吐纳麝香与镉联合暴露对赤子爱胜蚓体内谷胱甘肽与金属硫蛋白的影响

Effect of Joint Exposure to Polycyclic Musk and Cadmium on Glutathione and Metallothionein in Eisenia foetida

广泛应用于个人护理产品和香味添加剂中的吐纳麝香(6-乙酰基-1,1,2,4,4,7-六甲基四氢萘,AHTN)是一种新型污染物,重金属镉(Cd2+)是土壤中常见的污染物,两者在土壤生态系统中存在联合暴露的可能。实验以赤子爱胜蚓为受试生物,通过24h暴露滤纸染毒实验测试了AHTN单一,Cd2+单一,以及AHTN与Cd2+联合暴露条件下蚯蚓体内谷胱甘肽(GSH)和金属硫蛋白(MT)的变化趋势。结果显示:Cd2+单一暴露时,GSH与MT随Cd剂量增加有明显上升趋势;AHTN单一暴露时,随着AHTN剂量增加,GSH与MT同步呈现先增多后减少的趋势;联合暴露情况下,AHTN在高剂量下对MT与GSH同样产生了抑制作用,使Cd2+对MT的诱导未达到Cd2+单一染毒时的水平。

Polycyclic musks （PCMs）, such as 6-acetyl-1,1,2,4,4,7-hexamethy ltetralin （AHTN）, which are widely used in personal care products as fragrance additive, are considered as emerging pollutants. As cadmium is the regular contaminant in soil, the combined exposure of AHTN and Cd is possible in soil. In order to investigate the bioeffect of this combined exposure, Eisenia foetida was exposed on contaminated filter paper for 24 hours to detect the concentration of glutathionein （GSH） and metallothionein （MT） during the exposure. The contaminants were single AHTN, single Cd2＋, and joint AHTN and Cd2＋, respectively. Single Cd2＋ exposure significantly increased the content of GSH and MT with increasing the dose of Cd2＋. The contents of GSH and MT were both enhanced in the AHTN exposure with low dosage, and reduced in the AHTN exposure with high dosage. In the combined exposure, GSH and MT were inhibited at high dose range of AHTN, leading to lower MT level than that in the single Cd2＋ exposure.