Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
Aquat Toxicol. 2018 May;198:231-239. doi: 10.1016/j.aquatox.2018.03.009. Epub 2018 Mar 10.
Increasing concern has been focused on the potential risks associated with the trophic transfer to aquatic organisms of ambient contaminants in the presence of titanium dioxide nanoparticles (nano-TiO). This study investigated the influence of nano-TiO on the trophic transfer of arsenic (As) from the microalgae Nannochloropsis maritima to the brine shrimp Artemia salina nauplii. We found that nano-TiO could significantly facilitate As sorption on N. maritima within an exposure period of 24 h, and this sorption subsequently led to higher As trophic transfer from the algae to A. salina according to trophic transfer factors (TTF > TTF). However, after 48 h of depuration, the retention of As in A. salina fed As-nano-TiO-contaminated algae was even lower than that in A. salina fed As-contaminated algae at the same exposure concentrations. This result indicates that the increased food chain transfer of As in the presence of nano-TiO can be explained by adsorption of As onto nano-TiO in contaminated food (algae), but the bioavailability of As in A. salina is reduced after the introduction of nanoparticles. Although the stress enzyme activities of superoxide dismutase (SOD) and acetylcholinesterase (AChE) in A. salina at a lower As concentration treatment in the presence of nano-TiO were not significantly changed, they increased with higher exposure concentrations of As with or without nano-TiO. Our study highlighted the complex role of nanomaterials in the transfer of ambient contaminants via trophic chains and the potential of nano-TiO to reduce the bioavailability of As via trophic transfer to saltwater zooplankton.
人们越来越关注在存在二氧化钛纳米颗粒（纳米-TiO）的情况下，环境污染物向水生生物的营养转移可能带来的潜在风险。本研究调查了纳米-TiO 对从微藻海洋盐藻（Nannochloropsis maritima）到卤虫（Artemia salina）无节幼体的砷（As）营养转移的影响。我们发现，纳米-TiO 可以在 24 小时的暴露期内显著促进 As 在 N. maritima 上的吸附，这种吸附随后导致更高的 As 从藻类向 A. salina 的营养转移，根据营养转移因子（TTF>TTF）。然而，经过 48 小时的净化后，在相同暴露浓度下，摄入含有 As 的纳米-TiO 污染藻类的卤虫（A. salina）体内保留的 As 甚至低于摄入含有 As 的污染藻类的卤虫体内的 As。这一结果表明，在纳米-TiO 存在的情况下，As 在食物链中的转移增加可以用 As 吸附到污染食物（藻类）中的纳米-TiO 来解释，但纳米粒子的引入降低了 A. salina 中 As 的生物利用度。虽然在较低的 As 浓度处理下，在纳米-TiO 存在的情况下，卤虫体内的超氧化物歧化酶（SOD）和乙酰胆碱酯酶（AChE）的应激酶活性没有显著变化，但随着 As 暴露浓度的升高，无论是有还是没有纳米-TiO，这些酶活性都有所增加。我们的研究强调了纳米材料在通过食物链传递环境污染物方面的复杂作用，以及纳米-TiO 通过营养转移减少海水浮游动物中 As 生物利用度的潜力。
