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Recently, China has commenced water quality criteria (WQC) research using the species sensitivity distribution (SSD) method. However, it is difficult to obtain sufficient toxicity data on native species for thousands of contaminants. In this study, the feasibility of deriving aquatic life criteria using toxicity data from non-native species was analyzed (taking the USA as an example). Firstly, 10 pollutants [As(Ⅲ), Cr(Ⅵ), Hg, Cu, Pb, Zn, nitrobenzene, parathion, chlorpyrifos, tributyltin] with plenty of toxicity data (at least 3 Phyla and 8 Families) both in China and the USA were selected based on the recommended aquatic life criteria of 58 pollutants by the US EPA. Secondly, the two-sample Kolmogorov-Smirnov (K-S) test and comparison method of important points of HC

Based on the determinations of total nitrogen (TN), organic matter (OM), carbon-nitrogen ratio (C/N), δ

In this study, toxicity data of aquatic species in Liaohe River for heavy metal chromium (VI) was collected and selected. The aquatic life criteria for chromium (VI) in Liaohe River was derived based on these toxicity data. Moreover, water samples of 25 sites in Liaohe River were collected, and the concentrations of chromium (VI) in these samples were analyzed. Finally, ecological risk assessment of chromium (VI) in Liaohe River was performed. Moreover, interspecies correlation estimation method (ICE) established by US EPA was used to predict the acute toxicity of species in Liaohe River, and aquatic life criteria based on predicted toxicity data was derived. The results showed that: the measured CMC (criteria maximum concentration), measured CCC (criteria continuous concentration) and the predicted CMC were 17. 73, 12. 15 and 13. 97 µg . L -1, respectively. Therefore, the ICE method could be used to predict the aquatic life criteria, because the predicted criteria value was very similar to the measured criteria value. Analysis of chromium (V) showed that the chromium (VI) concentrations of the 25 sites in Liaohe River were all below Class I or Class II water quality standards (GB 3838-2002), and the water quality was in good condition. However, for the potential risk of chromium (VI) exposure to the aquatic life of Liaohe River, the result of ecological risk assessment showed that chromium (V) concentrations in 7 sites exceeded the CCC in July, and chromium (VI) concentrations in 6 sites exceeded the CCC in December. Therefore, unacceptable effect on aquatic species caused by chromium (VI) exposure might have occurred in some sites of Liaohe River.

The acute toxicity (48 h-LC50 ) of copper to Daphnia magna predicted by the biotic ligand model (BLM) was compared with the 48 h-LC50 measured in water samples from Liaohe River and Taihu Lake at four specific sites in wet and dry seasons. The results showed that 48 h-LC50 values predicted by BLM were 232.75-411.49 microgL-1 and 48 h-LC50 values measured in the water samples were 134. 55-350. 00 microg L-1 in three sites of Hongmiaozi of Liaohe River, Pingtaishan and Tuoshan of Taihu Lake, which had a better consistency. While for Tongjiangkou of Liaohe River, there was a difference between the BLM predictions and the measured values in wet and dry seasons. According to the predictions and the experimental results, water effect ratios (WERs) were in the range of 2. 18-5.79 and 1.88-11.15 which all were higher than 1. The acute toxicity of Cu of all sites in dry season was greater than those in wet season, which might be that Cu complexation with dissolved organic matter (DOC) reduced the toxicity of Cu.

Tissue distribution and bioconcentration factors of tetrabromobisphenol A (TBBPA) in five economic fishes in Chaohu Lake were measured with SPE-HPLC. The results showed that, the average concentration of TBBPA was 4.70-11.20 ng x g(-1) (dry weight) in these fishes, in an order as White fishSilver CarpBighead CarpCommon CarpLongsnout Catfish. The highest concentration of TBBPA was found in the kidney, followed by liver and gill. The concentrations in fat and muscle were very low. Silver carp was really different from the other four fishes with the highest measured level in liver, followed by kidney and gills. In addition, the TBBPA concentration in tissues of the white fish showed positive correlation with the fish weight, especially in liver and kidney, but the trend is not significant in the back and belly tissues. The bioaccumulation factors of TBBPA for the 5 fishes were 9.56-22.64 based on the average concentration of TBBPA in water (0.52 microg x L(-1)) detected in this study, indicating insignificant bioconcentration effects of TBBPA on five fishes in Chaohu Lake.