Matozzo Valerio, Tomei Andrea, Marin Maria Gabriella
Department of Biology, University of Padova, 35131 Padova, Italy.
Mar Pollut Bull. 2005 Dec;50(12):1686-93. doi: 10.1016/j.marpolbul.2005.07.011. Epub 2005 Aug 22.
Measurement of acetylcholinesterase (AChE) is widely used as a biomarker of exposure to neurotoxic compounds in aquatic environments. In the present study, AChE activity was monitored in the clam Tapes philippinarum in the Lagoon of Venice, with the aim of evaluating the possible exposure of animals to neurotoxic compounds. Two sampling strategies were followed. In the first case, temporal and spatial variations of AChE activity were measured in clams collected seasonally (from October 2003 to June 2004) in 3 sites of the Lagoon: Campalto (site 1), near a sewage treatment plant, Marghera (site 2), a highly polluted area, and Poveglia (site 3), a reference site. The condition index (CI) of clams was also calculated. In the second case, AChE activity was measured in clams collected at the end of seasonal samplings in 12 sites located throughout the Lagoon: areas licensed for clam farming (sites 5 to 11), nearby canals characterised by waste waters from agricultural areas (sites 4, 12, 13, 14), and a reference site outside the Lagoon (site 15). Results revealed a significant reduction in AChE activity in clams from Marghera in October, January and April, indicating their probable exposure to neurotoxic compounds originating in the industrial zone of Porto Marghera. A seasonal trend in AChE activity was also observed, enzyme activity being higher in January and lower in June. Clams from Campalto generally had higher CI values than those from Marghera and Poveglia. However, no particular correlation between AChE activity and CI was found. Lastly, marked differences in AChE activity were recorded when comparing enzyme activity of clams from various sites in the Lagoon of Venice with those of clams collected at site 15. Significant reductions in AChE activity were observed in animals collected in both nearby canals and licensed areas, indicating the homogeneous spatial distribution of potentially neurotoxic compounds throughout the Lagoon. It is probable that sediment mobilisation caused by clam harvesting and the passage of shipping plays an important role in resuspension of persistent contaminants having neurotoxic activity.
乙酰胆碱酯酶（AChE）的测量被广泛用作水生环境中神经毒性化合物暴露的生物标志物。在本研究中，对威尼斯潟湖中的菲律宾蛤仔的AChE活性进行了监测，目的是评估动物可能接触神经毒性化合物的情况。采用了两种采样策略。第一种情况是，在潟湖的3个地点（坎帕尔托（地点1），靠近污水处理厂；马尔盖拉（地点2），一个污染严重的地区；波韦利亚（地点3），一个参考地点）季节性采集（从2003年10月至2004年6月）的蛤仔中测量AChE活性的时间和空间变化。还计算了蛤仔的条件指数（CI）。第二种情况是，在整个潟湖的12个地点季节性采样结束时采集的蛤仔中测量AChE活性：蛤仔养殖许可区域（地点5至11）、附近有来自农业区废水的运河（地点4、12、13、14）以及潟湖外的一个参考地点（地点15）。结果显示，10月、1月和4月马尔盖拉的蛤仔中AChE活性显著降低，表明它们可能接触了源自马尔盖拉港工业区的神经毒性化合物。还观察到AChE活性的季节性趋势，酶活性在1月较高，6月较低。坎帕尔托的蛤仔的CI值通常高于马尔盖拉和波韦利亚的蛤仔。然而，未发现AChE活性与CI之间有特定相关性。最后，将威尼斯潟湖不同地点的蛤仔的酶活性与在地点15采集的蛤仔的酶活性进行比较时，记录到AChE活性存在显著差异。在附近运河和许可区域采集的动物中观察到AChE活性显著降低，表明整个潟湖潜在神经毒性化合物的空间分布均匀。蛤仔捕捞和船舶通行引起的沉积物移动可能在具有神经毒性活性的持久性污染物的再悬浮中起重要作用。
