中文摘要：

全氟辛烷磺酸（PFOS）是广受关注的持久性有机污染物之一.PFOS广泛存在于河口和近海岸等复杂盐度区,然而目前对不同盐度影响下的PFOS毒理行为研究较少.本文以海水青鳉（Oryzias melastigma）鱼为模型,比较不同盐度条件下,PFOS暴露对鱼卵孵化和发育的影响.结果表明,PFOS在鱼卵内的蓄积量随着盐度升高而呈现上升的趋势.在低盐度和高盐度下,PFOS暴露均提高鱼卵孵化率,而低盐度下的两周孵化率比高盐度高.进一步比较了3种盐度下（30‰,15‰和5‰）PFOS对鱼卵心脏发育相关基因表达影响的差异.PFOS对过氧化物酶体增殖物激活受体（PPAR）的调节受盐度的影响,PPAR和PPAR的表达量在低盐度下相对高盐度下高.盐度对PFOS调节环加氧酶（COX-2）和心脏相关蛋白（SMYD1）的作用效果与PPAR相似.而盐度不影响PFOS对心脏发育特异性转录因子（GATA4和BMP4）和钠钾离子ATP酶（ATPase）的调节作用.研究结果揭示了盐度是全氟类化合物毒性的一个影响因素,有助于广盐度地区PFCs化合物的毒性评估.

英文摘要：

Perfluorooctane sulfonate（PFOS） received great attention as one of the persistent organic contaminants.Despite the widespread occurrence of PFOS in estuarine and coastal waters,there is little report about the effect of salinity on the toxicological behaviors of this chemical.In the study,the effects of PFOS on the hatching and development of fish embryos under various water salinities were studied by marine fish model-Oryzias melastigma.The results showed that the increasing in salinity lead to a generally elevated bioaccumulation of PFOS in the embryos.The hatching rate of the fish increased upon PFOS exposure under both the low and high salinity.The hatching rate were relatively higher under low water salinity than high salinity.The impact of PFOS on the expression of development related genes were investigated under 30‰,15‰ and 5‰ water salinities.The relative expression level of peroxisome proliferator-activated receptor（PPAR） were different after exposure to the same concentration of PFOS under various water salinities.PFOS induced more mRNA transcript of both PPAR and PPAR at low salinity than at high salinity.The similar effects were observed with cyclooxygenase-2（COX-2） and SMYD1 genes.In contrast,Salinity does not have impacts on the effect of PFOS on the mRNA levels of Na＋-K＋-ATPase,GATA-binding protein 4 and bone morphogenetic protein 4.In all,this study revealed that salinity has an impact on the toxicological behavior of PFOS from bioaccumulation level to toxicological effect level.The toxicological behavior of PFOS is different under different water salinity.Salinity is an environmental factor that could affect the toxicity of PFOS and this will be helpful for assessing toxicological effects of PFCs in the environment with varied salinities.