Brominated and organophosphate flame retardants along a sediment transect encompassing the Guiyu, China e-waste recycling zone

Huiru Li; Mark J La Guardia; Hehuan Liu; Robert C Hale; T Matteson Mainor; Ellen Harvey; Guoying Sheng; Jiamo Fu; Ping'an Peng

doi:10.1016/j.scitotenv.2018.07.276

Brominated and organophosphate flame retardants along a sediment transect encompassing the Guiyu, China e-waste recycling zone

Sci Total Environ. 2019 Jan 1:646:58-67. doi: 10.1016/j.scitotenv.2018.07.276. Epub 2018 Jul 20.

Authors

Huiru Li¹, Mark J La Guardia², Hehuan Liu³, Robert C Hale⁴, T Matteson Mainor², Ellen Harvey², Guoying Sheng¹, Jiamo Fu¹, Ping'an Peng³

Affiliations

¹ State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
² Department of Aquatic Health Sciences, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, VA 23062, United States.
³ State Key Laboratory of Organic Geochemistry, Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
⁴ Department of Aquatic Health Sciences, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, VA 23062, United States. Electronic address: hale@vims.edu.

PMID: 30048869
DOI: 10.1016/j.scitotenv.2018.07.276

Abstract

e-Waste recycling using crude techniques releases a complex, yet incompletely characterized mixture of hazardous materials, including flame retardants (FRs), to the environment. Their migration downstream and the associated risks also remain undocumented. We examined 26 FRs (18 brominated (BFRs: 12 polybrominated diphenyl ether (PBDE) congeners, plus 6 alternatives) and 8 organophosphate esters (OPEs)) in surficial sediments of the Lian River. Sampling encompassed the river's origin, through the Guiyu e-waste recycling zone, to its mouth, as well as associated tributaries. OPE exceeded BFR concentrations in most sediments, despite their far greater water solubilities. Among OPEs, tris(1-chloro-2-propyl) phosphate dominated upstream, but shifted to triphenyl phosphate in Guiyu and downstream sediments. For PBDEs, Deca-BDE dominated upstream, but Penta-BDE prevailed in Guiyu and at many downstream sites. Among emerging alternative BFRs, decabromodiphenyl ethane dominated upstream, transitioning to 1,2-bis(2,4,6,-tribromophenoxy)ethane in Guiyu sediments. Penta-BDE (BDE-47 + -99, 668-204,000 ng g^-1, ∑PBDEs 2280-287,000 ng g^-1), tetrabromobisphenol A (2,720-41,200 ng g^-1), 1,2-bis(2,4,6,-tribromophenoxy)ethane (222-9870 ng g^-1) and triphenyl phosphate (4260-1,710,000 ng g^-1, OPEs 6010-2,120,000 ng g^-1) concentrations in Guiyu sediments were among the highest reported in the world to date. The continuing dominance of these e-waste indicative FRs in sediments downstream of Guiyu suggested that FR migration from Guiyu occurred. Hazard quotients >1.0 indicated that the extreme sediment concentrations of individual FRs posed ecological risks in most Guiyu reach and downstream areas. Simultaneous exposure to multiple FRs likely increased risks. However, risks may be mediated if FRs were associated with strong sorbents, e.g. carbon black from burned debris, hydrophobic polymer fragments, or resided as additives within polymer fragments.

Keywords: Circuit board; Flame retardants; Polymer additive; Risk characterization; Source attribution.