Delorenzo M E, Keller J M, Arthur C D, Finnegan M C, Harper H E, Winder V L, Zdankiewicz D L
National Oceanic and Atmospheric Administration, National Ocean Service, 219 Fort Johnson Rd., Charleston, SC 29412, USA. marie.delorenzo@ noaa.gov
Environ Toxicol. 2008 Apr;23(2):224-32. doi: 10.1002/tox.20327.
Triclosan, a commonly used antimicrobial compound, has been measured in aquatic systems worldwide. This study exposed marine species to triclosan to examine effects primarily on survival and to investigate the formation of the degradation product, methyl-triclosan, in the estuarine environment. Acute toxicity was assessed using the bacterium Vibrio fischeri, the phytoplankton species Dunaliella tertiolecta, and three life stages of the grass shrimp Palaemonetes pugio. P. pugio larvae were more sensitive to triclosan than adult shrimp or embryos. Acute aqueous toxicity values (96 h LC50) were 305 microg/L for adult shrimp, 154 microg/L for larvae, and 651 microg/L for embryos. The presence of sediment decreased triclosan toxicity in adult shrimp (24 h LC50s were 620 microg/L with sediment, and 482 microg/L without sediment). The bacterium was more sensitive to triclosan than the grass shrimp, with a 15 min aqueous IC50 value of 53 microg/L and a 15 min spiked sediment IC50 value of 616 microg/kg. The phytoplankton species was the most sensitive species tested, with a 96 h EC50 value of 3.55 microg/L. Adult grass shrimp were found to accumulate methyl-triclosan after a 14-day exposure to 100 microg/L triclosan, indicating formation of this metabolite in a seawater environment and its potential to bioaccumulate in higher organisms. Triclosan was detected in limited surface water sampling of Charleston Harbor, SC at a maximum concentration of 0.001 microg/L, substantially lower than the determined toxicity values. These findings suggest triclosan poses low acute toxicity risk to estuarine organisms; however, the potential for chronic, sublethal, and metabolite effects should be investigated.
三氯生是一种常用的抗菌化合物，已在全球范围内的水生系统中被检测到。本研究将海洋物种暴露于三氯生中，主要考察其对生存的影响，并研究在河口环境中降解产物甲基三氯生的形成。使用费氏弧菌、浮游植物杜氏盐藻以及草虾帕氏长臂虾的三个生命阶段评估急性毒性。帕氏长臂虾幼体对三氯生比成年虾或胚胎更敏感。成年虾的急性水体毒性值（96小时半数致死浓度）为305微克/升，幼体为154微克/升，胚胎为651微克/升。沉积物的存在降低了成年虾对三氯生的毒性（24小时半数致死浓度：有沉积物时为620微克/升，无沉积物时为482微克/升）。该细菌对三氯生比草虾更敏感，水体中15分钟半数抑制浓度值为53微克/升，加标沉积物中15分钟半数抑制浓度值为616微克/千克。浮游植物是所测试的最敏感物种，96小时半数有效浓度值为3.55微克/升。成年草虾在暴露于100微克/升三氯生14天后被发现积累了甲基三氯生，表明在海水环境中形成了这种代谢物及其在高等生物中生物累积的潜力。在南卡罗来纳州查尔斯顿港的有限地表水采样中检测到三氯生，最大浓度为0.001微克/升，远低于所确定的毒性值。这些发现表明三氯生对河口生物构成的急性毒性风险较低；然而，应研究其慢性、亚致死和代谢物影响的可能性。
