was higher in the south (mean value of 13.33 ng ·g -1 ) than in the north (mean value of 6.38 ng ·g -1 ) and higher in the eastern coastal region (mean value of 11.45 ng ·g -1 ) than in the western region (mean value of 6.94 ng ·g -1 ). The soil concentrations of ΣPFASs in the Haihe River Basin were the highest. The source analysis results showed that the emulsification of rubber products, food packaging process, paper surface treatment, fire extinguishing agent use, and electrochemical fluorination process in industrial production were the main sources of PFASs in the soils in the study area. PFOS/PFOA, PFOA/PFNA, and PFHpA/PFOA analyses showed that the main source of PFASs in water bodies was the degradation of precursors. ΣPFASs in a few areas originated from the direct emissions from production, but the atmospheric deposition was small. The results of the ecological risk evaluation indicated that the exposure concentrations of PFASs in water and soils in the study area were at a low ecological risk level. However, the long-term ecological effects of PFASs cannot be ignored because of their long-distance transport capability and high food chain (web) accumulation capability.

In this study, soil samples were collected from the eastern edge of the Qinghai Tibet Plateau in December 2019. The level and distribution characteristics of organophosphate esters (OPEs) in seasonal frozen soil were analyzed, and their sources were discussed. The results showed that the target analytes including tri-n-butyl phosphate (TnBP), tris(2-ethylhexyl) phosphate (TEHP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tri(2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), and tris-(2,3-dichloropropyl) phosphate (TDCPP) were detected with 100% frequency. Levels of Σ 7 OPEs in topsoil (0-10 cm) and sub topsoil (10-20 cm) were 146.7-348.7 ng·g -1 (mean:231.1 ng·g -1 ) and 206.5-333.2 ng·g -1 (mean:260.2 ng·g -1 ), respectively. The Σ 7 OPEs content level is comparable to that of urban soil,which is worthy of attention. TBEP and TDCPP were the most abundant compounds in the plateau soil. Point source emissions have significant influence on the spatial distribution of OPEs, and regional deposition of OPEs contributes to all sampling sites. The migration ability of different OPE compounds in soil was different. Stronger migration ability was observed for aromatic OPEs (TPhP) than chlorinated OPEs. Principal component analysis showed that the main sources of OPEs in plateau soil were atmospheric wet and dry deposition, manufactured consumer materials, and the release of OPEs from automobile interior decoration.

In this research, 29 surface sediments samples of three typical lake reservoirs (in Yuqiao Reservoir, Hengshui Lake, and Dahuofang Reservoir) in the Jin-Ji-Liao area were collected and investigated, and the contents of 16 polycyclic aromatic hydrocarbons were detected using GC-MS. The results show that the Sigma PAHs (ng·g -1 ) in the sediments were 337.3-1604.1 (mean value 820.0), 461.1-1497.5 (mean value 932.3), and 102.3-2240.5 (mean value 564.9), respectively. Compared with other domestic rivers and lakes, the pollution levels of the PAHs in the three typical lakes were all at a medium level. The three lakes and reservoirs had consistency in the ratio of the number of rings, which is primarily high. PAHs source analyses were carried out by the characteristic ratio and primary component analysis method, and the results show that three lakes reservoirs pollution were caused mostly by combustion sources (including petroleum, coal, and biomass combustion), with a few petroleum sources. Additionally, the pollution contribution ratio of incomplete combustion of gasoline and diesel oil was 51.4%, and the pollution contribution ratio of combustion of coal and firewood were 22.3%. The risk evaluation results indicate that PAHs in the surface sediments of Yuqiao Reservoir, Hengshui Lake, and Dahuofang Reservoir are generally at a medium and low level, but the monitoring of three types of substances, Flu, InP, and DahA, should be strengthened, and corresponding emergency measures should be taken.

Coal-fired power plants (CFPPs) and waste incineration power plants (WIPPs) represent a large portion of polycyclic aromatic hydrocarbons (PAHs) sources in the environment, among which halogenated PAHs (HPAHs) are more toxic to the human body compared with their corresponding parent PAHs. In the current work, we investigated the occurrence, formation mechanism, and toxicity effects of HPAHs in the coal and waste combustion products from three CFPPs and one WIPP. The results indicate that the contents of chlorinated PAHs (Cl-PAHs) in the fly ash from the CFPPs and WIPP were 1.06-1.67 ng·g -1 and 2.76 ng·g -1 , respectively, and the contents of brominated PAHs (Br-PAHs) in the fly ash from the CFPPs and WIPP were 26.4-44.2 ng·g -1 and 6.31 ng·g -1 , respectively. The HPAH contents in the fly ash from the WIPP were significantly higher than those from the CFPPs primarily due to the abundant plastics in the domestic waste, represented by polyvinyl chloride, resulting in the formation of Cl-PAHs during combustion. The HPAH contents in the fly ash from the pulverized coal-fired (PC) boiler were significantly higher than those from the circulating fluidized bed (CFB) boiler mostly due to the higher combustion temperature operated in the PC boiler. The HPAHs in the fly ash from coal combustion were predominantly 7-BrBaA and 9-ClPhe, and those from domestic combustion were predominantly 9-BrPhe and 2-ClAnt. In addition, the contents of 7-BrBaA and 9,10-Br 2 Ant in the coal combustion fly ash were significantly higher than those in domestic waste combustion fly ash, whereas 2-BrFle exhibited a contrasting profile. The content of Br-PAHs in the fly ash treated by semi-dry deacidification was twice that in dust removal fly ash but significantly increased in the chelating agent stabilization fly ash. The Pearson correlation analysis indicated the the formation mechanism of Cl-PAHs and Br-PAHs were the same but a secondary formation of HPAHs during the chelating agent stabilization of the fly ash was deduced. The TEQ values of the HPAHs in the fly ash (8.87×10 -3 -15.0×10 -3 ng·g -1 ) from the WIPP were similar to those in the fly ash from the CFPPs (10.0×10 -3 ng·g -1 ), which were significantly reduced in the fly ash treated by semi-dry deacidification due to the removal of 7-BrBaA. Moreover, the TEQ values of the HPAHs in the fly ash increased 5.4 times after the chelating agent stabilization. The ecological risk should be considered for the CFPP fly ash due to their massive amount of discharge and high TEQ values.

Short-chain chlorinated paraffins are persistent organic pollutants, and chlorinated paraffins were widely used as sizing agent in the paper industry. In order to investigate the levels and risk assessment of short-chain and medium-chain chlorinated paraffins in the paper mill plant, the surface soil and soil of different depths were collected.The concentrations, congener group profiles of short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in soil were determined by two-dimensional gas chromatography coupled with electron capture-negative ion mass spectrometry. The SCCPs and MCCPs concentrations were 42-3853 ng·g -1 and 34-2091 ng·g -1 . The chlorine contents were 59.9%-61.9% and 48.7%-52.8%. The concentrations of SCCPs and MCCPs were different in the soil collected in different sampling site. The concentration of SCCPs and MCCPs were relatively higher in soil of sewage treatment area and coating area. The CP levels in soil from the paper mill plant were at a high level compared with those in other regions. C 10 Cl 6-7 and C 14-15 Cl 5 were the main congener groups in most soil samples. The results of principal component analysis showed that the CP52 commercial products may be sources of SCCPs and MCCPs in the soil. The risk quotient (RQ) for SCCPs and MCCPs were assessed in soil of paper mill plant. The results showed that the RQ values for SCCPs in soil ranged from 0.01 to 0.73 which are the medium risk, and the RQ values for MCCPs in soil ranged from 0 to 0.07, which are the low risk. The human exposure values of children and adults are lower than TDI[10 μg·(kg·d) -1 ] in both cases. The health risks caused by non-dietary exposure under paper mill area are low.

In order to understand the sources and distribution characteristics of hexachlorobutadiene (HCBD) in the Yangtze River Delta (YRD), Beijing-Tianjin-Hebei (BTH), and Pearl River Delta (PRD), the emission sources, as well as their distribution in water and soil were analyzed based on the production levels of chlorinated hydrocarbons and wastewater discharge in the three regions. The results showed that the by-products of trichloroethylene (TCE) and tetrachloroethylene (PCE) and wastewater treatment plants were the main sources of HCBD in the three regions. In 2018, the total emissions of HCBD from by-products of TCE and PCE in the three regions were 498.46 t, among which the proportion of by-products of TCE was 66.9%. The HCBD emissions of the three regional industrial and domestic wastewater treatment plants were 628.9 kg and 254.6 kg, respectively. The emissions of HCBD from hydrocarbon chlorination production and wastewater treatment plants in YRD were significantly higher at 497.8 t and 648 kg, respectively, while the emissions from the two sources in BTH were 0.37 t and 125 kg, respectively, and in PRD they were 0.29 t and 110.3 kg, respectively. The average concentrations of HCBD in the natural water of YRD, BTH and PRD were 0.35, 0.25, and 0.64 μg·L -1 , respectively, and in the drinking water concentrations were 0.16, 0.09, and 0.04 μg·L -1 , respectively. The overall level of HCBD in urban drinking water was relatively low. The concentrations of HCBD in industrial soil were significantly higher than in farmland soil, at 9.3-24.6 ng·g -1 and 0.13-2.67 ng·g -1 , respectively. Similar to the situation in water bodies, HCBD pollution in the soil of YRD was the most serious, which was related to the fact that HCBD emissions in YRD were significantly higher than in BTH and PRD.

Ephedrine (EPH) is an alkaloid commonly used to relieve nasal congestion caused by colds, allergic rhinitis, rhinitis, and sinusitis, and to control bronchial asthma. It is also be used as a raw material in the manufacture of methamphetamine. Although the distribution of EPH in surface waters has been widely studied, its uptake, internal distribution, and toxicokinetic processing in exposed organisms have not been well investigated. In this study, we investigated the uptake, disposition, and toxicokinetics of EPH in zebrafish ( Danio rerio ) in a semi-static exposure system. EPH was consistently detected in zebrafish biological samples, with the highest concentrations of 84.97 ng·g -1 detected in the brain tissue of fish in the high treatment group. Over the 14-d exposure period, the relative abundance of mean concentrations of EPH in biological samples generally followed the order of brain > ovary > liver > intestine > muscle. The uptake rate constants ( K u ), elimination rate constants ( K e ), and half-lives of EPH in the biological tissues were in the ranges 0.23-570.31 L·(kg·d) -1 , 1.22-6.11 d -1 , and 0.12-0.57 d, respectively. The observed bioconcentration factor (BCF o ) and kinetically-derived bioconcentration factor (BCF k ) were similar, ranging 0.24-337.33 L·kg -1 and 0.13-316.43 L·kg -1 , respectively. These results are helpful for understanding the behavior of psychoactive substances in aquatic organisms and have directive significance for studying their toxicity and ecological risks to aquatic organisms.

Emerging contaminants including antibiotics and antibiotic resistance genes (ARGs) have been frequently detected in drinking water resources. In this study, the occurrence of antibiotics and ARGs in various environmental matrices in representative drinking water sources in Jiangsu Province and their influencing factors were explored. Five representative drinking water sources in northern, central, and southern Jiangsu were selected. Water, surface sediment, and epilithic biofilm samples were harvested near the water intakes of each water resource in December 2018 and June 2019. The concentrations and abundances of ten antibiotics, one integrase gene intl1 , and seven common ARGs were measured. The results suggest that the concentrations of the target antibiotics and ARGs are relatively low compared to previously reported data in China and elsewhere in the world. The target antibiotics were detected in all of the water sources. The concentrations of sulfonamides in the water, surface sediment, and epilithic biofilm ranged from not found (NF) to 37.4 ng·L -1 , NF to 47.3 ng·g -1 , and NF to 3759.1 ng·g -1 , respectively; the concentrations of quinolones in three matrices were NF-5.3 ng·L -1 , 0.4-32.5 ng·g -1 , and NF-4220.9 ng·g -1 , respectively. The detection rates of the ARGs including sul 1, sul2, tetW , and tetQ were 100%, among which the sulfonamides sul1 and sul2 showed the highest abundance. The absolute abundances of sul1 in the three matrices were 2.48×10 6 copies·L -1 , 3.54×10 7 copies·g -1 , and 1.44×10 9 copies·g -1 , respectively. The abundances of ARGs in the sediments and epilithic biofilms were comparable, and were much higher than in the water body. The phyla Bacteroidetes, Proteobacteris, Firmicutes, Verrucobacteria, and Actinomycetes have proven potential hosts for ARGs and might play an important role in the transmission and diffusion of resistance genes. This study offers baseline information on the presence of antibiotics and ARGs in the drinking water sources of Jiangsu Province, providing a significant theoretical basis for ARGs pollution control and safety guidelines for drinking water resources.

The pollution characteristics of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and phthalate esters (PAEs) in the surface sediments of Xiaoxingkai Lake were analyzed by GC-MS, and the main sources and biological toxicity risks of the pollutants were discussed. The results show that:① The content of PAHs in the sediments of xiaoxingkai lake ranged from 82.1 to 534.6 ng·g -1 , and the concentration of PAHs in the northwestern port of the lake was higher. The content of OCPs and PAEs in the sediments ranged from 4.8 to 50.4 ng·g -1 and 33.3 to 401.6 ng·g -1 , respectively. The concentration was higher in the southeastern lakes. ② PAHs in the sediments were dominated by 3-5-ring compounds (accounting for more than 85%), which were mainly combustion sources, among which the combustion of coal and firewood contributed 47%, the combustion of gasoline and diesel contributed 39%, and the oil product leakage contributed 14%. The OCPs were mainly HCHs (78%) from the use of new lindane and the input of a small amount of industrial HCHs. The PAEs were mainly dibutyl phthalate (DBP) and diethyl phthalate (2-ethyl hexyl) ester (DEHP; 94%), which were mainly derived from household garbage and common human articles. ③ Compared with other lakes in China, PAHs and PAEs in the sediments of Xiaoxingkai Lake are at a low pollution level, and there is no ecological risk at present, but some OCPs at some points present a moderate ecological risk.

With the acceleration of urbanization and industrialization, the content and pollution of polycyclic aromatic hydrocarbons (PAHs) in urban soils have been sources of widespread concern. Taking Shizuishan City as an example, the spatial distribution characteristics of PAHs in 156 surface soil samples (0-20 cm) from eight urban functional areas were analyzed. Single factor and Nemero composite indices, as well as a lifetime cancer risk increment model were used to evaluate PAHs pollution in soils. The sources of PAHs were analyzed using the positive matrix factorization (PMF) model. The results showed that the mean value of PAHs in the surface soil of Shizuishan City was 489.82 ng·g -1 and the coefficient of variation of 15 PAHs except for Pyr were more than 100%, indicating strong variation. The PAH contents of urban surface soils in different functional areas showed the following:traffic area (1217.61 ng·g -1 ) > industrial area (809.58 ng·g -1 ) > park (273.66 ng·g -1 ) > cultural and educational area (268.18 ng·g -1 ) > commercial area (240.05 ng·g -1 ) > agricultural area (226.81 ng·g -1 ) > medical area (211.90 ng·g -1 ) > residential area (183.49 ng·g -1 ). The Nemero composite index showed that 82.58% of the samples had no pollution, and the proportion of slight, mild, and moderate pollution were 6.45%, 4.52%, and 0.65%, respectively. Only 5.8% of the samples had serious pollution. The results of health risk assessment showed that skin contact and ingestion were the main routes of PAH exposure in soil, and the health risk was acceptable. Source analysis showed that the main sources of PAHs in Shizuishan City were traffic emissions, coal combustion, mixed biomass/heavy oil combustion, and oil sources, with contribution rates of 10.5%, 36.6%, 50.3%, and 2.6% respectively, and most of the high values were distributed in industrial or coal production areas. These results could provide reference for the study of soil pollution in industrial cities, and play an important role in preventing soil pollution, ensuring the environmental quality of the soil and human health and safety.

In recent years, quinolone antibiotics (QNs), which easily bioaccumulate in aquatic organisms, have been widely detected in lake ecosystems, and the bioaccumulation and trophic transfer behavior are obviously spatiotemporally different. In this study, the bioaccumulation and trophic transfer behavior of fourteen QNs in nine dominant fish species were studied, the correlation with environmental factors was analyzed, and the health risk of QNs was evaluated in Baiyangdian Lake. The results showed that the mass concentrations of ∑QNs in water varied from 0.7400 to 1590 ng·L -1 . Furthermore, the detected frequencies of flumequine (FLU), oxolinic acid (OXO), and ofloxacin (OFL) were higher, and the average mass concentration of FLU was the highest. The content of ∑QNs in fish ranged from 17.1 to 146 ng·g -1 , and the average contents of ciprofloxacin (CIP) and OFL were higher. The bioaccumulation factors (BAF) were in the range of 96.2 (BAF MAR )-489 (BAF CIP ) L·kg -1 , indicating the bioaccumulation of QNs was low in dominant fish species. The trophic magnification factors (TMF) of five QNs (enrofloxacin (ENR), FLU, marbofloxacin (MAR), norfloxacin (NOR), and OFL) varied from 0.714 (TMF MAR ) to 1.33 (TMF ENR ), indicating ENR exhibited trophic magnification, while FLU, MAR, and ∑QNs exhibited trophic dilution. The results of correlation analysis between environmental parameters and BAF/TMF showed that pH, T , SD, DO, COD, TP, TN, NH 4 + -N, NO 3 - -N, and PO 4 3- -P were significantly related to the bioaccumulation of QNs in fish. The results of human health risk showed that the hazard quotient (HQ) of CIP (0.0040-0.026) was significantly higher than that of other QNs (≤ 0.0050), and the hazard indices (HI) ranged from 0.0010 to 0.035, indicating a high level of health risk. Therefore, to reduce the health risk, the standard and residue limits of QNs should be set in Baiyangdian Lake.

Coastal tourism resorts have been developing rapidly in recent years, and the quality of their waterbodies directly affects human health. Perfluoroalkyl substances (PFASs) are found in every environmental medium and have garnered widespread social concern because of their potential ecological harm. This study investigated the contamination characteristics and potential ecological risks of 12 PFASs in the water and sediment of 20 coastal tourism resorts in Shandong Peninsula. The results revealed that all targeted pollutants were observed in the water and most sediment samples collected from the coastal tourism resorts. The sum of the 12 PFASs ∑PFASs averaged 67.91 ng·L -1 and 5.89 ng·g -1 in the water and sediment, respectively. The predominant compounds were perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) in both water and sediment. The ∑PFASs and its homologues concentration indicated the spatial variations in the water and sediment of different tourism resorts, and the values were higher in the tourism resorts near the city center and the industrial areas than in other areas. The partition coefficient ( K d ) of all the target compounds in the water/sediment system of different tourism resorts showed obvious differences. In addition, the K d of the compounds with longer carbon chains (C ≥ 7) generally had higher K d values, which suggests that long-chain PFAAs are prone to adsorption by sediment. Therefore, the discharge of municipal industrial wastewater and domestic sewage is the main source of contamination. The salinity of water and the total carbon contents of sediment did not show any effect on the partition of PFASs in the water/sediment system. PFOS and PFOA might have great potential ecological risks in the water environment of all tourism resorts.

To investigate the occurrence, distribution, and potential risks of pharmaceuticals and personal care products (PPCPs) in the South costal area of China, a total of 20 PPCPs in water and aquatic organisms (fish, crab, and shellfish), obtained from 7 coastal rivers of the Chaoshan area, were determined using solid-phase extraction (SPE) and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The results showed that up to 16 to 18 kinds of PPCPs could be detected in the rivers and aquatic organisms of the Chaoshan area, and the concentrations of PPCPs in the rivers and organisms ranged from 0.30-2223 ng ·L -1 to 0.143-80.3 ng ·g -1 , respectively, with a high detection rate for many pollutants. Significant differences were observed in the samples of water and organisms. The total concentration of PPCPs in the rivers of the Chaoshan area was in the order of Huanggang River > Lianjiang River > Huangjiang River > Longjiang River > Luohe River > Rongjiang River > Hanjiang River, with the dominance of sulfamethoxazole (SMX) and caffeine (CAF). The total concentrations of PPCPs in the aquatic organisms from the Huanggang River, Hanjiang River, Lianjiang River, and Luohe River were higher than the concentrations of PPCPs in the aquatic organisms from the Longjiang River and Rongjiang River, with a dominance of trimethoprim (TMP), SMX, and CAF. The total concentration of PPCPs in fish was significantly higher than that in crab and shellfish. The results of bioconcentration factor (BCF) showed that a variety of PPCPs were accumulated in the organisms from the Chaoshan rivers; among them, the BCF value in fish was higher, which was more likely to bioaccumulate than crabs and shellfish. The ecological risks in terms of risk quotient (RQ) for 12 typical PPCPs were assessed in the Chaoshan area. It was discovered that the risk for fleas and algae was significantly higher than that for fish. The RQ values of SMX, erythromycin (ERY), and sulfadiazine (SDZ) were all greater than 1, which posed potential ecological risks for algae in the Huanggang River and Lianjiang Rivers and for fleas in the Huangjiang River.

The concentration of polybrominated biphenyl ethers (PBDEs) in surface soil and atmosphere of e-waste dismantling sites in Taizhou city, Zhejiang Province was determined. The concentration ranges of ∑ 12 PBDEs in surface soil of e-waste dismantling site, farmland, and resident areas in Fengjiang Town (FJ) and Binhai Town (BH) were 21.8-1310 ng ·g -1 and 6.19-220 ng ·g -1 , respectively. No significant difference was observed in the distribution of PBDEs between the FJ and BH soil. The concentration range of ∑ 12 PBDEs in the atmosphere of FJ and BH were 262-3240 pg ·m -3 and 840-2990 pg ·m -3 , respectively. The median levels of PBDEs in the atmosphere of FJ and BH were 1410 pg ·m -3 and 840 pg ·m -3 in winter and 1590 pg ·m -3 and 1960 pg ·m -3 in summer, respectively. However, a significant difference was observed in the distribution of 11 PBDE congeners, except BDE-209, during winter and summer seasons. The migration trend analysis showed the differences between the soil and air of FJ and BH. The main migration trend of 3-5-BDEs was the volatilization from soil to atmosphere, and the increase in temperature promoted the volatilization of these PBDEs from soil to atmosphere in FJ. This indicated that the PBDEs in soil had become a major source of pollution emission and suggested that soil remediation should be carried out at the e-waste dismantling site and parts of farmland in FJ. Contrary to FJ, atmospheric deposition was the major migration trend of PBDEs and the soil was the main sink of PBDEs in BH. This indicated that e-waste dismantling site in BH could be a new source of PBDEs emission in this area.

To investigate the spatiotemporal differentiation of polybrominated diphenyl ethers (PBDEs) in urban water-source reservoirs and degradation sources of BDE homologues and their contributions, we analyzed the contents, pollution degrees, spatial distributions, hydrological period changes, inventories, profiles, and degradation source contributions of PBDEs in the surface sediments of Shanmei Reservoir and its inflowing river, Quanzhou, China. The results showed that the median ∑PBDEs (1072.1 ng ·g -1 ) in the inflowing river sediment was 6.7 times than that of the reservoir (160.4 ng ·g -1 ) and the total amount of ∑PBDEs in sediments per unit area (80.3 kg ·km -2 ) was 6.3 times than that of Taihu Lake and 188 times than that of the Great Lakes in North America. The pollution degrees of PBDEs in Shanmei Reservoir were more severe than those of most lakes and reservoirs at home and abroad, which was dominated by BDE-209 (84.5%-99.2%). Most of the sampling sites in the reservoir ( r 0.564-0.994, P <0.034) and the inflowing river ( r 0.953-1.0, P <0.000) had high similarity in the composition of PBDEs. Significantly positive correlations ( r 0.779-0.964, P <0.005) were observed between the reservoir entry area and river sampling sites, which were stronger than the other functional areas, indicating that the inflowing river was a major pollution source of PBDEs in the Shanmei Reservoir. The tail region of the reservoir had low correlations with the inflowing river ( r 0.454-0.915, P ≤0.128), and was relatively much more affected by Jiudu Town. The changes in hydrological period of the ∑PBDEs were relatively consistent at each sampling site ( r 0.617-0.714, P ≤0.077), but the impact of the changes in the hydrological period on the ∑PBDEs was not statistically significant ( P =0.178, Two-Way ANOVA). However, the site changes had a significant influence on the ∑PBDEs ( P =0.0001), and significant or nearly differences were observed between the reservoir entry area and other functional areas ( P 0.019-0.061), indicating that the spatial distribution variations of the PBDEs in reservoir sediments were greater than the changes in hydrological period. The natural degradation of the PBDEs gradually increased from the river to the reservoir entry area and then to the central reservoir area. The reductive debromination rates varied at different brominated levels, and some BDE homologues accumulated due to their slowly continued degradation velocities. Research on abundance ratios indicated that the lower brominated BDE homologues were mainly derived from the natural degradation of decabromodiphenyl ether by stepwise reductive debromination. Approximately 70% of Nona-BDE produced by Deca-BDE degradation could rapidly be degraded to form Octa-BDE. Approximately 85% of BDE-208 was derived from the degradation of BDE-209. During the degradation process from Octa-BDE to Penta-BDE, some Octa-BDE and Hexa-BDE homologues accumulated due to relatively slower degradation velocities, and the degradation rates of Penta-BDE to Tri-BDE were above 70%.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a group of manmade chemicals and are ubiquitously detected in aquatic environments. China is a major producer and consumer of PFASs. In this study, we investigated the occurrence and characteristics of PFASs in the surface sediments from three fluorine industrial parks in North China, the Xihe River in Liaoning Province (Fuxin Section), the Xiaoqing River in Shandong Province (Zibo Section), and the Yangtze River in Jiangsu Province (Changshu Section), using the UPLC/MS-MS method. The total concentration of PFASs (∑PFASs) in surface sediments of the Xihe River ranged from 15.8 to 2770 ng ·g -1 , and PFTeDA and HFPO-DA were the dominant pollutants. In the surface sediments of the Xiaoqing River, ∑PFASs ranged from 12.2 to 7853 ng ·g -1 , and PFOA and HFPO-DA were the dominant pollutants. In the surface sediments of the Yangtze river, ∑PFASs ranged from 9.20 to 35.9 ng ·g -1 , and PFTeDA and 6：2 FTS were the main pollutants. Sewage discharge from the industrial parks (point source pollution) was the main source of PFASs in three regions in this study. The PFAS content and composition in three regions varied significantly depending on the production capacity and industry type. There was no significant correlation between the content of PFASs and its components and the particle size and TOC of the sediments. The correlations between the components of PFASs indicated that the enrichment process of PFASs in sediments was impacted by various factors.

To assess the contamination by polycyclic aromatic hydrocarbons (PAHs) in organisms in the estuary of Changhua River in Hainan, we determined the content of 16 priority PAHs by gas chromatography and mass spectrometry (GC-MS). The composition, source, and potential edible risk of PAHs were studied. The results showed that the total PAHs of demersal fish (wet weight, same below), crustaceans, and pelagic fish were 5.52-787.98, 12.18-154.64, and 10.20-199.79 ng·g -1 , respectively, and the average contents were 83.21, 64.72, and 89.48 ng·g -1 , respectively. There were some differences in the content of PAHs in various organisms. The average content followed the order of pelagic fish > demersal fish > crustaceans. Compared with other areas in the country and abroad, the content of marine organisms'PAHs in the estuary of the Changhua River was above the medium level. The result of isomer characteristic ratio showed that the PAHs of 33 organisms mainly came from the combustion sources (petroleum combustion and biomass combustion) and petroleum sources. Moreover, demersal fish were greatly affected by combustion sources, while pelagic fish were greatly affected by petroleum sources. Human risk assessment indicated that the content of benzopyrene (BaP) was within the limits set by the European Union. Most of the organisms in the estuary of Changhua River were within the safe range of consumption, but the long-term consumption of these seafoods may pose a potential health risk (1.0×10 -5 ≤ILCR<1.0×10 -4 ).

This study concentrated on the 15 perfluoroalkyl substances (PFASs) in the coastal areas of China and South Korea, an urbanized area with intensive human activities. In total, 126 water samples and 125 sediment samples were collected and determined by HPLC-MS/MS. Fifteen PFASs were detected at least once in all the sites. The total concentrations of PFASs in water and sediment samples ranged from 6.75 ng·L -1 to 20982 ng·L -1 and from 0.229 ng·g -1 to 53.8 ng·g -1 (dw), respectively. The concentrations of PFASs in waters and sediments were relatively high in China, and PFOA was the predominant PFAS. In contrast, short chain compounds such as PFBA and PFPeA played a major role in water, and PFOS, PFBA, and PFOA dominated the sediment samples in South Korea. The partition coefficients of PFASs were closely related to the fraction of organic carbon in the sediment and the carbon chain length of PFASs. Among the 15 compounds, the partition coefficients of 9 were significantly correlated with the fraction of organic carbon ( r >0.21, P <0.05), and the partition coefficient steadily increased with the increase of the carbon chain length. The results of ecological risk assessment suggested that the coastal urbanized areas of China and South Korea are still at a low risk. However, some specific areas also showed PFAS pollution. More attention should be paid to the potential health risks.

The sorption kinetics and isothermal sorption of polybrominated diphenyl ethers (PBDEs) by virgin and aged polyethylene (PE) and polystyrene (PS) microplastics with irradiation by ultraviolet light were studied, with 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) as a representative compound. The influence of different environmental factors, including salinity and dissolved organic matter, on its sorption were analyzed. The virgin and aged microplastics were characterized by scanning electron microscopy, x-ray diffraction, and total reflection infrared spectroscopy. The different models of kinetics and sorption isotherm were used to fit the data, and the sorption mechanism of PBDEs by microplastics was analyzed. The results showed that the main sorption modes of virgin and aged PE were surface sorption and external liquid film diffusion. The virgin and aged PS presented the surface sorption. The sorption isotherm was consistent with the Freudlich model, indicating that the sorption of BDE-47 by microplastics was characterized by a multi-phase, multi-layer, and non-uniform sorption process. The equilibrium sorption capacities of BDE-47 on virgin PE, aged PE, virgin PS, and aged PS were 3.72, 3.76, 6.04, and 3.46 ng·g -1 , respectively. There was no obvious difference in equilibrium sorption capacity between the aged and virgin PE. However, the equilibrium sorption capacity for the aged PS was decreased by 42.38% compared with that of the virgin PS. The partition of the outer liquid membrane diffusion was the main mechanism affecting sorption of PBDEs by PE. Compared with the virgin PS, the increase in crystallinity and surface oxygen-containing functional groups led to a decrease in the equilibrium sorption capacity of PBDEs on the aged PS. The sorption of BDE-47 was not significantly influenced by salinity. However, dissolved organic matter exerted a negative effect on the sorption of BDE-47.

Sediment samples were collected from 11 typical sites in Hengshui Lake separately in August 2018 and March 2019. Characteristics and ecological risk assessment of typical persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs), in these sediments were analyzed. The results showed that the average content of ΣPAHs in sediments of Hengshui Lake was 875.49 ng·g -1 and 1010.17 ng·g -1 in August 2018 and March 2019, respectively. Compared with other regions in China and abroad, ΣPAHs in sediments from Hengshui Lake were at moderate pollution level. Distribution of ΣPAHs varied between different sites, but the values changed within a narrow range in different seasons. Sources of PAHs in sediments from Hengshui Lake were complex, but combustion of wood and coal was the main source, followed by oil pollution. Generally, the ecological risk of PAHs was at a low level. However, fluorene pollution control should be strengthened. For ΣOCPs, the average values in sediments were 35.57 ng·g -1 and 38.39 ng·g -1 in August and March, respectively. Compared with other regions, the pollution of ΣOCPs was at a moderate level. In addition, the distribution of ΣOCPs varied a small amount between different sites. There were significant differences between the two seasons. The contents of DDTs in sediments were mainly related to the residual DDTs after long-term soil weathering and the input of recent DDTs sources. Contents of HCHs in sediments were influenced by the use of HCHs in industrial history and inputs of agricultural lindane. Generally, the ecological risk of OCPs was at a medium level, but the DDTs pollution control should be strengthened. For ΣPBDEs, the average values were 1.77 ng·g -1 and 1.45 ng·g -1 in the sediments in August 2018 and March 2019, respectively. Compared with other regions, they were at a lower pollution level. The distribution of ΣPBDEs showed small differences between different sites, and did not obviously vary between spring and summer. The PBDEs in sediments were mainly low-bromine PBDEs, which might be contaminated with penta-BDEs from textiles and foams. Additionally, PBDEs were also probably input by distant settlement and migration from the atmosphere, and soil flushing into the lake. PBDEs posed no immediate ecological risk.

To investigate the distribution, source, and ecological risk of organochlorine pesticides (OCPs) residues in Lake Gucheng, surface water, sediment, and biological samples were collected from 12 sampling sites of Lake Gucheng and its inlets and outlets during summer and winter, and the concentrations of 19 OCPs were analyzed. The results showed that the concentration (dry weight) of OCPs in Lake Gucheng ranged from 26.74 to 48.12 ng·L -1 in surface water, 9.01 to 35.34 ng·g -1 in sediment, and 13.39 to 124.29 ng·g -1 in organisms. The pollution characteristics of OCPs in surface water showed that the concentration was much higher in summer than in winter, and much higher at inflow and outflow rivers than in farming ponds and the central region of Lake Gucheng; the seasonal pollution characteristics in sediment were not obvious. All 19 kinds of OCPs in water, sediment, and organisms were detected in different degrees, and the dominant contaminants were HCHs and DDTs. α -HCH was the main pollutant at all sites in both surface water and sediment, with 21% to 42% of total HCHs in two seasons. p,p '-DDD was the main pollutant in surface water with 30% to 76% of total DDTs, whereas p,p '-DDT was the main pollutant in sediment with 68% to 93% of total DDTs in two seasons. Source analysis based on ratios of HCHs isomers and DDTs isomers indicated that there was a new input of OCPs under anaerobic conditions in the study area. The ecological risk assessment showed that the OCPs in surface water did not lead to significant health risks, but the OCPs in sediments might pose ecological risks to the Lake Gucheng ecosystem. The organisms were within the acceptable potential carcinogenic risk range.

An analytical approach was developed to simultaneously determine 13 antibiotics in sulfonamides, quinolones, and macrolides in leafy vegetables by ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-MS/MS). After optimizing extracted solutions, purification methods, and eluents of antibiotics in vegetable substrates, and taking into account the influence of environmental changes and experimental conditions on the results, the optimal experimental scheme was determined. This involved ①weighing 500 mg of vegetable samples and adding 20 mL of methanol-Mcllvaine-Na 2 EDTA solution; ② conducting ultrasonic and centrifugal extraction three times; ③ Allowing rotary evaporation to 20 mL to pass a HLB solid phase extraction column; ④ Eluting the extraction column using 6 mL of methanol, upon which the eluent was dried almost completely; ⑤ Re-dissolving the eluent with a mixed solution of acetonitrile:water (volume ratio of 2:8); ⑥ Detecting by UPLC-MS/MS after centrifugation and filtering. Phase A and B of UPLC-MS/MS used an aqueous solution of 1‰ formic acid and acetonitrile, respectively to conduct gradient elution. Results showed that when the pakchoi spiked at 300 ng·g -1 , the spiked recoveries of 13 antibiotics were 38.05%-96.97%. At 150 ng·g -1 , the spiked recoveries were 34.52%-111.10%. At 50 ng·g -1 , the recoveries of standard addition were 41.75%-107.13%, and the relative deviation (RSD) values were all below 8.68%. The detection limit was 0.4-1 ng·g -1 , and the limit of quantification was 1.5-3 ng·g -1 . This demonstrated good extraction and recovery efficiency on different types of leafy vegetables, and presented a good analytical application effect. The antibiotic residues were detected in four kinds of leafy vegetables in found in markets. The total content ranged from 1.59 ng·g -1 to 32.01 ng·g -1 , and the antibiotic content in samples was calculated by dry weight. The content of antibiotics in pakchoi was the highest, followed by Chinese cabbage, lettuce, and coriander. Among the antibiotics detected, sulfadimidine was the most abundant from the selected leafy vegetables. The content of antibiotics was very low, however the potential health risks caused by long-term consumption could not be ignored.

This study assesses the spatial distribution characteristics and ecological risk of phthalate esters (PAEs) in the surface sediments of the mainstream and tributaries of the Songhua River, China, using concentrations and composition of six PAEs, which were analyzed using gas chromatography-mass spectrometery (GC-MS). We assess the ∑ 6 PAEs ecological risk using the hazard quotient (HQ) method and environmental risk levels (ERL). The results were as follows. ① It was found that the total concentrations of ∑ 6 PAEs ranged from 6832.5 to 36298.9 ng·g -1 dry weight (average 18388.6 ng·g -1 ), with the main contributions coming from di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP). The difference between the main stream ∑ 6 PAEs (6832.5-36298.9 ng·g -1 , average 18616.9 ng·g -1 ) and the tributary ∑ 6 PAEs (10367.6-26593.3 ng·g -1 , average 18264.1 ng·g -1 ) was not significant ( P >0.05). The mean concentrations of individual PAEs in the tributary stream differed little from that of the main stream. The ∑ 6 PAEs concentration of the Songhua River decreased initially but then increased from the upstream to the downstream. The average ∑ 6 PAEs concentration in natural agricultural areas (18677.5 ng·g -1 ) was similar to that found in urban industrial areas (18063.7 ng·g -1 ), and DBP and DEHP contributed 98% of ∑ 6 PAEs. ② The main sources of ∑ 6 PAEs were domestic, agricultural production, and industrial production using plasticizers. ③ The ecological risk assessment indicated that DMP and BBP in the surface sediments of the Songhua River did not pose an ecological risk for aquatic organisms, and that DEP was associated with a low ecological risk, whereas DEHP and DBP posed a high ecological risk for aquatic organisms.

The Shen-Fu region is an important urban area in northeast China. We report on a study of the distribution of polybrominated diphenyl ethers (PBDEs) in representative topsoil from this region. In the summer of 2016, 72 soil samples from three cities (Shenyang, Fushun, and Shen-Fu New City) were collected, which covered four land use types:urban, rural residential, cultivated, and woodland. We report on the concentrations, compositions, and distributions of 14 PBDEs in soil and explore their sources, and additionally undertake human exposure analysis and health risk assessments. The results showed that the concentration of ∑ 14 PBDEs in the topsoil ranged from 0.279-50.719 ng·g -1 (dry weight), with a mean of (10.466±9.246) ng·g -1 . The concentrations of PBDEs was ranked for the cities as:Fushun > Shenyang > Shen-Fu New City > background, and for different land use types as:urban land > rural residential land > cultivated land > forest. Deca-PBDE had the highest proportion of all congeners, accounting for 81.25%-89.23% of all PBDEs. Source analysis indicated that commercial Deca-PBDE was the main source, contributing 66.06% of the total Deca-PBDE according to principal component analysis/multiple linear regression (PCA-MLR). Among five different age groups assessed for exposure, children in Fushun had the highest exposure dose:(20.98±25.01) ng·(kg·d) -1 . In terms of different land types, the highest exposure dose was for children living in urban areas:(18.54±20.27) ng·(kg·d) -1 . The non-oncogenic health risks in the Shen-Fu region are of a relatively low level.

To study the pollution characteristics and exposure health risk of perfluoroalkyl substances (PFASs) in road dust, 12 PFASs were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) in this study. PFAS concentrations in road dust ranged from 0.95 to 111 ng·g -1 , with an average concentration of (25.6±37.2) ng·g -1 , suggesting large spatial differences between PFASs in road dust. PFAS concentrations on the main roads were significantly higher than on minor roads, and the minor roads downtown displayed higher concentration levels than suburban minor roads. Perfluorobutanoic acid (PFBA) was the predominant compound in Section 1 of Jie-fang Road, Jin-niu-ba Road and Shui-nian-he Road, while perfluroroocantanoic acid (PFOA, 24.8%) and perfluorooctane sulfonate (PFOS, 24.1%) were the main PFASs on other roads, indicating different sources of PFASs in these areas. The total daily dose of PFASs in road dust for children and adults were 0.168 ng·(kg·d) -1 and 0.028 ng·(kg·d) -1 , respectively, suggesting higher exposure risk for children than adults. Therefore, more attention should be paid to children's health risk assessment. Daily doses of PFOA and PFOS in road dust for Chengdu residents were lower than the maximum daily intakes recommended by the European Authority, indicating that there was no immediate health risk to local residents.

Steroid hormones have been continuously detected and well studied in freshwater bodies in recent years, although information regarding their contamination characteristics in seawater is rare. In this paper, samples were collected in Liusha Bay, South China Sea, and the contamination characteristics, as well as the spatial distribution of 33 steroid hormones, were studied by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that 7 steroid hormones occurred with concentrations ranging from 0.003 (medroxyprogesterone, MP) to 9.023 ng·L -1 (dehydroprogesterone, DGT), and from 0.017 (androsta-1,4-diene-3,17-dione, ADD) to 9.281 ng·g -1 (4-androstene-3,17-dione, AED) in seawater and sediment samples, respectively. The concentrations of detected steroid hormones were higher during wet weather than during the dry weather, and higher in the aquaculture area compared to that in the non-aquaculture area. There were no significant differences in the spatial and temporal distribution of steroid hormones in sediment. Wastewater discharge and additives in aquaculture feeds were the main routes of steroid hormones entering the marine environment. The results of the ecological risk assessment indicated that the AED posed low risk to the marine environment, whereas other steroid hormones posed no risk. Correlation analysis indicated that the concentration distribution of steroid hormones was related to salinity, water temperature, particulate matter (SS), and chemical oxygen demand (COD) in the marine environment. The results of this study contribute to the understanding of the contamination characteristics of steroid hormones in the Liusha Bay area and provide a scientific basis for ecological risk assessment and control.

In order to study the effects of atmospheric transport and the wet/dry deposition on the content and distribution of organophosphate esters (OPEs) in remote areas, seven types of OPEs including tri-n-butyl phosphate (TnBP), tri (2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), tridichloropropyl phosphate (TDCPP), triphenyl phosphate (TPhP), tributoxyethyl phosphate (TBEP), and tris (2-ethylhexyl) phosphate (TEHP) were analyzed in plants and snow samples in Hailuogou using gas chromatography-mass spectrometry. The results showed that the pollution levels of the seven OPEs (∑7OPEs) in the plant samples ranged from 43.1 ng·g -1 to 1050.8 ng·g -1 . TBEP and TPhP were the main pollutants, accounting for 36%-70% and 24%-80% of the ∑7OPEs, respectively. The main pollutants in the snow in Hailuogou were the same as those in the plants, with TBEP dominating the profile of the ∑7OPEs at 47%, followed by TPhP at 24%. The analysis results of the grid analysis display system (Grads), backward trajectory model, and historical wind data of Hailuogou indicate that the OPEs in this region are affected mainly by atmospheric transmission from Chengdu and the junction of Yunnan Zhaotong and Yibin, Luzhou, and Xichang. The environment of Hailuogou has obviously been disturbed by human activities. It is necessary to conduct thorough investigations of its environmental behavior and to strengthen urban pollution control measures.

The external pollution of Dianchi Lake has been effectively controlled with the implementation of the integrated water environment control project. However, further attention should be paid to endogenous pollutants, such as surface sediments. To investigate the distribution of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Dianchi Lake, PAH concentrations in 19 surface sediment samples (collected in December 2016) were quantitatively measured by gas chromatography-mass spectrometry (GC-MS). The spatial and temporal distribution, sources, and ecological risks were also analyzed. The concentration of total PAHs (TPAHs) in the Dianchi Lake surface sediments varied in the range of 92.31-1546.78 ng·g -1 with an average of 496.30 ng·g -1 . The average concentration of TPAHs in the surface sediments from Caohai (932.37 ng·g -1 ) was much greater than that from Waihai (380.02 ng·g -1 ). With the implement of the integrated water environment control project, the concentration of TPAHs in the surface sediments from Dianchi Lake was significantly lower than those detected in 2012, and was already relatively low level among other key waterbodies in China. The PAH with the highest concentration was fluoranthene (80.65 ng·g -1 ) and the substance with the highest toxic equivalent quantity (TEQ) was dibenz[a, h] anthracene (42.97 ng·g -1 ). The PAHs were mainly composed of 4 ring and 5-6 ring compounds (with the concentration ratio of 40.38% and 40.22%, respectively), which indicated that the proportions of middle-ring and high-ring compounds were generally consistent. The results of the molecular diagnostic ratio analysis showed that the primary source of PAHs in Dianchi Lake surface sediments are biomass and coal combustion. Based on the potential ecological risk marker comparison method, the entire lake was classified as having a low ecological risk, while the ecological risk of Caohai was relatively higher, which should be concerned further. The results provide initial data and act as an important reference for the conservation and improvement of water quality in Dianchi Lake.