Talapatra S N, Banerjee S K
Department of Environmental Science, Calcutta University College of Science, 35 Ballygunge Circular Road, Kolkata 700 019, India.
Food Chem Toxicol. 2007 Feb;45(2):210-5. doi: 10.1016/j.fct.2006.07.022. Epub 2006 Aug 30.
Determination of genotoxic effect in fish, micronucleus test as well as the study of the abnormal shape of nuclei is a suitable measure, in which the presence or absence of genotoxins can be detected in water. In the present study, micronuclei and abnormal nuclei frequencies were scored in the gill and kidney erythrocytes of the fish Labeo bata grown in the sewage-fed fish farms of East Calcutta wetlands. Three experimental sites were chosen, namely, Bantala, Chowbaga and Chingrihata (basically these sites have sewage-fed fishponds), which were compared with fishponds of no sewage influence as the control area. Highly significant differences (P<0.001) were noticed for micronucleus frequencies in the gill and kidney erythrocytes of experimental fishes, where kidney erythrocytes showed an increased value than gill erythrocytes without any statistical differences. The frequencies of nuclear abnormalities such as necrotic cells, apoptotic cells, notch nucleated cells and binucleated cells were also counted separately for gill and kidney erythrocytes, in which significantly (P<0.001, P<0.01, P<0.05) increased values were obtained in comparison to control populations. These genotoxicity results confirmed that the sewage-fed ponds contain genotoxic metals such as Cr, Zn, Cu, Pb, Mn, Fe through wastewater and sludge because of the direct use of sewage water without pretreatment which may lead to health risks among humans through chronic consumption of fish from these experimental fish ponds. Other vertebrates grown in sewage-fed ponds may also suffer a certain amount of genotoxic substances.
测定鱼类的遗传毒性效应、微核试验以及细胞核异常形态的研究是一种合适的方法，通过该方法可以检测水中是否存在遗传毒素。在本研究中，对生长在东加尔各答湿地污水养殖鱼塘中的巴氏野鲮鱼鳃和肾红细胞中的微核和异常核频率进行了评分。选择了三个实验地点，即班塔拉、乔巴加和清格里哈塔（这些地点主要有污水养殖鱼塘），并与无污水影响的鱼塘作为对照区域进行比较。实验鱼鳃和肾红细胞中的微核频率存在极显著差异（P<0.001），其中肾红细胞的值高于鳃红细胞，但无统计学差异。还分别对鳃和肾红细胞中坏死细胞、凋亡细胞、缺口核细胞和双核细胞等核异常频率进行了计数，与对照群体相比，这些频率显著（P<0.001、P<0.01、P<0.05）增加。这些遗传毒性结果证实，由于未经预处理直接使用污水，污水养殖池塘通过废水和污泥含有铬、锌、铜、铅、锰、铁等遗传毒性金属物质，长期食用这些实验鱼塘的鱼可能会给人类带来健康风险。在污水养殖池塘中生长的其他脊椎动物也可能受到一定量的遗传毒性物质影响。
