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Sci Total Environ. 2011 Sep 15;409(20):4187-97. doi: 10.1016/j.scitotenv.2011.06.061. Epub 2011 Aug 4.
Laboratory studies have traditionally indicated that aquatic insects are relatively insensitive to metals while field studies have suggested them to be among the most sensitive aquatic invertebrate taxa. We reviewed and synthesized available studies in the literature to critically assess why this discrepancy exists. Despite the intense effort to study the effects of metals on aquatic biota over the past several decades, we found studies specific to insects to still be relatively limited. In general, the discrepancy between laboratory and field studies continues with few efforts having been made to elucidate the ecological and physiological mechanisms that underlie the relative sensitivity (or insensitivity) of aquatic insects to metals. However, given the limited data available, it appears that aquatic insects are indeed relatively insensitive to acute metal exposures. In contrast, we suggest that some aquatic insect taxa may be quite sensitive to chronic metal exposure and in some cases may not be protected by existing water quality criteria for metals. The discrepancy between laboratory and field studies with respect to chronic sensitivity appears to largely be driven by the relatively short exposure periods in laboratory studies as compared to field studies. It also appears that, in some cases, the sensitivity of aquatic insects in field studies may be the result of direct effects on primary producers, which lead to indirect effects via the food chain on aquatic insects. Finally, available evidence suggests that diet is an important source of metal accumulation in insects, but to date there have been no conclusive studies evaluating whether dietary metal accumulation causes toxicity. There is a clear need for developing a more mechanistic understanding of aquatic insect sensitivity to metals in long-term laboratory and field studies.
实验室研究传统上表明水生昆虫对金属相对不敏感，而野外研究表明它们是最敏感的水生无脊椎动物类群之一。我们回顾和综合了文献中可用的研究，以批判性地评估这种差异存在的原因。尽管在过去几十年里，人们一直在努力研究金属对水生生物群的影响，但我们发现专门针对昆虫的研究仍然相对有限。一般来说，实验室研究和野外研究之间的差异仍然存在，很少有研究致力于阐明水生昆虫对金属相对敏感（或不敏感）的生态和生理机制。然而，鉴于可用数据有限，似乎水生昆虫确实对急性金属暴露相对不敏感。相比之下，我们认为一些水生昆虫类群可能对慢性金属暴露相当敏感，在某些情况下，现有的金属水质标准可能无法保护它们。与慢性敏感性相关的实验室研究和野外研究之间的差异主要是由于实验室研究的暴露期相对较短，而野外研究的暴露期相对较长。似乎在某些情况下，野外研究中水生昆虫的敏感性可能是直接作用于初级生产者的结果，这通过食物链对水生昆虫产生间接影响。最后，现有证据表明，饮食是昆虫金属积累的一个重要来源，但迄今为止，还没有研究评估饮食中金属积累是否会导致毒性。目前迫切需要在长期实验室和野外研究中，对水生昆虫对金属的敏感性有更深入的了解。
