Meador James P
Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington, USA.
Environ Toxicol Chem. 2015 Jun;34(6):1309-19. doi: 10.1002/etc.2910. Epub 2015 May 1.
The present study examined the available literature linking whole-body tissue concentrations with toxic effects in fish species for copper and cadmium. The variability in effect concentration for both copper and cadmium among species occurred within an order of magnitude for all responses, whereas the range for lethal toxicity based on water exposure spanned approximately 4 to 5 orders of magnitude. Fish tissue concentrations causing adverse effects were just above background concentrations, occurring between 1 μg/g and 10 μg/g for copper and 0.1 μg/g to 4 μg/g for cadmium. The results also show that salmonids are especially sensitive to cadmium, which appears to be a function of chemical potency. No studies were found that indicated adverse effects without increases in whole-body concentration of these metals. This narrow range for dose-response implies that a toxicological spillover point occurs when the detoxification capacity of various tissues within the animal are exceeded, and this likely occurs at a similar whole-body concentration for all naïvely exposed fish species. Elevated whole-body concentrations in fish from the field may be indicative of possible acclimation to metals that may or may not result in effects for target species. Acclimation concentrations may be useful in that they signal excessive metal concentrations in water, sediment, or prey species for a given site and indicate likely toxic effects for species unable to acclimate to excess metal exposure. Using tissue residues as the dose metric for these metals provides another line of evidence for assessing impaired ecosystems and greater confidence that hazard concentrations are protective for all fish species.
本研究调查了将鱼类全身组织浓度与铜和镉的毒性效应联系起来的现有文献。对于所有反应，铜和镉在物种间的效应浓度变化在一个数量级内，而基于水体暴露的致死毒性范围跨越约4至5个数量级。导致不良反应的鱼类组织浓度仅略高于背景浓度，铜的浓度在1μg/g至10μg/g之间，镉的浓度在0.1μg/g至4μg/g之间。结果还表明，鲑科鱼类对镉特别敏感，这似乎是化学效力的一种表现。未发现有研究表明在这些金属的全身浓度未增加的情况下会产生不良反应。这种狭窄的剂量 - 反应范围意味着当动物体内各种组织的解毒能力被超过时，就会出现毒理学溢出点，并且这可能在所有初次暴露的鱼类物种的相似全身浓度下发生。野外鱼类全身浓度升高可能表明对金属的可能适应，这可能对目标物种产生影响，也可能不会。适应浓度可能有用，因为它们表明给定地点的水、沉积物或猎物物种中金属浓度过高，并表明无法适应过量金属暴露的物种可能产生的毒性效应。使用组织残留量作为这些金属的剂量指标为评估受损生态系统提供了另一线证据，并更有信心认为危害浓度对所有鱼类物种都具有保护作用。
