Contamination Characteristics Of Halogenated Flame Retatdants In Surficial Soils And Sediments From Zhejiang Province, China

Halogenated flame retardants （HFRs） are applied to reduce the flammability ofmany consumer products such as electrical and electronic products （E&E）, textiles, andfurnishings. They have been industrial chemicals of growing worldwide environmentalconcern since1990s. HRFs are known to be harmful for the environment and humansbecause of their toxicity, bioaccumulation potential, and persistence in the environment,as well as their potential to be atmospherically transported from source regions towardremote regions. Soil and sediment are two major "sink" of organic pollutants. The levelsand distribution characteristics of HFRs in soil and sediment can indicate the pollutionstatus and main sources of such compounds in the region. This work investigated theconcentrations, distributions and influencing factors of dechlorane plus （DP） and itsanalogues （Dechloranes） and polybrominated diphenyl ethers （PBDEs） in surficial soilsfrom Zhejiang province and sediments from Qiantang River.The concentrations of DP, mirex, dechlorane602（Dec602）, and dechlorane603（Dec603） in surficial sediments from the Qiantang River were0.29ng/g dry weight（dw）（below method dectection limit （BDL）-1.08ng/g dw）,0.13ng/g dw （BDL-0.676ng/g dw）,0.012ng/g dw （BDL-0.048ng/g dw）, and0.003ng/g dw （BDL-0.026ng/gdw）, respectively. Dechlorane604（Dec604） was not detected in all sediment samples.The anti-DP fractional abundance （fanti） of sediment samples were above the mean ofcommercial DP. The concentrations of Σ7PBDEs （BDE28,47,99,100,153,154, and 183） and BDE209were0.701ng/g dw （0.067-5.28ng/g dw） and70.81ng/g dw（2.16-446.4ng/g dw）, respectively. BDE209was the predominant congener detectedamong the eight congeners, consistent with the fact that technical deca-BDE mixturesare lagerly used in China.The local urban and industrial activity was the primary source of HFRs in surficalsediments in the Qiantang River, which was supported by the fact that theconcentrations of HFRs in urban sites were greatly higher than that in countryside zone.An extreme high concentration of HFRs at reservoir site in countryside region indicatedthat the dam cound block the transportation of HFRs in the Qiantang River and madethe reservoir to be primary sink of HFRs. The specific hydrodynamic conditions ofQiantang River and organic matter played an important role in the distributions andtransportation of HFRs in sediments of Qiantang River.The concentrations of DP, mirex, Dec602, and Dec603in surficial soils from theZhejiang province were0.141ng/g dw （BDL-3.593ng/g dw）,0.059ng/g dw（BDL-4.927ng/g dw）,0.010ng/g dw （BDL-0.136ng/g dw）, and0.003ng/g dw（BDL-0.040ng/g dw）, respectively. Dec604was not detected in all soil samples. Theanti-DP fractional abundance (f_anti) of soil samples were also above the mean ofcommercial DP. The concentrations of Σ7PBDEs and BDE209were0.701ng/g dw（0.067-5.28ng/g dw） and70.81ng/g dw （2.16-446.4ng/g dw）, respectively. BDE209was the predominant congener detected among the eight congeners.The HRFs levels in soils were in the order of sites in electronic waste recyclingarea> urban area> farming area> forest area. Electronic waste recycling area andurban area might be two primary sources of HRFs in soils from Zhejiang province. Bothtypes and organic matter levels of soils did not significantly influence the distributionsof HFRs in soils from Zhejiang province.