The effect of arsenic contaminated sediments on benthic aquatic macroinvertebrates

In the environment arsenic is a naturally occurring metalloid. Well documented cases of arsenic poisoning in countries such as India, Bangladesh and China have indicated that relatively small concentrations may have serious impacts on human health. Although arsenic is naturally occurring, anthropogenic activities, such as gold mining, have resulted in increased local concentrations. Impacts of arsenic contaminated sediment on benthic aquatic macroinvertebrates in unknown. This study used a field-based microcosm experiment to determine whether concentrations of arsenic observed in the field are toxic to aquatic invertebrates and to determine influencing factors of arsenic toxicity in Victorian waterways. In this experiment treatments were spiked with arsenic concentrations ranging from <2 mg/kg to 400 mg/kg which span the concentrations seen in field sediments. Results from this study showed that increased As concentrations decreased daphnia (F(2,48)=5.5, p=<0.001), copepod (F(2,48)=7.8, p=<0.001) and nematode (F(2,48)=23.5, p=