Hanna Shannon K, Miller Robert J, Lenihan Hunter S
Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106-5131, USA.
Marine Science Institute, University of California, Santa Barbara, CA 93106-6150, USA.
Nanomaterials (Basel). 2014 Jun 27;4(3):535-547. doi: 10.3390/nano4030535.
Cu is an essential trace element but can be highly toxic to aquatic organisms at elevated concentrations. Greater use of CuO engineered nanoparticles (ENPs) may lead to increased concentrations of CuO ENPs in aquatic environments causing potential ecological injury. We examined the toxicity of CuO ENPs to marine mussels and the influence of mussels on the fate and transport of CuO ENPs. We exposed marine mussels to 1, 2, or 3 mg L CuO ENPs for four weeks, and measured clearance rate, rejection, excretion and accumulation of Cu, and mussel shell growth. Mussel clearance rate was 48% less, and growth was 68% less, in mussels exposed to 3 mg L than in control animals. Previous studies show 100% mortality at 1 mg Cu L, suggesting that CuO ENPs are much less toxic than ionic Cu, probably due to the slow dissolution rate of the ENPs. Mussels rejected and excreted CuO ENPs in biodeposits containing as much as 110 mg Cu g, suggesting the potential for magnification in sediments. Mussels exposed to 3 mg L CuO ENPs accumulated 79.14 ± 12.46 µg Cu g dry weight, which was 60 times more Cu than in control animals. Our results suggest that mussels have the potential to influence the fate and transport of CuO ENPs and potentially cause magnification of CuO ENPs in mussel bed communities, creating a significant source of Cu to marine benthos.
铜是一种必需的微量元素，但在浓度升高时对水生生物具有高毒性。更多地使用氧化铜工程纳米颗粒（ENPs）可能会导致水生环境中氧化铜ENPs的浓度增加，从而造成潜在的生态损害。我们研究了氧化铜ENPs对海洋贻贝的毒性以及贻贝对氧化铜ENPs归宿和迁移的影响。我们将海洋贻贝暴露于1、2或3 mg/L的氧化铜ENPs中四周，并测量清除率、排异率、铜的排泄和积累以及贻贝壳的生长情况。暴露于3 mg/L的贻贝的清除率比对照动物低48%，生长比对照动物低68%。先前的研究表明，在1 mg/L的铜离子浓度下死亡率为100%，这表明氧化铜ENPs的毒性远低于离子铜，可能是由于ENPs的溶解速度较慢。贻贝在含有高达110 mg/g铜的生物沉积物中排异并排泄氧化铜ENPs，这表明在沉积物中有生物放大的可能性。暴露于3 mg/L氧化铜ENPs的贻贝积累了79.14±12.46 µg/g干重的铜，是对照动物的60倍。我们的结果表明，贻贝有可能影响氧化铜ENPs的归宿和迁移，并可能导致贻贝床群落中氧化铜ENPs的生物放大，从而成为海洋底栖生物的一个重要铜源。
