Fate and ecotoxicity of new antifouling compounds in aquatic environments.

本研究的目的是为替代有机锡的新型防污化合物制定管理策略。使用的化合物是Irgarol 1051、敌草隆、KH 101、吡硫锌、吡硫铜和海九211。1)日本水环境污染三种化合物的最高浓度分别为：伊加洛尔1051为0.30μg/L，M1为1.9μg/L，敌草隆为3.1μg/L。2)降解研究汞离子能催化伊加洛尔在水中的水解生成M1。太阳辐射还降解水中的伊加洛尔，生成M1。水中天然成分加快了伊加洛尔的光解速率，表明腐植酸类物质对伊加洛尔具有光敏降解作用。在水中检测到的Irgarol、M1和敌草隆的来源被确定为日本MARKET提供的商业防污涂料。3)生态毒性研究使用与环境相关的生物，如海洋细菌、微藻、海藻、浮萍、浮游动物和陆地植物，评估了Irgarol和M1的生态毒性。用生态毒理学数据和残留浓度对其环境风险进行了评价。用幼鱼、悬浮培养的鱼类细胞、海胆受精卵和非靶标植物对几种新的防污化合物进行了毒性评价。金属吡硫酮对供试物种的毒性较高，尤其是吡硫锌对海胆卵发育的抑制作用达每升毫微克。UV-A灯照射下的金属吡硫酮对海胆的毒性随光照时间的延长而降低。这表明金属吡硫酮类化合物可以被太阳辐射降解。

The aim of this study was to establish management strategy for the new antifouling compounds alternative to organotins. Compounds used were Irgarol 1051, Diuron, KH 101, Zinc pirithione, Copper Pyrithione, and Sea-Nine 211. Conclusions obtained were as follows :1) Pollution of Japanese aquatic environmentThe highest concentrations of three compounds detected in Japanese ambient waters were as follows ; 0.30 μg/L for Irgarol 1051, 1.9 μg/L for M1, and 3.1 μg/L for Diuron. Three-year survey at two stations indicated the concentrations in higher order as Diuron > Irgarol 1051 > M1, generally.2) Degradation studyMercuric ion could catalyze hydrolysis of Irgarol in water to produce M1. Solar irradiation also degraded Irgarol in water to produce M1. Photodegradation rate of Irgarol was accelerated by natural components in water, suggesting photosensitive degradation with humic substances. The origin of Irgarol, M1, and Diuron detected in water was ascertained to commercial antifouling paints available in Japanese market.3) Ecotoxicity studyEcotoxicity of Irgarol and M1 was evaluated using environmentally relevant organisms such as marine bacteria, microalgae, seaweed, duckweed, zooplankton, and terrestrial plants. The environmental risk of them was assessed with both the ecotoxicological data and residue concentrations. Toxicity of several new antifouling compounds were evaluated using juvenile fish, suspension-cultured fish cells, fertilized egg of sea urchin, and non-target plant species. The toxicity of metal pyrithiones was high to those species tested, especially zinc pyrithione inhibited sea urchin egg development at femtgram per liter. The metal pyrithiones irradiated with UV-A lamp decreased its toxicity to sea urchin, depending on the duration of light treatment. This suggested that metal pyrithiones could be degraded by solar irradiation.