Gao Hongxia, Cao Yanhua, Liu Yingli, Liu Nan, Guan Weijun
North China University of Science and Technology, Tangshan, China.
Environ Sci Pollut Res Int. 2017 Mar;24(8):7051-7059. doi: 10.1007/s11356-016-8354-x. Epub 2017 Jan 16.
The purpose of this study was to explore genotoxicity due to organic pollutants in wastewater-irrigated vegetables using biological and chemical analyses. Chinese cabbages from wastewater-irrigated farmland were taken as the research object. For the in vitro test, DNA damage was characterized in rat hepatocytes exposed to organic extracts from the cabbages using the comet assay. For the in vivo tests, mice were exposed to organic extracts from the cabbages. DNA damage was assessed in mouse peripheral blood lymphocytes (PBLs), and chromosome damage was assessed in bone marrow cells using the comet assay and micronucleus test, respectively. For the chemical analysis, gas chromatography-mass spectrometry (GC/MS) was used to analyze the organic compounds in the organic vegetable extracts. The in vitro test results showed that the comet tail lengths of the DNA in rat hepatocytes were significantly increased in the group dosed with 0.36 g/ml (P < 0.05), and the comet tailing rates of the hepatocytes were significantly increased in the groups dosed with 0.24 and 0.36 g/ml (P < 0.05). The in vivo test results indicated that the comet tail lengths of the DNA in mouse PBLs were increased in the low- and high-dose groups and that the comet tailing rate of the PBLs was increased in the high-dose group (P < 0.05). The chemical analysis results showed that the total organic content in the organic vegetable extracts from the wastewater-irrigated area (1.355 mg/kg) was significantly higher than the content in the cabbage samples from the clean-water-irrigated area (0.089 mg/kg). This finding indicated that wastewater irrigation can cause organic pollution with genetic toxicity in vegetables. This study also showed that in vivo and in vitro biological tests can reflect the joint toxicity of organic pollutants, and the test results were in accordance with the chemical analysis of the organic pollutant compositions.
本研究旨在通过生物学和化学分析，探究污水灌溉蔬菜中有机污染物的遗传毒性。以污水灌溉农田的大白菜作为研究对象。体外试验中，采用彗星试验对暴露于大白菜有机提取物的大鼠肝细胞中的DNA损伤进行表征。体内试验中，让小鼠暴露于大白菜有机提取物。分别采用彗星试验和微核试验评估小鼠外周血淋巴细胞（PBL）中的DNA损伤以及骨髓细胞中的染色体损伤。化学分析方面，采用气相色谱 - 质谱联用（GC/MS）分析有机蔬菜提取物中的有机化合物。体外试验结果显示，给予0.36 g/ml剂量组大鼠肝细胞DNA的彗星尾长显著增加（P < 0.05），给予0.24和0.36 g/ml剂量组的肝细胞彗星拖尾率显著增加（P < 0.05）。体内试验结果表明，低剂量组和高剂量组小鼠PBL中DNA的彗星尾长增加，高剂量组PBL的彗星拖尾率增加（P < 0.05）。化学分析结果表明，污水灌溉区有机蔬菜提取物中的总有机含量（1.355 mg/kg）显著高于清水灌溉区白菜样品中的含量（0.089 mg/kg）。这一发现表明污水灌溉会导致蔬菜产生具有遗传毒性的有机污染。本研究还表明，体内和体外生物学试验能够反映有机污染物的联合毒性，且试验结果与有机污染物成分的化学分析结果一致。
