Alternative antifouling biocides become less active in sediments?

从三苯基硼烷-吡啶(TPBP)与沉积物的动力学和其降解产物的生态毒性两个方面评价了新型防污化合物TPBP的环境归宿。苯酚和联苯在天然海水中的生物降解和在近紫外光照射下的光降解中检测到主要的降解产物。TPBP与沉积物的吸附取决于沉积物中有机质的含量，而不是从沉积物中解吸出来。TPBP与沉积物吸附生成苯酚和联苯。被检测的两种降解产物以及其他可能的产物，如苯、二苯基硼烷和单苯基硼烷的生态毒性远低于TPBP。TPBP在自然环境中的去向估计如下：从船底涂料中释放出来的TPBP与悬浮固体结合，最终落入沉积物中。TPBP在上层水柱中会被部分光降解，但在海底有机质含量较低的沉积物中降解较少，这可能会对底栖生物产生不利影响。测试细菌直接接触自然沉积物，使用一种改进的方法来插补沉积物的浊度和颜色对生物化学发光的影响。根据沉积物湿重，用EC50法对S所采集的三个海湾沉积物的污染状况进行了定量评价。大内湾没有检测到毒性，前鲁湾的一些样品有中等毒性，大阪湾的几个沉积物有高度毒性。毒性与底泥中有机质含量有关。需要进行更多的研究，以调查观察到的毒性与防污剂和其他有毒化学品的持久性之间的关系。

Environmental fate of the new antifouling compound, triphenylborane-pyridine (TPBP), was evaluated in terms of its kinetics with sediments and ecotoxicity of its degradation products. Phenol and biphenyl was detected as major degradation products via biodegradation with natural seawater and via photodegradation with near ultra-violet irradiation. TPBP was adsorbed with sediment depending on organic matter contents of sediments and was not desorbed from the sediments. TPBP adsorbed with sediments produced phenol and biphenyl. Ecotoxicity of the two degradation products detected and other putative products such as benzene, diphenylborane, and monophenylborane was much lower than one of TPBP. The fate of TPBP in natural environment was estimated as follows: TPBP released from ship bottom paint is incorporated with suspended solids and finally fall into sediments. TPBP will be partly photodegraded in upper water column but may be less degraded in sediments with less organic matter contents at sea bottom, this may lead possible adverse effects on benthic organisms.A toxicity kit, TOX Screen 2 using Photobacterium leiognathi SB, was applied for sediment toxicity evaluation. Test bacteria was directly exposed to natural sediments using an improved method to interpolate the effects by turbidity and color of sediment on biochemiluminescence. Pollution of the sediment s collected in three bays were quantitatively evaluated with EC50 based on wet weight of sediments. No toxicity was detected in Othuchi Bay, moderate toxicity was detected in some specimen from Maizuru Bay, and high toxicity was bind in several sediments from Osaka Bay. The toxicity was dependent on the organic matter contents of sediments. More research is needed to investigate how the toxicity observed was related with the persistence of antifouling biocides and other toxic chemicals.