Bettinetti R, Giarei C, Provini A
Università degli Studi di Milano, Biology Department, Ecology Section, Via Celoria 26, Milan, Italy.
Arch Environ Contam Toxicol. 2003 Jul;45(1):72-8. doi: 10.1007/s00244-002-0126-6.
This study consisted of a 10-day whole sediment toxicity test with the chironomid Chironomus riparius and a 28-day sediment toxicity test with the oligochaete Tubifex tubifex at seven sites to assess the quality of the River Lambro (Italy), one of the most contaminated rivers of the Po Basin. Endpoints measured were survival and growth for chironomids and cocoon deposition and development of young worms for tubificid oligochaetes. Responses were evaluated in relation to the occurence of organic micropollutants (PCBs, DDT, HCB, and HCH) representative of the industrial and agricultural contamination of the area. Though survival of the organisms remained unaffected, sublethal effects were observed at all sites. The sediment sampled at the farthest upstream site differed from the control only in the number of cocoons deposited by the worms. Both test species in the next three sediments, where concentrations of PCB and DDT were in the range 21.9-39.5 ng g(-1) DW and 0.6-1.3 ng g(-1) DW, respectively, experienced greater toxicity in terms of growth and reproduction. Contamination was particularly high in the site closest to Milan, where the river receives untreated urban and industrial discharges. Levels of total PCBs and total DDT here were up to two orders of magnitude higher than those found at the other sampling locations, and chironomid growth and the reproductive endpoints of tubificids were significantly lower than in the control and the other sites. The test results for the next two stations showed improvement relative to that of Milan, although contamination was still evident. Sublethal effects were in agreement with the measured concentrations of the principal persistent organic pollutants and should be included as part of environmental monitoring efforts as a basis for assessing the recovery of the river.
本研究包括在七个地点对摇蚊（Chironomus riparius）进行为期10天的全沉积物毒性试验，以及对颤蚓（Tubifex tubifex）进行为期28天的沉积物毒性试验，以评估兰布罗河（意大利）的水质，该河是波河流域污染最严重的河流之一。测量的终点指标是摇蚊的存活率和生长情况，以及颤蚓茧的沉积和幼体发育情况。根据该地区工农业污染的代表性有机微污染物（多氯联苯、滴滴涕、六氯苯和六氯环己烷）的出现情况评估响应。尽管生物的存活率未受影响，但在所有地点均观察到亚致死效应。在最上游地点采集的沉积物与对照相比，仅在蠕虫沉积的茧数量上有所不同。在接下来的三个沉积物中，两种受试物种分别处于多氯联苯浓度为21.9 - 39.5 ng g(-1)干重、滴滴涕浓度为0.6 - 1.3 ng g(-1)干重的环境中，在生长和繁殖方面表现出更大的毒性。在最靠近米兰的地点污染尤为严重，该河流接收未经处理的城市和工业排放物。此处的总多氯联苯和总滴滴涕水平比其他采样地点高出多达两个数量级，摇蚊的生长以及颤蚓的繁殖终点指标显著低于对照和其他地点。接下来两个站点的测试结果相对于米兰站点有所改善，尽管污染仍然明显。亚致死效应与主要持久性有机污染物的测量浓度一致，应作为环境监测工作的一部分纳入，作为评估河流恢复情况的依据。
