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Between 1945 and 1983, China was the world's largest producer of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), and the second largest producer of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs). The provinces of Liaoning, Hebei, Tianjin, Shandong, and Jiangsu around the Yellow and Bohai Seas have a long history of production and usage of OCPs and PCBs. To investigate their residual concentration, distribution, risk level, and temporal degradation, 7 OCPs and 7 indicator PCBs were determined in surface soils collected around the Yellow and Bohai Seas. Residues of the 7 OCPs and 7 PCBs were in the range of 5.89–179.96 ng g −1 dry weight (dw) and non-detectable (ND)–385.67 ng g −1 dw, respectively. Tianjin and Hebei provinces recorded the highest concentrations of OCPs and PCBs, respectively. Moreover, OCPs residues had a significant relationship with agriculture and orchard land-use types, whereas PCBs residues occurred more in wasteland. Lifetime carcinogenic and non-carcinogenic risks of OCPs and PCBs through ingestion, inhalation, and dermal contact indicated that OCPs and PCBs residues in surface soils are at a low risk level. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl acids (PFAAs) are being increasingly reported as emerging contaminants in riverine and marine settings. This study investigated the contamination level and spatial distribution of 17 PFAAs within the depth profile of the Bohai and Yellow Seas using newly detected sampling data from 49 sites (June 29 to July 14, 2016). Moreover, the riverine flux of 11 selected PFAAs in 33 rivers draining into the Bohai and Yellow Seas was estimated from previous studies (2002–2014) in order to establish the relationship between riverine sources and marine sinks. The results showed that the Bohai and Yellow Seas were commonly contaminated with PFAAs: total concentrations of PFAAs in the surface, middle, and bottom zones ranged from 4.55 to 556 ng L −1 , 4.61–575 ng L −1 , and 4.94–572 ng L −1 , respectively. The predominant compounds were PFOA (0.55–449 ng L −1 ), PFBA (

With the shift of fluorine chemical industry from developed countries to China and increasing demand for fluorine chemical products, occurrence of perfluoroalkyl substances (PFASs) in production and application areas has attracted more attention. In this study, 153 soil samples were collected from 21 cities along the urbanizing coastal area of the Bohai and Yellow Seas. PFASs in this area were relatively higher, compared with other study areas. The concentrations ranged from 2.76 to 64.0 ng g −1 , and those in most sites were between 2.76 and 13.9 ng g −1 , with a predominance of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Among the 21 coastal cities, contaminations of PFASs in Zibo, Nantong and Binzhou were elevated, which was likely affected by local fluorine chemical plants, equipment manufacturing and chemical industry, respectively. The total emissions of PFOA and PFOS were similar, with amount of 4431 kg and 4335 kg, respectively. Atmospheric deposition was the largest source, accounting for 93.2% of total PFOA and 69.6% of PFOS, respectively. In addition, due to application of aqueous film-forming foams (AFFFs) and sulfluramid, disposal of sewage sludge and stacking of solid waste, emission of PFOA and PFOS to soil was 1617 kg, accounting for 9.29% of the whole China. In general, pollution in Jiangsu, Shandong and Tianjin was more serious than those in Liaoning and Hebei, which was consistent with industrialization level and size of industrial sectors emitting PFASs. [ABSTRACT FROM AUTHOR]

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are extremely persistent in the environment, and have the potential for long-range transport. The present study focused on the Daling River and its tributary, a larger river flowing into Liaodong Bay of the Bohai Sea. Recent studies have shown the elevated levels of PFOS and PFOA in the Daling River. Hence, the objective of this study was to investigate the seasonal changes, fate and transport modeling of PFOS and PFOA concentrations using one-dimensional DHI MIKE-11 river model. We designed three scenarios to assess the risk of PFOS and PFOA in surface water: the measured concentrations, constant maximum and the magnitude of a continuous constant load. The mean absolute errors divided by the mean of measured concentrations were 41–64% for PFOS and 29–36% for PFOA. The result indicated that PFOS and PFOA in the downstream of the Daling River would not reach a harmful level with the current load. The fluorochemical parks contributed an average of 44.57% of the total PFOS and 95.44% of the total PFOA flow that reached the estuary. The mass flow was observed as 1.74 kg y −1 for PFOS and 40.57 kg y −1 for PFOA to the Bohai Sea. These modeling results may be useful for monitoring the status and trends of emerging POPs and will help the determination of the risk to both humans and wildlife, in the estuarine and coastal areas of the Bohai Sea, China. [ABSTRACT FROM AUTHOR]

In this study, the concentration of lead ([Pb]) in the surface water, sediments, soils and muscles of carp and crab in the upstream and downstream coastal watersheds along the Northern Bohai and Yellow Seas (NBYS) in China was investigated and the risks of Pb were evaluated. The mean [Pb] in the downstream water (2.62 μg/L) and sediments [24.5 mg/kg, dry mass (dm)] was greater than the Chinese seawater quality standard for class I (1 μg/L) and the regional background soil concentration (11.5 mg Pb/kg, dm), respectively. Approximately 37 % of the soils, mainly from the upstream regions, had [Pb] greater than the regional background concentration of 21.4 mg/kg, dm. The sites with relatively large [Pb] in the water, sediments and soils were located in the coastal watersheds of Tangshan and Huludao. The large enrichment factors in the sediments (2.41) and soils (2.22) suggested that human activities influenced the soils and sediments in this region more than in the other regions. Relatively large [Pb] was found in the crabs that were obtained from the upstream reaches of the Shuanglong and Daliao Rivers and the downstream reaches of the Luanhe and Liugu Rivers. Most of the crabs from the upstream regions contained greater [Pb] than the permissible limit for human consumption [0.3 mg/kg, wet mass (wm)]. The risk indices of the water, carp and crabs for humans were 0.002, 0.01 and 0.006, respectively. Based on the bioaccumulation factors, biota-sediment accumulation factors (BSAFs) and human risk indices, it was concluded that the human risks associated with crab were lower than those of carp despite the greater accumulation of Pb by the crabs from the water and sediments. Finally, the [Pb] in the sediments was significantly correlated with the [Pb] in the soils, which indicated that the same sources of Pb were responsible for the [Pb] in the sediments and soils in the coastal watersheds of the NBYS in China. [ABSTRACT FROM AUTHOR]

The total concentrations of 16 United States Environmental Protection Agency (US EPA)-listed polycyclic aromatic hydrocarbons (PAHs) found in coastal and estuarine sediments along the northern shores of the Bohai and Yellow Seas, China, at any study location varied from 0.236 to 8.34 nM g−1dry weight (dw). For a given PAH, concentrations varied by one to two orders of magnitude. Ecological risk assessments based on biota–sediment accumulation factors (BSAFs) indicated that the potential ecological hazard of PAHs in the sediments was limited. The average total sediment PAH concentrations were less than the effects range low, indicating that PAHs currently present in the sediments were not harmful to aquatic organisms. The estimated PAH concentration in the aquatic organisms was 0.223 nM g−1and posed a limited threat to human health via biological concentration from sediment to harvest of the sea. Assuming no additional PAH inputs, 99% of the 16 PAH molecules currently present in the sediments would be degraded in 40 years. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water. [Copyright &y& Elsevier]

Highlights: [•] Significant contents of Arsenic, Copper and Zinc were found in water and sediment. [•] Arable land suffered the heaviest metal contamination among four different land uses. [•] Significant greater metals found in the Jie River indicated regional point sources. [•] Arsenic in water at 11 sites may cause deleterious effects on the residents’ health. [•] Metals in sediment of YT5 and YT6 and soil of CZ1 and CZ2 have high ecological risk. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbon (PAH) concentrations and their risks in surface sediments ( n = 35) collected from coastal and estuarine areas of the northern Bohai and Yellow Seas, China, were investigated in 2008. Total concentrations of PAHs ranged from 52.3 to 1,870.6 ng/g dry weight. The greatest concentrations were observed in the Dou River of Tangshan where waste water from small factories is discharged into the river without treatment. At other locations, municipal sewage was the primary contributor of PAHs. Regional differences in concentrations of PAHs in sediments are related to human activities. Concentrations of PAHs were significantly correlated with concentrations of organic carbon in sediments. The patterns of relative concentrations and types of PAHs observed and knowledge of the potential sources, as well as the results of a principal component analysis, are consistent with the primary sources of PAHs in sediments of the northern Bohai Sea and Yellow Sea, being derived from the high-temperature pyrolytic processes such as combustion of fossil fuel. While concentrations of PAHs at most locations did not exceed the effects range median stated by the numerical effect-based sediment quality guidelines of the United States, concentrations of PAHs at some locations were similar to or greater than the effects range low. [ABSTRACT FROM AUTHOR]

Abstract: The concentration of total mercury [Hg] in waters, sediments and biota (carp and crabs) as well as the concentration of methyl mercury [MeHg] in biota from upstream (surface water systems) and downstream (coastal and estuarine systems) areas within coastal watersheds along the Chinese Northern Bohai and Yellow Seas were investigated. In most waters tested, the [Hg] could have adverse effects on coastal wildlife. Based on the Chinese water quality standards for mercury, 67% of upstream waters cannot be used for agriculture or recreation. Furthermore, 53% of downstream waters cannot be used as harbors or for industrial development. The [Hg] in 3% of sediments from the Wuli and Luanhe Rivers were sufficient to cause adverse effects on ecosystems. The [Hg] in 41% of downstream crabs and the [MeHg] in 29% of downstream crabs were higher than the limits for human consumption set by the Chinese government. In all abiotic and biotic samples, only the downstream carp from the Northern Yellow Sea had a [Hg] or [MeHg] higher than those from the Northern Bohai Sea. Industrialization and urbanization were the primary sources of mercury contamination in the aquatic ecosystems studied. [Copyright &y& Elsevier]

Concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA) and other perfluorinated compounds (PFCs) were measured in water and sediment from coastal Bohai Bay and surrounding rivers flowing into the bay. Of the 15 PFCs measured, PFOS and PFOA were detected with the greatest frequency. Concentrations in water ranged from<0.2 to 31 ng·L-1 and<1.0 to 82 ng·L-1 for PFOS and PFOA, respectively. Concentrations of PFOS and PFOA in sediments ranged from<0.1 to 2.0 ng·g-1 dw and<0.1 to 0.5 ng·g-1 dw, respectively. Concentrations of PFCs in Bohai Bay were less than those observed in other areas in Asia, but greater concentrations of ∑PFCs were observed in the Dalin River with concentrations increasing from upstream to downstream, and the greatest concentrations in sediment were observed in tidal flats. The ratio of ∑PFCs in sediment and water indicated that sediment could serve as a significant sink for PFUnA. [ABSTRACT FROM AUTHOR]

A systematic survey of organochlorine pesticides (OCPs) including hexachlorocyclohexane isomers (α-HCH, β-HCH, γ-HCH, δ-HCH and ΣHCH) and dichlorodiphenyltrichloroethane metabolites (p,p'-DDT, p,p'-DDE, o,p'-DDT, p,p'-DDD and ∑DDT) in soils along the north coastal areas of the Bohai Sea, China, has been lacking. In this study, 31 representative surface soil samples were collected along the north coastal and riverine areas of the Bohai Sea to characterise the potential for adverse effects of ∑HCH, ∑DDT and their individual isomers and transformation products. Concentrations of ΣHCH and ΣDDT in soils ranged from less than the limit of detection (