Why Mercury is a Problem
Mercury is one of the biggest toxic air pollutants and has an adverse impact on our health and our environment. We are exposed to it just by breathing contaminated air, eating contaminated food products (especially fish, but also meat, milk or eggs), drinking water, or simply by touching water, soil or dust.
The main problem with mercury is that it never degrades, but rather remains in our environment forever. The good news is the Environmental Protection Agency can protect us from it -but there is still a long way to go.
The largest emitters of mercury are electric utility plants (primarily coal-fired plants). Once these plants release mercury, it eventually falls to earth in the form of rain and is deposited in soil or bodies of water. Check out the cycle here.
Because of the water cycle, the environment and the species that inhabit it - including humans - are constantly exposed to mercury and its subsequent health risks. For instance, fish-eating birds and mammals are more highly exposed to mercury than any other known component of aquatic ecosystems. Adverse effects of mercury on fish, birds and mammals include death, reduced reproductive success, impaired growth and development, and behavioral abnormalities.
Also, because mercury pollutes bodies of water, it accumulates in food chains and in predator fish. Some fish species accumulate levels that are concerning, because they are older and are exposed for a longer period of time to the mercury in the water, or simply because they are more sensitive. The ingestion of mercury-contaminated fish is one of the most significant sources of mercury exposure to people in the United States.
Although its consumption can damage an adult's nervous system, mercury's most severe effects are on developing fetuses in pregnant women. The first symptoms of poisoning include lack of coordination and a burning or tingling sensation in the fingers and toes. As mercury levels increase, your ability to walk, talk, see and hear may also be affected (PDF).
The regulation of mercury in the U.S. is based in two specific laws: The Mercury Export Ban Act of 2008 (PDF) and the Mercury-Containing and Rechargeable Battery Management Act of 1996. However, because mercury is often released through emissions from manufacturing, use, or disposal activities, its regulation also includes legislation to control some mercury emissions to air, water, or from wastes and products. This is done under certain Federal environmental statutes, such as the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act.
In addition, states also develop their own safeguards to address mercury emissions. For instance, when the concentration is high enough, the states establish fish consumption advisories. Find your fish advisory for where you live at this link, especially if you are expecting.
Because the long-term solution to mercury pollution is to minimize global mercury use and releases, one of the most important statutes for our work at Sierra Club is the Clean Air Act. The Clean Air Act has a forty year track record of protecting our health and welfare, and includes special provisions for dealing with air toxics emitted from utilities giving EPA the authority to protect Americans from power plant mercury emissions by establishing "performance standards" or "maximum achievable control technology" (MACT).
This March we expect EPA to announce an updated air quality standard for life-threatening hazardous air pollution from power plants, such as mercury and arsenic. Under this safeguard for power plants, new power plants will be required to reduce their hazardous air pollution to match the best-performing and cleanest plants for each type of pollutant.
Sierra Club supports EPA safeguards that will protect public health and the environment by reducing mercury emissions and global warming pollution.
-- Elizabeth Lopez, Sierra Club Global Warming & Energy Team