發(fā)布時間：2018-06-12 01:33

  本文選題：溫度 + 鹽度��； 參考：《浙江工業(yè)大學(xué)》2015年碩士論文

【摘要】：近年來,氣候變化已影響到人類生產(chǎn)、生活的各個方面,然而其在污染物環(huán)境歸趨和毒性中也扮演著重要的角色。氣候變化主要通過改變溫度、鹽度、離子濃度等環(huán)境因素,影響化學(xué)污染物的環(huán)境分布和毒性效應(yīng)。農(nóng)藥是環(huán)境中廣泛存在的一類化學(xué)污染物,而我國使用的農(nóng)藥中約有40%均具有手性結(jié)構(gòu),它們的水生毒性取決于吸收、富集和代謝及其在這些過程中的對映體選擇性。然而,目前對此類農(nóng)藥的水生毒性研究大多還是基于最佳條件下的測試,對不同環(huán)境條件下的毒性研究未見系統(tǒng)和深入報道,特別是環(huán)境因素變化在對映體選擇性毒性中的作用。本課題圍繞氣候變化背景下水環(huán)境的兩個關(guān)鍵因素：溫度、鹽度,以Ⅰ型擬除蟲菊酯-聯(lián)苯菊酯和Ⅱ型擬除蟲菊酯-功夫菊酯為目標(biāo)化合物,以斑馬魚胚胎為模型,研究了手性農(nóng)藥在生物富集和水生毒性的對映體選擇性變化特征以及毒理學(xué)機制。研究結(jié)果表明：隨著暴露溶液溫度(20℃、25℃和30℃)的上升,順式聯(lián)苯菊酯外消旋體cis-BF和功夫菊酯外消旋體(±)-LCT對胚胎的急性毒性和發(fā)育毒性均逐漸增強。從對映體毒性分析表明,它們的毒性效應(yīng)分別主要來自1R-cis-BF和(+)-LCT。隨暴露溶液鹽度(0‰、5‰、10‰和15‰)的上升,cis-BF對胚胎的急性毒性和發(fā)育毒性均顯著增強。通過對代謝和甲狀腺相關(guān)基因表達(dá)量的測定分析發(fā)現(xiàn),溫度或鹽度的升高可能通過影響cis-BF或LCT對相關(guān)基因的表達(dá),干擾了代謝和甲狀腺的正常生理功能,進(jìn)而增強了cis-BF或LCT對斑馬魚胚胎的毒性效應(yīng)。由實驗結(jié)果我們推測,在溫度對cis-BF的毒性影響中,溫度對其作用顯著,而在溫度對LCT的毒性影響中,LCT受到影響相對較��；高鹽度增強了cis-BF的毒性,表現(xiàn)出協(xié)同效應(yīng)。此外,溫度變化對cis-BF和LCT在斑馬魚胚胎中的富集沒有顯著影響,鹽度升高則增加了斑馬魚胚胎對cis-BF的富集作用。
[Abstract]:In recent years, climate change has affected all aspects of human production and life, but it also plays an important role in the environmental trend and toxicity of pollutants. Climate change mainly affects the environmental distribution and toxicity of chemical pollutants by changing environmental factors such as temperature, salinity and ion concentration. Pesticides are a class of chemical pollutants widely existing in the environment, and about 40% of the pesticides used in China have chiral structures. Their aquatic toxicity depends on absorption, enrichment, metabolism and enantioselectivity in these processes. However, most of the current studies on aquatic toxicity of these pesticides are based on tests under optimal conditions, and toxicity studies under different environmental conditions have not been systematically and thoroughly reported. Especially the role of environmental factors in enantioselective toxicity. This paper focuses on two key factors of water environment: temperature, salinity, taking type I pyrethroid bifenthrin and type II pyrethroid-kungthrin as target compounds and zebrafish embryos as model. The enantioselectivity and toxicological mechanism of chiral pesticides in bioconcentration and aquatic toxicity were studied. The results showed that the acute toxicity and developmental toxicity of cis-bifenthrin racem-cis-BF and cypermethrin racemate (鹵+ -LCT) increased with the increase of exposure solution temperature (20 鈩，

本文編號：2007647