【作者】 刘斌；

【导师】 李光德；

【作者基本信息】 山东农业大学 ， 环境工程（专业学位）， 2021， 硕士

【摘要】 磷酸三(2-氯丙基)酯(Tris(2-chloroisopropyl)phosphate,TCPP)是一种有机磷酯类阻燃剂(Organophosphorus Flame Retardants,OPFRs),具有价格低、阻燃效果好等优点。作为一种新兴阻燃剂,其市场潜力巨大,生产和消耗量逐年上升,但其在环境中难以降解,目前在各种环境介质中均被检出,且在生物体内包括人体内也被检出,说明其可以通过食物链进行富集,危害人的生命健康。镉(Cadmium,Cd)是目前超标率最高的重金属,具有毒性大、移动性强等特点。Cd作为污染最为严重的一种重金属,TCPP作为检出率最高的有机磷系阻燃剂之一,两者在环境中都大量存在,因此,TCPP和Cd为具有代表性的污染物,研究两者的复合作用具有重要意义。本文以赤子爱胜蚓(Eisenia fetida)为受试生物,试验在人工土壤中进行,TCPP单一试验设定浓度为0、5、10、20、40 mg/kg,选用5 mg/kg Cd分别与上述浓度TCPP进行复合试验,染毒之后分别在第7、14、21、28天时取样测定相关指标,测定指标包括:活性氧(ROS)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、谷胱甘肽硫转移酶(GST)活性、丙二醛(MDA)含量和蚯蚓体腔细胞DNA的损伤,对TCPP单一和TCPP与Cd复合污染的毒性进行评估,为TCPP单一和土壤中重金属-有机复合污染的生态风险评价提供理论依据。主要试验结果如下:(1)TCPP单一染毒时对蚯蚓体内酶活性的影响:抗氧化酶系(SOD、CAT、POD)和GST活性均呈现先升高后降低的趋势,ROS含量从第二周之后高于空白对照组,MDA含量第三周之后增加,说明在TCPP胁迫下,ROS含量升高,抗氧化酶系和GST受到刺激并激活开始清除过量的ROS,但长时间的暴露,使抗氧化酶系和GST生产系统受损,活性降低,蚯蚓体内发生了脂质过氧化作用。(2)TCPP单一染毒时蚯蚓体腔细胞DNA的损伤:所有浓度系列的TCPP处理组都可对蚯蚓细胞DNA造成不同程度的损伤,且DNA损伤程度随染毒浓度和时间的增加而增加。(3)TCPP与Cd复合染毒时对蚯蚓体内酶活性的影响:抗氧化酶系(SOD、CAT、POD)活性变化趋势与单一染毒时相似,GST活性从第二周开始被抑制,染毒后期,ROS、MDA两者相较于空白对照组的增加量均高于单一处理组增加量之和,整体来看,两者复合表现出一定程度的协同作用。(4)TCPP与Cd复合染毒时蚯蚓体腔细胞DNA的损伤:蚯蚓体内DNA损伤程度的变化趋势与单一染毒时类似,且损伤程度始终显著高于单一处理组,TCPP和Cd表现出一定程度的协同作用。更多还原

【Abstract】 Tris(2-chloroisopropyl)phosphate(TCPP)is a kind of organophosphorus flame retardants(OPFRs),which has the advantages of low price and good fire retardant effects.As an emerging flame retardant,its market potential is huge,and its production and consumption are increasing year by year,but it is difficult to degrade in the environment.At present,it has been detected in all kinds of environmental media,and also in living organisms including human body,indicating that it can be enriched through the food chain and harm human life and health.Cadmium(Cd)is the heavy metal with the highest rate of over-standard currently,which has the characteristics of high toxicity and strong mobility.Cd is one of the most polluted heavy metals,TCPP is one of the organophosphorus flame retardants with the highest detection rate,both of which are abundant in the environment.Therefore,it is important to study the combination of the two representative pollutants.In this paper,Eisenia fetida was used as the test organism.The experiment was carried out in artificial soil.The TCPP single test set concentration was 0,5,10,20,40 mg/kg,choose 5mg/kg respectively with the Cd concentration TCPP composite experiment,infected after respectively at 7,14,21,28 days sampling determination of relevant indicators,measurement indicators include: Reactive oxygen species(ROS)content,superoxide dismutase(SOD)activity,activity of peroxidase(POD)and catalase(CAT)activity and glutathione s transferase(GST)activity and malondialdehyde(MDA)content and earthworm body cavity cell DNA damage,the TCPP single and TCPP with Cd to evaluate the toxicity of compound pollution,for TCPP single and-organic compound pollution of heavy metals in soil provide theoretical basis for the ecological risk assessment.The main conclusions of this research are as follows:(1)The effects of TCPP on the enzyme activities in earthworms in single exposure: the antioxidant enzymes(SOD,CAT,POD)and GST activities showed a trend of first promotion and then inhibition.The ROS content of the experimental group was always higher than that of the blank group,MDA content increased at the later stage.It indicates that under TCPP stress,the ROS content increases,and the antioxidant enzymes and GST are stimulated and activated to clear excess ROS,but long-term exposure will damage the antioxidant enzymes and GST production system and reduce their activity,Lipid peroxidation occurred in the earthworm body.(2)DNA damage of earthworm under single TCPP exposure: TCPP treatment groups of all concentration series can cause different degrees of damage to earthworm cell DNA,and the degree of DNA damage increased with the increase of exposure concentration and time.(3)The effects of TCPP and Cd compounds on the enzyme activity in earthworms: The activity change trend of the antioxidant enzymes(SOD,CAT,POD)is similar to that of the single poison,but the CAT activity recovers to the control group in the later stage.At the same level,GST activity was inhibited from the second week.In the late stage of exposure,the increase in both ROS and MDA compared with the blank control group was higher than the sum of the increase in the single treatment group.On the whole,the combined performance of the two A certain degree of synergy.(4)DNA damage of earthworm under complex of TCPP and Cd compounds exposure:The changes of DNA damage in earthworms is similar to that of single infection,and the damage is always significantly higher than that of the single treatment group.TCPP and Cd show a certain degree synergy.更多还原