| Summary: | Although chemical studies are included routinely in environmental monitoring programs, chemical data are often not absolute values with unambiguous ecological meaning. Nevertheless, most guidelines that govern permissible discharge concentrations or decisions about whether to remediate contaminated sites are based on the concentrations of contaminants in sediments or water rather than more involved and costly studies based on the identification of biological impacts. The example of heavy metal contamination leaching from an abandoned waste disposal site into the marine environment near Casey Station is used to explore the effects of extraction method (partial extraction using 1M HCl and a total digest with (HF + HNO₃ + HC1) on the interpretation of heavy metal analyses. Data from the partial extraction most clearly distinguished between control and impacted sites. There was a close association between 1M HC1 heavy metal data from sediments and heavy metals concentrations in tissues of the bivalve, Laternula elliptica and the heart urchins, Abatus nimrodi and A. ingens, collected at the same sites. There was no such association between the total digest data and the biota. Unless levels of chemicals in the environment are of concern per se, chemical monitoring must reflect effects on the biota. Analyses of heavy metals based on partial extraction using 1M HC1 provide biologically meaningful data. When the dose/response characteristics of Antarctic biota are better understood, data from partial extractions may be a useful proxy for monitoring the biological effects of heavy metals.
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