Polybrominated Diphenyl Ethers In China Research Articles

Health risk assessment and development of human health ambient water quality criteria for PBDEs in China

Polybrominated diphenyl ethers (PBDEs) are not only a class of highly efficient brominated flame retardants (BFRs) but also a class of typical persistent organic pollutants (POPs) that are persistent and widely distributed in various environmental media. This study examined the concentrations of PBDEs in five environmental media (water, soil, air, dust, and food) and two human body media (human milk and blood) in China from 2010 to 2020. In addition, this study conducted multi-pathway exposure health risk assessments of populations of different ages in urban, rural, key regions, and industrial factories using the Monte-Carlo simulation. Finally, the human health ambient water quality criteria (AWQC) of eight PBDEs were derived using Chinese exposure parameters and bioaccumulation factors (BAFs). The results showed that the eastern and southeastern coastal regions of China were heavily polluted by PBDEs, and the variation trends of the ΣPBDEs concentrations in the different exposure media were not consistent. PBDEs did not pose a risk to urban and rural residents in ordinary regions, but the hazard indexes (HIs) for residents in key regions and occupational workers exceeded the safety threshold. Dust exposure was the primary exposure pathway for urban and rural residents in ordinary regions, but for residents in key regions and occupational workers, dietary exposure was the primary exposure pathway. BDE-209 was found to be the most serious individual PBDE congener in China. The following human health AWQC values of the PBDEs were derived: drinking water exposure: 0.233–65.2 μg·L−1; and drinking water and aquatic products exposure: 8.51 × 10−4–1.10 μg·L−1.

Characteristics of halogenated flame retardants in the atmosphere of Dalian, China

Samples of gas and fine particulate matter (PM2.5) were collected in Dalian, China, a typical coastal city, to determine the concentrations, seasonal variations, influential factors, sources, and gas-PM2.5 partitioning of polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and dechlorane plus (DPs) in the ambient air. Annual average concentrations of Σ7PBDEs, BDE209, Σ6NBFRs, and DPs were 4.40 ± 2.93, 1460 ± 2500, 7.81 ± 6.85, and 0.15 ± 0.14 pg/m3 for the gas phase, and 2.68 ± 1.64, 4291 ± 4306, 13.6 ± 23.4, and 0.31 ± 0.22 pg/m3 for the fine particle phase, respectively. BDE209 was the dominant congener, followed by HBB and BEH-TEBP, and seasonal variations in air concentrations were apparent for BFRs, especially those in the gas phase. Moreover, meteorological parameters and criteria air pollutants revealed significant positive correlations between temperature and less-brominated BFRs in the gas phase, and between PM2.5 and highly-brominated BFRs in the particle phase. This suggests that the presence of these compounds in ambient air may largely result from combustion-related processes. Furthermore, an analysis of the gas-PM2.5 partitioning of BFRs and DPs suggested that BFRs and DPs mostly attained equilibrium, except for some NBFRs. Due to the ban of commercial penta-, octa-, and deca-BDEs by the Stockholm Convention, emissions from historical use and combustion are becoming the important sources of PBDEs in China.

Multiple-life-stage probabilistic risk assessment for the exposure of Chinese population to PBDEs and risk managements

Studies assessing body burden of polybrominated diphenyl ethers (PBDEs) exposure have been conducted in the United States and Europe. However, the long-term assessment that is associated with multimedia exposure of PBDEs for the Chinese population is not available. The current study estimated the health risks using large PBDEs data to quantify the contributions of various media from different regions and distinguished the most vulnerable periods in life. We summarized media-specific (soil, dust, outdoor and indoor air, human milk and food) concentration of PBDEs in China from 2005 to 2016. Probabilistic risk assessment was adopted to estimate the health risks of infants, toddlers, children, teenagers and adults through ingestion, inhalation and dermal absorption. Monte Carlo simulation and sensitivity analysis were performed to quantify risk estimates uncertainties. E-waste areas had the highest PBDEs concentration, which was at least an order of magnitude higher than in other areas. BDE209 was the primary congener, accounting for 38–99% of the estimated daily intake. The dominant exposure pathway for infants was dietary intake through human milk, whereas dust ingestion was a higher contributing factor for toddlers, children, teenagers and adults. The 95th percentile of hazard index for infants and toddlers from e-waste areas of Guangdong and Zhejiang provinces exceeded one. Our estimates also suggested that infants may have the highest body burdens of PBDEs compared to other age groups. Sensitivity analyses indicated that PBDEs concentrations and ingestion rates contributed to major variances in the risk model. In this study, e-waste was found as a significant source of PBDEs, and PBDEs-containing e-waste are likely to be a threat to human health especially during early period of life. Risk strategies for better managing environmental PBDEs-exposure and human health are needed, due to the high intake of PBDEs and their persistence in the environment.

Deriving aquatic life criteria for PBDEs in China and comparison of species sensitivity distribution with TBBPA and HBCD

Polybrominated diphenyl ethers (PBDEs) are important industrial brominated flame retardants. PBDEs have raised great concerns for their persistence, bioaccumulation, and harm to aquatic life and human health. Pentabromodiphenyl ether (PeBDE), octabromodiphenyl ether (OcBDE), and decabromodiphenyl ether (DeBDE) are three main commercial PBDEs congeners. In this study, published ecotoxicity data of these three PBDEs congeners for Chinese freshwater species were collected, and several acute and chronic toxicity tests for the three PBDEs congeners were performed. Using the derivation method for aquatic life criteria developed by the United States Environmental Protection Agency (USEPA), we determined that the criterion maximum concentration (CMC) for PeBDE, OcBDE and DeBDE for protection of freshwater organisms were 0.0492 mg/L, 0.197 mg/L and 0.239 mg/L, respectively. The criterion continuous concentration (CCC) for PeBDE, OcBDE and DeBDE were 0.0103 mg/L, 0.0224 mg/L and 0.0267 mg/L, respectively. The results provided a good reference for the derivation of PBDEs' water quality criteria and a basis for ecological risk assessment of PBDEs. In addition, the results of species sensitivity distribution comparison showed that the toxicity rank of five brominated flame retardants was TBBPA > PeBDE > OcBDE > DeBDE > HBCD.

Time trends of polybrominated diphenyl ethers in East China Seas: Response to the booming of PBDE pollution industry in China

The East China Seas (ECSs) are the receptors of the land-based persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs) mainly from China through atmospheric deposition driven by the East Asian winter monsoon and fluvial discharge (e.g., Yangtze River and Yellow River), making the offshore sediments to be a good proxy to reconstruct history of those pollutants in China. In this work, four well-placed sediment cores were extracted from the mud areas in the ECSs, and the 210Pb-dated cores were analyzed to yield historical concentration profiles of PBDEs in the area. The results showed that there was a persistent increase from 1970s and almost no clear sign in the decline of PBDEs until recently in China. More importantly, there was a faster increase of PBDEs from 1990s in China; while this period was just shown as gradually leveling off or even declining trends in developed countries. The persistently increasing trend of PBDEs in China since 1990s could be largely due to the booming of the manufacturing industry and unexpectedly transfer of PBDE pollution from developed countries to China. Besides, the relative high concentrations and fluxes of PBDEs in the core from coastal ECS located near a well-known electrical/electronic waste (e-waste) recycling area suggests an important contribution of PBDE emissions from recycling centers of e-waste in China. Although efforts in environmental monitoring of PBDE contamination have been substantially increased over the last decade, China is still lagging behind in terms of nationwide regulation of PBDE usage and treatment of disposal PBDE-containing products.

Brominated flame retardants in Chinese air before and after the phase out of polybrominated diphenyl ethers

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

Polybrominated Diphenyl Ethers (PBDEs) and Indicator Polychlorinated Biphenyls (PCBs) in Foods from China: Levels, Dietary Intake, and Risk Assessment

A national survey of polybrominated diphenyl ethers (PBDEs) and indicator polychlorinated biphenyls (PCBs) congeners in various foodstuffs from the Chinese total diet study (TDS) performed in 2007 was conducted for the first time. Meats and aquatic foods had the highest average sum PBDEs (192.5 and 190.6 pg g⁻¹ fresh weight, respectively). For indicator PCBs, the highest average concentration was found in aquatic foods (628.7 pg g⁻¹ fresh weight). On the basis of measured PBDE and indicator PCB levels, the dietary intake estimate was subsequently calculated for the nonoccupationally exposed population in China. For adults, average estimated dietary intakes of PBDEs and indicator PCBs were 0.76 and 2.34 ng kg⁻¹ bw day⁻¹, respectively. Health risk assessment of PBDEs using a MOE approach recommended by EFSA suggested unlikely health concern with respect to current dietary intake of PBDEs in China.

Temporal trends of brominated flame retardants in coastal waters of Japan and South China: Retrospective monitoring study using archived samples from es-Bank, Ehime University, Japan

The present paper is a summary of studies conducted at the Center for Marine Environmental Studies, Ehime University, on temporal trends of brominated flame retardants (BFRs) in coastal waters of Japan and South China. Archived marine mammal fat tissues and dated sediment cores were used to evaluate temporal trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in relation to their usage in the region. The results indicate that environmental concentrations of these BFRs in Japan and South China increased significantly during the last several decades. Temporal trends in the contaminant concentrations were consistent with historical consumption of the corresponding BFRs. PBDE levels in marine mammals and sediments from Japan, after showing peak concentrations in the 1990s, appear to be leveling off in recent years, in accordance with the discontinued usage of Tetra- and Octa-BDEs in Japan from the 1990s. The change in concentration levels was also accompanied by changes in PBDE congener profiles, i.e. shift towards increased proportion of higher brominated BDEs. Furthermore, in recent years HBCD concentrations in marine mammals from Japan appear to exceed those of PBDEs, presumably reflecting increasing usage of HBCDs over PBDEs. In finless porpoises from the South China Sea, PBDE levels were much higher than HBCD concentrations both in the past and recent years, implying consumption of HBCDs was not as high as that of PBDEs in China. In dated sediment cores from Tokyo Bay, concentrations increased exponentially with doubling times of 4.6–7.9 years, 6.1–12 years and 7.1–12 years for BDE-209, ΣPBDEs and HBCDs, respectively.