【摘要】 有机磷酸酯(OPEs)作为一种新型的阻燃剂和增塑剂,在环境中普遍存在,尤其在土壤中常被检出,因此其环境和健康风险亟待评估。为探究OPEs对土壤生物的毒性效应,选取磷酸三正丁酯(TnBP)作为受试物,以赤子爱胜蚓(Eisenia fetida)为指示生物,采用人工土壤法研究不同浓度TnBP对蚯蚓生长、抗氧化酶系统、乙酰胆碱酯酶(AChE)活性、体腔细胞DNA损伤及8-羟基脱氧鸟苷(8-OHdG)含量的影响。结果表明,TnBP暴露对蚯蚓生长无明显抑制作用,但TnBP胁迫可引起蚯蚓体内抗氧化酶活性增强,脂质过氧化产物丙二醛含量显著上升,表明蚯蚓受到氧化损伤;彗星试验结果显示,彗尾DNA含量和Olive尾矩均显著上升,表明TnBP暴露能够引起蚯蚓体腔细胞DNA损伤; 8-OHdG含量也显著增加,其水平与暴露浓度存在明显的剂量-效应关系,提示TnBP暴露可引起蚯蚓体腔细胞氧化性DNA损伤; AChE活性受到的影响则较为微弱。综上,本研究阐明了TnBP暴露对蚯蚓的毒性效应并为进一步研究OPEs对土壤的生态风险评估提供科学依据。更多还原

【Abstract】 As a group of emerging flame retardants and plasticizers,organophosphate esters （OPEs） are ubiquitous in the environment,especially in soil,therefore,their environmental and health risks need to be assessed urgently.To evaluate the potential toxicity of OPEs to soil ecosystem,we investigated the effects of different concentrations of tri-n-butyl phosphate （TnBP） on earthworms （Eisenia fetida） in artificial soil. The growth rate,activities of antioxidase system and acetylcholinesterase （AChE）,levels of malondialdehyde （MDA）,DNA damage as well as its products 8-hydroxydeoxyguanosine （8-OHdG） content were measured after exposure to 0,0.1,and 1 mg·kg^-1 TnBP in the artificial soil for 3,7,and 14 days. The results showed that 14-day exposure of TnBP did not significantly inhibit the growth of E. fetida,while the antioxidant enzymes activity and MDA content significantly increased,indicating that TnBP could induce oxidative damage in earthworm. Comet assay showed that both the tail DNA content and the Olive tail moment values in all treated groups were significantly higher than those in the control group. Furthermore,the presence of TnBP also induced the increase of 8-OHdG and exhibited a concentration-related response,suggesting that TnBP-induced DNA damage might be attributed to oxidative DNA lesions. The impacts of TnBP on AChE activity were relatively weak. In conclusion,this study demonstrated that TnBP had biochemical toxicity on earthworms,which sheds light on the toxicological effects of TnBP on earthworms and provides a scientific basis for further study of OPEs on soil ecological risk assessment.更多还原