The sensitivity of Antarctic marine amphipods to environmental pollutants and the effects of UV light exposure on amphipods exposed to toxins

The sensitivities of three species of necrophagous marine amphipods to a range of reference toxicants in the water and the effect of UV light exposure on the sensitivity of fluroanthene exposed (a PAH compound derived from fuel oils and present in Winter Quarters Bay sediments) and Winter Quarters Bay (WQB) sediment exposed amphipods was investigated in laboratory exposure experiments. Adults and juveniles of three species of amphipods, Orchomene plebs, Orchomene pinguides and Paramoeia walkeri, were captured near Scott Base and used in the investigation. To determine the sensitivity to toxins, static toxicity tests using a range of 8 different types of toxicants with solution replacements were run for a durations of 4 to 14 days. Tests used 3 replicates at each exposure concentration and 5 control replicates. Up to six widely spaced concentrations were used for each test. To determine the effects of UV light exposure on PAH exposed amphipods, laboratory exposure to fluroanthene, as well as laboratory and in situ exposures to WQB sediments was conducted. In the laboratory, animals were exposed to a range of fluroanthene concentrations under identical test conditions to those outlined for reference toxicants but in reduced lighting. Appropriate solvent and non sunlight controls were conducted. Following four days of exposure to fluroanthene, animals were transferred to clean seawater and exposed to ambient sunlight for two hours. Animals were then returned to low light conditions. Mortality of UV exposed animals was assessed following sunlight exposure and after a further five hours in low light conditions. Concurrently, sediment was sampled from the heavily polluted WQB and animals were exposed in the laboratory and in situ in cages on the sea floor in WQB. At the completion of the exposures, animals were transferred to clean conditions and exposed to direct sunlight for 2 hours. Mortality was assessed as for reference toxicity tests. The determination of rates of toxicant uptake and elimination can enable predictions to be made regarding the potential for bio concentration of substances within organisms and the potential for bioaccumulation of substances in the Antarctica marine ecosystem.