Fuchsman P C, Barber T R, Sheehan P J
McLaren/Hart-ChemRisk, 5900 Landerbrook Drive, Cleveland, Ohio 44124, USA.
Arch Environ Contam Toxicol. 1998 Nov;35(4):573-9. doi: 10.1007/s002449900418.
Hexachlorobenzene (HCB) is a hydrophobic organic chemical that has shown a lack of toxicity in aquatic tests at concentrations up to and exceeding the solubility limit. The equilibrium partitioning approach to deriving sediment quality benchmarks, which assumes that toxicity can be predicted based on contaminant concentrations in interstitial water, predicts that HCB will not produce direct toxicity to benthic invertebrates as a sediment contaminant. However, the potential for toxicity due to direct exposure to sediment-adsorbed HCB has not been thoroughly established. This study evaluated the survival and growth of the estuarine amphipod Leptocheirus plumulosus, the freshwater amphipod Hyalella azteca, and the midge Chironomus tentans (freshwater) following 10-day exposure to sediment spiked with a range of HCB concentrations. H. azteca was tested under both freshwater and estuarine (10 ppt salinity) conditions. No significant toxicity was observed for any test species at the highest test concentration (60 mg/kg normalized to 1% organic carbon). Minimum detectable differences were less than or equal to 20% for three of eight test endpoints. The observed results add to the available weight of evidence indicating a limited potential for HCB-related sediment toxicity to benthic invertebrates.
六氯苯（HCB）是一种疏水性有机化学品，在浓度达到并超过溶解度极限的水生试验中未表现出毒性。基于平衡分配法推导沉积物质量基准，该方法假定毒性可根据间隙水中的污染物浓度来预测，据此预测HCB作为沉积物污染物不会对底栖无脊椎动物产生直接毒性。然而，直接接触沉积物吸附的HCB所导致的潜在毒性尚未得到充分证实。本研究评估了河口双足虾Leptocheirus plumulosus、淡水双足虾Hyalella azteca以及摇蚊Chironomus tentans（淡水）在暴露于添加了一系列HCB浓度的沉积物10天后的存活和生长情况。H. azteca在淡水和河口（盐度为10 ppt）条件下均进行了测试。在最高测试浓度（以1%有机碳归一化后为60 mg/kg）下，未观察到任何测试物种有显著毒性。八个测试终点中的三个，其最小可检测差异小于或等于20%。观察结果进一步补充了现有证据，表明HCB相关沉积物对底栖无脊椎动物产生毒性的可能性有限。
