Highlight the Important Role of Proteins in Bioaccumulation and Biomagnification of Pfass in Aquatic Organisms Based on Comparison with Opes

Abstract

Despite the wide acceptance that bioaccumulation and biomagnification of per/polyfluoroalkyl substances (PFASs) is related to proteins in organisms, few evidences are available. Here, bioaccumulation and biomagnification of 9 organophosphate esters (OPEs) and 16 PFASs, which have similar range of log Kow (octanol-water partitioning coefficient) values, were compared in Taihu Lake, China. ∑OPEs level in water (150 - 23036 ng/L) was significantly higher than ∑PFASs (57.3 - 351 ng/L). Although the logarithm of bioaccumulation factors of both OPEs and PFASs in biofilm positively correlated with their log Kow, the slope of PFASs was 4 times of that of OPEs, due to the strong interactions of PFASs with biofilm extracellular proteins. Additionally, PFASs exhibited distinctly greater biomagnification factors from biofilm to snails (3.09 - 17.8) than OPEs (0.39 - 3.48). Significant correlations between the concentrations and protein contents in snails were observed for most long-chain PFASs, but not for any OPEs. All these results verified that proteins played crucial roles in bioaccumulation and biomagnification of PFASs. Multiple receptor models identified polyurethane foam (77.9%) and food packaging/metal plating (56.9%) were the primary sources of OPEs and PFASs in Taihu Lake, respectively. We provided strong evidences that proteins facilitated bioaccumulation and biomagnification of PFASs.

Keywords: OPEs, PFASs, biofilm, bioaccumulation, biomagnification, protein