Department of Environmental Technologies, Centro Andaluz de Ciencia y Tecnología Marinas (CACYTMAR), Universidad de Cádiz, Campus Río San Pedro, Cádiz, Spain.
Sci Total Environ. 2010 Mar 15;408(8):1779-85. doi: 10.1016/j.scitotenv.2010.01.029. Epub 2010 Feb 11.
Industrial wastes have a substantial impact on coastal environments. Therefore, to evaluate the impact of cooling water discharges from coastal power plants, we studied the kinetics of the degradative processes and the ecotoxicity of two antifouling products: (1) a classic antifouling product; sodium hypochlorite (NaClO) and (2) an alternative one; aliphatic amines (commercial under the registered trade mark Mexel432). To assess the persistence of both compounds the decay of sodium hypochlorite and the primary biodegradation rate of Mexel432 were determined in natural seawater at 20 degrees C. The results indicated a more rapid decay of NaClO than Mexel432. The degradation behavior of both chemicals was described following a logistic model, which permitted calculating kinetic parameters such as t(50) or t(90). The t(50) was 1h and 2d for NaClO and Mexel432, respectively. To evaluate the potential risks of the aforementioned treatments to marine organisms, the acute toxicity of both antifouling products was studied on the microalgae Isochrysis galbana and Dunaliella salina, and on the invertebrate Brachionus plicatilis, using growth inhibition and death tests as toxic response, respectively. For I. galbana, the 96-h EC(50) values were 2.91+/-0.15mg/L of NaClO and 4.55+/-0.11mg/L of Mexel432. D. salina showed values of 96-h EC(50) of 1.73+/-0.16mg/L of NaClO and 7.21+/-0.1mg/L of Mexel432. Brachionus plicatilis showed a 24-h LC(50) of 1.23+/-0.1mg/L of NaClO and 3.62+/-0.37mg/L of Mexel432. Acute toxicity was highly dependent on the chemical and species tested. NaClO presented more toxic effects than Mexel432, also B. plicatilis was the most sensitive species in both cases. The lowest NOECs obtained, 0.25mg/L for NaClO and 2.12mg/L for Mexel432, were similar to the theoretical residual concentrations of these biocides in cooling water discharges. Therefore, these discharges can cause undesirable negative effects upon the aquatic organisms present.
工业废物对沿海环境有重大影响。因此，为了评估沿海电厂冷却水排放对环境的影响，我们研究了两种防污产品的降解动力学和生态毒性：（1）经典的防污产品；次氯酸钠（NaClO）和（2）一种替代产品；脂肪胺（商业上以注册商标 Mexel432 销售）。为了评估这两种化合物的持久性，在 20°C 的天然海水中测定了次氯酸钠的衰减和 Mexel432 的初级生物降解速率。结果表明，NaClO 的衰减速度快于 Mexel432。这两种化学品的降解行为符合逻辑模型，通过该模型可以计算出 t（50）或 t（90）等动力学参数。NaClO 和 Mexel432 的 t（50）分别为 1h 和 2d。为了评估上述处理方法对海洋生物的潜在风险，我们使用生长抑制和死亡测试分别研究了这两种防污产品对微藻小球藻和杜氏盐藻以及无脊椎动物褶皱臂尾轮虫的急性毒性。对于小球藻，96hEC（50）值分别为 2.91+/-0.15mg/L 的 NaClO 和 4.55+/-0.11mg/L 的 Mexel432。杜氏盐藻的 96hEC（50）值分别为 1.73+/-0.16mg/L 的 NaClO 和 7.21+/-0.1mg/L 的 Mexel432。褶皱臂尾轮虫的 24hLC（50）值分别为 1.23+/-0.1mg/L 的 NaClO 和 3.62+/-0.37mg/L 的 Mexel432。急性毒性高度取决于所测试的化学物质和物种。NaClO 的毒性作用大于 Mexel432，同时褶皱臂尾轮虫在这两种情况下都是最敏感的物种。获得的最低 NOEC 值，0.25mg/L 的 NaClO 和 2.12mg/L 的 Mexel432，与这些杀生剂在冷却水中的理论残留浓度相似。因此，这些排放物可能对存在的水生生物造成不良的负面影响。
