Mercury Wet Deposition: An Australian Study to assess impact of Coal Fired Power Stations
Mercury is a potent neurotoxin which even at low levels causes subtle but permanent harm. Newborns suffer neuro-developmental harm due to fetal mercury exposure from their mothers’ consumption of mercury-contaminated fish. Mercury in lakes, other aquatic media and soils are a direct result of mercury emissions that fall back to the earth and water bodies via the wet (rainfall) and dry (gases and particles) modes of deposition. Coal combustion is a major contributor to mercury emissions to the atmosphere and Australia is heavily dependent on coal-fired power stations for electricity generation.
In this study, total mercury analysis has been done for rainwater sampled using wet-only deposition samplers and ambient air sampled with gold traps. Cold vapor atomic fluorescence spectrophotometry was employed for chemical analysis. Samples have been collected from the Hunter Valley which has two of the major power stations for the NSW region, and from a site in the outskirts of Sydney. The results of this preliminary one year study, which aims to assess the contribution of coal-fired power stations as an airborne source for deposited mercury, will be discussed.