Department of Biology, Lakehead University, Thunder Bay, Ontario, P1B 8L7 Canada.
Environ Sci Technol. 2012 Aug 21;46(16):9019-26. doi: 10.1021/es300670p. Epub 2012 Jul 27.
The current gill-based Biotic Ligand Model (gbBLM) is an acute-toxicity model used to predict site-specific safe copper (Cu) concentrations. Recent effort to develop a chronic BLM has focused on the olfactory epithelium. To further this effort, the current study looked at the effect of varying Cu concentration and exposure duration on Cu-induced olfactory dysfunction, and whether calcium (Ca) protected against Cu-induced impairment as it does at the gill. Fathead minnows (Pimephales promelas) were treated with five Cu concentrations for varying exposure durations in hard and soft water. A neurophysiological technique, electro-olfactography (EOG), was employed to determine the level of olfactory dysfunction. At the low, ecologically relevant Cu concentrations tested there was significant inhibition of EOG function; however, over time there was at least a partial recovery of olfactory function, despite the continuous Cu exposure. Calcium did not appear to protect against Cu-induced olfactory dysfunction; and even alone, Ca appeared to interfere with the olfactory response to the amino acid L-arginine. Safe copper concentrations as predicted by the gbBLM, chemosensory-based BLMs, the USEPA BLM, and hardness-adjustment equations based on the exposure waters were not entirely protective against olfactory dysfunction.
当前基于鳃的生物配体模型（gbBLM）是一种用于预测特定地点安全铜（Cu）浓度的急性毒性模型。最近开发慢性 BLM 的努力集中在嗅觉上皮上。为了进一步推进这项工作，本研究着眼于 Cu 浓度和暴露时间的变化对 Cu 诱导的嗅觉功能障碍的影响，以及 Ca 是否像在鳃中那样对 Cu 诱导的损伤具有保护作用。褐鳟（Pimephales promelas）在硬水和软水条件下用五种 Cu 浓度处理不同的暴露时间。采用电嗅图（EOG）这一神经生理学技术来确定嗅觉功能障碍的程度。在测试的低、生态相关 Cu 浓度下，EOG 功能受到显著抑制；然而，随着时间的推移，尽管持续暴露 Cu，嗅觉功能至少部分恢复。Ca 似乎不能防止 Cu 引起的嗅觉功能障碍；而且 Ca 本身似乎会干扰对氨基酸 L-精氨酸的嗅觉反应。gbBLM、基于化学感觉的 BLM、USEPA BLM 预测的安全 Cu 浓度以及基于暴露水的硬度调整方程并不能完全防止嗅觉功能障碍。
