不同形态锑对土壤白符跳(Folsomia candida)的毒性差异

Toxicity differences of different forms of antimony to soil-dwelling springtail(Folsomia candida)

为探讨锑(Sb)形态对Sb毒性的影响,积累和完善Sb的基础毒性数据,为Sb的生态风险评估提供更全面的依据,通过滤纸接触试验、土壤和食物暴露试验,评价并对比了两种形态的锑(Sb~Ⅲ和Sb~Ⅴ)对模式生物白符跳(Folsomia candida)的急性、慢性毒性效应及差异。滤纸试验中跳虫在不同浓度Sb~Ⅴ水溶液浸透的滤纸上暴露3 d和7 d后均无死亡现象,Sb~Ⅲ对跳虫的半数致死浓度(LC_(50))分别为325 mg·L^(-1)(3 d)和244 mg·L^(-1)(7 d);土壤暴露试验中Sb~Ⅲ和Sb~Ⅴ对跳虫逃避行为的半数效应浓度(EC_(50))分别为132、344 mg·kg^(-1),Sb~Ⅲ对跳虫的7 d-LC_(50)为2105 mg·kg^(-1)(Sb~Ⅴ的LC_(50)大于设置的最高浓度),Sb~Ⅲ对跳虫的28 d-LC_(50)为703 mg·kg^(-1)(Sb~Ⅴ的LC_(50)大于设置的最高浓度),Sb~Ⅲ和Sb~Ⅴ对跳虫繁殖的28 d-EC_(50)分别为307、8501 mg·kg^(-1);食物暴露试验中Sb~Ⅲ和Sb~Ⅴ处理下跳虫成虫均无明显死亡,对跳虫繁殖的28 d-EC_(50)分别为433、8798 mg·kg^(-1)。试验结果表明,在设置的浓度范围内Sb~Ⅴ不会直接造成跳虫明显死亡,但会对跳虫的生理行为和繁殖产生一定毒性影响,而Sb~Ⅲ对跳虫存活和繁殖均有较大毒性。因此在评估Sb的毒性效应时既要考虑总量也需考虑形态。

To explore the effect of antimony forms on its toxicity, we evaluated the acute and chronic toxic effects of two forms of antimony（Sb^Ⅲand Sb^Ⅴ）to Folsomia candida using filter paper contact experiment, soil and food exposure experiment. In filter paper contact experiment, the LC（50） values for Sb^Ⅲwere 325 mg·L^（-1）（3 d）, 244 mg·L^（-1）（7 d）, respectively, but the survival of F. candida was not affected by Sb^Ⅴ.In soil exposure experiment, the EC（50） values of acute avoidance were 132, 344 mg·kg^（-1）, respectively;the LC（50） value of acute survival for SbⅢwas 2105 mg·kg^（-1）（the mortality did not reach 50% in setting concentration range of Sb^Ⅴ）;The LC（50） value of chronic survival for Sb^Ⅲwas703 mg·kg^（-1）（the LC（50） for Sb^Ⅴwas higher than the highest antimony concentration）, the EC（50） values of chronic reproduction were 307, 8501mg·kg^（-1）, respectively. In food exposure experiment, there were no obvious death of Folsomia candida in Sb^Ⅲor Sb^Ⅴtreatments, the EC（50） values of chronic reproduction were 433, 8798 mg·kg^（-1）,respectively. The results showed that Sb^Ⅴcould not cause the death of the springtail directly, but impact on its physiological behavior and reproduction, whereas the toxicity of Sb^Ⅲwas more significant than that of Sb^Ⅴ. Therefore, when assessing the toxic effects of Sb, both the total amount and the different forms should be considered. This study can accumulate and supplement the toxicity data as well as provide a more comprehensive basis for ecological risk assessment of Sb.