Study of Species Sensitivity Distribution for Pollutants

Species sensitivity of different taxonomic groups from China and America for 8 priority pollutants including nitrobenzene, 2,4,6-trichlorophenol, 2,4-dichlorophenol, parathion, As(III), Cr(VI), Hg, and Cd was compared. The results showed that there was no significant difference between Chinese and American taxa. Results from species sensitivity distribution (SSD) curves of vertebrates and invertebrates for heavy metals including Cu, Hg, Cd, Cr(VI), Pb, and Zn showed that invertebrate taxa were more sensitive to each heavy metal than vertebrates. Copper was the most toxic to vertebrate, followed by Hg, Cd, Zn, and Cr(VI). The hazardous concentrations for 5 % of the species affected (HC5) were derived to determine the criteria value. The HC5 values of the six heavy metals were sorted in the following order: Zn > Pb > C r > Cd > Hg > Cu, indicating their toxicities in opposite order. Gene expression effect toxicity data of three metals were also analyzed to decide the rank of species sensitivity. The results showed that different metals may have different order for acute, chronic, and gene effect data. Besides, the interspecies correlation estimation (ICE) model can use the initial toxicity estimate for one species to produce correlated toxicity values for multiple species. The ICE model can usually be utilized to develop SSD and HC5. The results from phenanthrene and benzo[a]pyrene (BaP) showed that the ICE model was verified as a valid approach for generating SSDs with limited toxicity data to derive WQC for phenanthrene benzo[a]pyrene (BaP) and possibly other toxicants if applicable.