Distribution Mechanisms: Mercury and you
Mercury Emissions
Coal-fired power plants emit many unfavorable toxins into the atmosphere. Nitrogen oxide, sulphur dioxide, and mercury are some of the more voluminous and harmful emissions concerning mercury concentrations in humans (Knightes, Christopher D., et al., 2010). Mercury is emitted as atmospheric organic mercury and travels across the globe until it comes to rest and accumulates on land and in bodies of water. This mercury in it's natural state is found in small amounts and not considered hazardous for human ingestion as it can be passed through the digestive system without accumulation.
Methylmercury
Organic atmospheric mercury is distributed on water bodies and zooplankton and surface algae en masse. These algae die, sink, degrade, and are consumed by bacteria to create methylmercury–a bioaccumulative environmental toxicant. Methylmercury is consumed by small fish, which are consumed by larger fish, which are consumed by animals at the top of the food chain.
Bioaccumulative Contributors
The data show that larger and older fish generally have higher levels of methylmercury contamination (Rasmussen, Joseph B., and Marc Trudel, 2006). Environmental and anthropogenic processes and the degree to which they contribute, however, are still in debate by scientists. Higher levels of methylmercury are found where water bodies meet new sediment sources, such as newly flooded reservoirs or disturbed soils and sediment runoff from logging and wildfires (Van Furl, Chad, John A. Colman, and Michael H. Bothner, 2010). The acidification of water also plays a role in the rate of accumulation in fish samples. Unfortunately, the sulphur dioxide byproducts of coal-fired power plants are a major contributor to global water acidification, amplifying the damage done by their mercury emissions.
Coal-fired power plants emit many unfavorable toxins into the atmosphere. Nitrogen oxide, sulphur dioxide, and mercury are some of the more voluminous and harmful emissions concerning mercury concentrations in humans (Knightes, Christopher D., et al., 2010). Mercury is emitted as atmospheric organic mercury and travels across the globe until it comes to rest and accumulates on land and in bodies of water. This mercury in it's natural state is found in small amounts and not considered hazardous for human ingestion as it can be passed through the digestive system without accumulation.
Methylmercury
Organic atmospheric mercury is distributed on water bodies and zooplankton and surface algae en masse. These algae die, sink, degrade, and are consumed by bacteria to create methylmercury–a bioaccumulative environmental toxicant. Methylmercury is consumed by small fish, which are consumed by larger fish, which are consumed by animals at the top of the food chain.
Bioaccumulative Contributors
The data show that larger and older fish generally have higher levels of methylmercury contamination (Rasmussen, Joseph B., and Marc Trudel, 2006). Environmental and anthropogenic processes and the degree to which they contribute, however, are still in debate by scientists. Higher levels of methylmercury are found where water bodies meet new sediment sources, such as newly flooded reservoirs or disturbed soils and sediment runoff from logging and wildfires (Van Furl, Chad, John A. Colman, and Michael H. Bothner, 2010). The acidification of water also plays a role in the rate of accumulation in fish samples. Unfortunately, the sulphur dioxide byproducts of coal-fired power plants are a major contributor to global water acidification, amplifying the damage done by their mercury emissions.
How is Bioaccumulation Measured?
Mercury (Hg) bioaccumulation factors (BAFs) for game fishes are widely employed for monitoring, assessment, and regulatory purposes. Mercury BAFs are calculated as the fish Hg concentration (Hgfish) divided by the water Hg concentration (Hgwater) and, consequently, are sensitive to sampling and analysis artifacts for fish and water (Riva-Murray et al., 2013).
Fish Bioaccumulation Factors (BAFs) are used to develop Total Maximum Daily Load (TMDL) estimates for management of mercury (Hg) loading to freshwater ecosystems in the United States. BAFs are also used for wildlife and human exposure assessments as well as for remediation assessments at Superfund and other Hg contaminated sites. The United States Environmental Protection Agency (USEPA) recommends site-specific fish BAFs, requiring collection of representative fish and water Hg samples (ACS.org).
Mercury (Hg) bioaccumulation factors (BAFs) for game fishes are widely employed for monitoring, assessment, and regulatory purposes. Mercury BAFs are calculated as the fish Hg concentration (Hgfish) divided by the water Hg concentration (Hgwater) and, consequently, are sensitive to sampling and analysis artifacts for fish and water (Riva-Murray et al., 2013).
Fish Bioaccumulation Factors (BAFs) are used to develop Total Maximum Daily Load (TMDL) estimates for management of mercury (Hg) loading to freshwater ecosystems in the United States. BAFs are also used for wildlife and human exposure assessments as well as for remediation assessments at Superfund and other Hg contaminated sites. The United States Environmental Protection Agency (USEPA) recommends site-specific fish BAFs, requiring collection of representative fish and water Hg samples (ACS.org).