Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada; Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada; Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada.
Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada.
Ecotoxicol Environ Saf. 2018 Sep 30;160:162-170. doi: 10.1016/j.ecoenv.2018.05.029. Epub 2018 May 26.
Nickel (Ni) emissions resulting from production and transportation raise concerns about the impact of Ni exposure to marine ecosystems. Ni bioavailability models are established for FW systems, but the influence of chemical parameters (e.g. dissolved organic carbon (DOC)) on Ni toxicity within marine systems is less well understood. To examine the effects of DOC concentration and composition on Ni toxicity, acute toxicity tests were conducted on early life-stages of blue mussels (Mytilus edulis) and sea urchin embryos (Strongylocentrotus purpuratus) in full strength sea water (32 ppt). Nine different field collected samples of water with varying concentration (up to 4.5 mg C/L) and composition of DOC were collected from the east coast of the United States. Organic matter compositional analysis included molecular fluorescence and absorbance spectroscopy. The different DOC sources had different protective effects against embryo toxicity. The control (no DOC) Ni 48 h-EC for Mytilus embryos was 133 µg/L (95% confidence interval (C.I.) of 123-144 µg/L), while Strongylocentrotus embryos displayed control 96-h EC values of 207 µg/L (167-247 µg/L). The most significantly protective sample had high humic acid concentrations (as determined from fluorescence spectroscopy), which yielded an EC of 195 µg/L (169-222 µg/L) for Mytilus, and an EC of 394 µg/L (369-419 µg/L) for S. purpuratus. Among all samples, protection was related to both DOC quantity and quality, with fluorescence-resolved humic and fulvic acid concentrations showing the strongest correlations with protection for both species. These data suggest that DOC is protective against Ni toxicity in M. edulis and S. purpuratus, and that accounting for a DOC quality factor will improve predictive toxicity models such as the biotic ligand model.
镍（Ni）的排放源于生产和运输过程，这引起了人们对 Ni 暴露对海洋生态系统影响的关注。已建立了淡水系统中 Ni 生物有效性模型，但对于海洋系统中化学参数（如溶解有机碳（DOC））对 Ni 毒性的影响了解较少。为了研究 DOC 浓度和组成对 Ni 毒性的影响，在全盐度海水（32 ppt）中对贻贝（Mytilus edulis）早期生命阶段和海胆胚胎（Strongylocentrotus purpuratus）进行了急性毒性试验。从美国东海岸采集了 9 种不同浓度（高达 4.5mgC/L）和组成的 DOC 的现场水样。有机物质组成分析包括分子荧光和吸收光谱。不同的 DOC 来源对胚胎毒性具有不同的保护作用。贻贝胚胎的对照（无 DOC）Ni 48 小时-EC 为 133µg/L（95%置信区间（CI）为 123-144µg/L），而 Strongylocentrotus 胚胎的对照 96 小时-EC 值为 207µg/L（167-247µg/L）。保护作用最显著的样本具有较高的腐殖酸浓度（通过荧光光谱法确定），这使得贻贝的 EC 为 195µg/L（169-222µg/L），S. purpuratus 的 EC 为 394µg/L（369-419µg/L）。在所有样本中，保护作用与 DOC 数量和质量有关，荧光分辨腐殖酸和富里酸浓度与两种物种的保护作用相关性最强。这些数据表明，DOC 可保护贻贝和海胆免受 Ni 毒性的影响，并且考虑到 DOC 质量因素将改善生物配体模型等预测毒性模型。
