Heavy metal pollution in Antarctica and its potential impacts on algae

Antarctica is not free from environmental pollutants although it is often perceived as the last pristine continent on Earth. Research stations represent one of the largest forms of anthropogenic activity and are the main source of locally derived contamination in Antarctica. Elevated levels of heavy metals such as copper (Cu), lead (Pb) and mercury (Hg) have been detected in Antarctica. Fuel combustion, accidental oil spills, waste incineration and sewage disposal are amongst the primary sources of heavy metal contaminants in Antarctica, besides natural sources such as animal excrements and volcanism. Studies on the impacts of heavy metals on biota in Antarctica have been focused mainly on invertebrates and cryptogams but not on algae. However, adverse impacts of heavy metals on sensitive algae may affect organisms at the higher trophic levels, and consequently disrupt Antarctic food chains. Heavy metals may be accumulated by algae and biomagnified through the food chain. The sensitivity and response of Antarctic algae to heavy metal toxicity have not been well studied. Robust toxicity protocols for the testing of the impacts of heavy metals on Antarctic algae need to be developed. This review aims to give an overview of the status of heavy metal pollution in Antarctica and its potential impacts on algae.