Distribution, health risk assessment, and water quality criteria of phthalate esters in Poyang Lake, China

Although China has been the main manufacturer and consumer of phthalate esters (PAEs), human health ambient water quality criteria (AWQCs) have not been proposed for these chemicals. In this study, the distribution and bioaccumulation of six PAEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), bis (2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DnOP)) were investigated in 11 edible fish species collected from Poyang Lake, China. The results showed that the total concentrations of the six PAEs in the fish ranged between 118.63 and 819.84 mu g/kg wet weight (mean of 327.50 +/- 190.44 mu g/kg). DMP, DEP, DBP, and DEHP were detected in all samples, of which DEHP and DBP were two of the most predominant phthalates, accounting for more than 90% of the total PAEs. The DEHP concentrations in fish with different habitat preferences were different, demersal species were significantly higher than pelagic species (p < 0.05). The mean natural logarithmic bioaccumulation factors (log BAFs) of PAEs increased with increasing lipophilicity of the substances, which yielded the following regression equation: log BAF (L/kg) = 0.103 log K-ow + 2.158 (r(2) = 0.940, p < 0.05, n = 4). Using this quantitative structure-activity relationship to calculate BAFs for the remaining undetected substances (BBP and DnOP) to derive AWQCs. According to the natural parameters, the human health AWQCs relating to PAE concentrations for water and fish consumption were derived as 9.4 x 10(3) (DMP), 5.0 x 10(2) (DEP), 4.2 x 10(1) (DBP), 1.1 (BBP), 8.6 x 10(- 2) (DEHP), and 2.0 (DnOP) mu g/L. Human health risk assessment indicated that the dietary intake of DEHP may exert a carcinogenic effect on residents of the Poyang Lake region. The results provide important input to assess the health risk posed by PAEs contaminated surface water.