Finnegan Meaghean C, Pittman Sherry, DeLorenzo Marie E
Graduate Program in Marine Biology, College of Charleston, 205 Fort Johnson Rd., Charleston, SC 29412, USA.
Arch Environ Contam Toxicol. 2009 Jan;56(1):85-95. doi: 10.1007/s00244-008-9166-x. Epub 2008 May 6.
Irgarol 1051 is an algistatic compound used in copper-based antifoulant paints. It is a widespread and persistent pollutant of the estuarine environment. Ilyanassa obsoleta, the Eastern mud snail, is a common intertidal gastropod that inhabits mud flats and salt marshes along the east coast of North America. It is an important inhabitant of the estuarine environment; contributing to nutrient regeneration and regulating microbial processes in the sediments. The toxicity of irgarol to estuarine gastropods has not been previously examined, although they have the potential to be exposed to antifoulants through both aqueous and sediment routes. The objectives of this study were to evaluate irgarol's effects on I. obsoleta survival, reproductive status (imposex occurrence and testosterone levels), chemoreceptive function, and cellular respiration (cytochrome-c oxidase activity). Irgarol was moderately toxic to I. obsoleta; adult aqueous 96-h LC(50) = 3.73 mg/L, larval aqueous 96-h LC(50) = 3.16 mg/L, and adult sediment 10-day LC(50) = 12.21 mg/kg. Larval snails were not significantly more sensitive to irgarol than adult snails. A chronic 45-day aqueous irgarol exposure (0.005-2.5 mg/L) did not induce imposex or affect free-testosterone levels. The 45-day chronic LC(50 )of 1.88 mg/L was significantly lower than the 96-h acute value. A 96-h acute aqueous irgarol exposure (0.375-1.5 mg/L) caused a decrease in normal response to chemosensory cues such as the presence of food or predators. There was a significant increase in cytochrome-c oxidase activity at 2.5 mg/L, which might indicate irgarol's disruption of the mitochondrial membrane and subsequently ATP synthesis. Although the toxicity values determined for I. obsoleta exceeded irgarol concentrations measured in surface waters, results from this toxicity assessment will provide valuable information to environmental resource managers faced with decisions regarding the use and regulation of antifoulant paints in the coastal zone.
灭藻醌1051是一种用于铜基防污涂料的抑藻化合物。它是河口环境中一种广泛存在且持久的污染物。东方泥螺（Ilyanassa obsoleta）是一种常见的潮间带腹足纲动物，栖息于北美东海岸的泥滩和盐沼。它是河口环境的重要栖息者，有助于养分再生并调节沉积物中的微生物过程。尽管河口腹足纲动物有可能通过水体和沉积物途径接触到防污剂，但此前尚未研究过灭藻醌对它们的毒性。本研究的目的是评估灭藻醌对东方泥螺的生存、生殖状态（性畸变发生率和睾酮水平）、化学感受功能以及细胞呼吸（细胞色素c氧化酶活性）的影响。灭藻醌对东方泥螺具有中等毒性；成体在水体中的96小时半数致死浓度（LC50）= 3.73毫克/升，幼体在水体中的96小时半数致死浓度（LC50）= 3.16毫克/升，成体在沉积物中的10天半数致死浓度（LC50）= 12.21毫克/千克。幼体蜗牛对灭藻醌的敏感性并不显著高于成体蜗牛。为期45天的灭藻醌水体慢性暴露（0.005 - 2.5毫克/升）未诱导性畸变或影响游离睾酮水平。45天的慢性半数致死浓度（LC50）为1.88毫克/升，显著低于96小时急性值。为期96小时的灭藻醌急性水体暴露（0.375 - 1.5毫克/升）导致对食物或捕食者等化学感应线索的正常反应降低。在2.5毫克/升时细胞色素c氧化酶活性显著增加，这可能表明灭藻醌破坏了线粒体膜并随后影响了ATP合成。尽管测定的东方泥螺毒性值超过了地表水中测得的灭藻醌浓度，但该毒性评估结果将为面临沿海地区防污涂料使用和监管决策的环境资源管理者提供有价值的信息。
