Priority and emerging flame retardants in rivers: Occurrence in water and sediment, Daphnia magna toxicity and risk assessment

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• 作者：Joyce Cristale ; Alej ; ro Garc¨ªa V¨¢zquez ; Carlos Barata ; Silvia Lacorte
• 关键词：PBDE ; New brominated flame retardants ; Organophosphate flame retardant ; D. magna toxicity ; Risk assessment ; River
• 刊名：Environment International
• 出版年：2013
• 出版时间：September, 2013
• 年：2013
• 卷：59
• 期：Complete
• 页码：232-243
• 全文大小：1083 K

文摘

The occurrence, partitioning and risk of eight polybrominated diphenyl ethers (PBDEs), nine new brominated (NBFRs) and ten organophosphorus flame retardants (OPFRs) were evaluated in three Spanish rivers suffering different anthropogenic pressures (Nal¨®n, Arga and Bes¨°s). OPFRs were ubiquitous contaminants in water (¦²OPFRs ranging from 0.0076 to 7.2 ¦Ìg L^? 1) and sediments (¦²OPFRs ranging 3.8 to 824 ¦Ìg kg^? 1). Brominated flame retardants were not detected in waters, whereas ¦²PBDEs ranged from 88 to 812 ¦Ìg kg^? 1 and decabromodiphenyl ethane (DBDPE) reached 435 ¦Ìg kg^? 1 in sediments from the River Bes¨°s, the most impacted river. The occurrence of flame retardants in river water and sediment was clearly associated with human activities, since the highest levels occurred near urban and industrial zones and after wastewater treatment plants discharge. Daphnia magna toxicity was carried out for OPFRs, the most ubiquitous flame retardants, considering individual compounds and mixtures. Toxicity of nine tested OPFRs differed largely among compounds, with EC₅₀ values ranging over three magnitude orders (0.31-381 mg L^? 1). Results evidenced that these compounds act by non-polar narcosis, since their toxicity was proportional to their lipophilicity (K_ow). Furthermore, their joint toxicity was additive, which means that single and joint toxicity can be predicted knowing their concentration levels in water using quantitative structure activity relationships (QSARs) and predictive mixture models. Based on these results, a risk assessment considering joint effect was performed calculating and summing risk quotients (RQs) for the water and sediment samples. No significant risk to D. magna (¦²RQs < 1) was observed for any of the monitored rivers.