Abstract：
Arsenic (As) can be transferred along the food chain, while little is known about the toxic effects of dietborne As on marine copepods. In this study, we investigated the short-term and long-term effects of waterborne and dietborne As exposure on the bioaccumulation and biotransformation, as well as developmental toxicity of Tigriopus japonicus. Under acute As exposure, As bioaccumulation increased and reached a plateau with increasing exposure concentration. Moreover, As accumulation at dietborne exposure was 4.3 and 5.7 times greater than that at control group for AsIII and AsV, respectively. At chronic As exposure, As accumulation increased continuously with exposure time, with a 2.8-day extension of development time and a 45% reduction in 10-d fecundity under dietborne exposure compared to control, whereas 2.3-day extension of development time and a 20% reduction in 10-d fecundity were observed under waterborne exposure. Among As species, inorganic As had the highest concentrations, but the proportion of inorganic As decreased from 89% to 63% during 4 to 21 d of exposure, suggesting the conversion of inorganic As to organic As. The organic As was dominated by arsenobetaine (AsB, 13-25%), followed by monomethylarsenic (MMA, 8-25%). These results suggest that dietborne exposure has more pronounced toxic effects on T. japonicus, but the toxicity of As could be reduced through biotransformation under chronic exposure. Therefore, the arsenic species should be considered when assessing As toxicity.
摘要：
砷（As）可以沿着食物链转移，虽然对食源性As对海洋co足类动物的毒性作用知之甚少。在这项研究中,我们研究了水和食源性As暴露对生物积累和生物转化的短期和长期影响，以及日本虎杖的发育毒性。在急性As暴露下，随着生物累积的增加，并随着暴露浓度的增加而达到平稳状态。此外，由于AsIII和AsV在饮食中的积累是对照组的4.3和5.7倍，分别。在慢性暴露时，随着暴露时间的增加，积累不断增加，与对照组相比，在饮食暴露下，发育时间延长2.8天，繁殖力降低10天，而在水中暴露下，发育时间延长了2.3天，繁殖力减少了20％。在物种中，无机砷的浓度最高，但是无机砷的比例在4到21天的暴露期间从89%下降到63%，表明无机砷转化为有机砷。有机砷以砷甜菜碱(AsB，13-25%），其次是单甲基砷(MMA，8-25%）。这些结果表明，食源性暴露对T.japonicus具有更明显的毒性作用，但是在长期暴露下，As的毒性可以通过生物转化来降低。因此,在评估As毒性时，应考虑砷的种类。
