Use this Guide to learn about mercury, understand its environmental and health effects, safely manage products and wastes that contain it, and find out what Massachusetts and other states in the region are doing to reduce mercury exposure.
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MassDEP Mercury Information
Table of Contents
Mercury is Everywhere
Mercury is a naturally occurring metallic element that is toxic to people and the environment. It is found in many common items at home, school and work, including:
- Fluorescent bulbs
- Some topical disinfectants, older medications, nasal sprays, ointments, and contact lens solutions.
- Certain bleaches, detergents, stain removers, and soaps.
- Batteries, latex paint, and pesticides made before 1990;
- Button batteries found in watches, calculators, hearing aids, and electronics;
- Pilot lights in gas appliances; and
- Switches in certain automatic shut-off irons, car trunks, fire alarms, and septic tanks.
Mercury won't harm you if it stays inside an item. But when a product containing it is broken, thrown in the trash, or poured down the drain, mercury accumulates in the environment, polluting air and water, and accumulating in fish.
- Mercury most commonly poisons humans through:
- Inhalation; by breathing invisible vapors
- Ingestion; by eating contaminated fish
- Dermal absorption; by touching mercury directly.
- Protect yourself and your family by:
- Avoid putting mercury-containing products in the trash or down the drain. Many communities have household hazardous waste collection events or sites where you can safely dispose of these items. Learn more about where to dispose of mercury products and other household hazardous products at Recyclopedia.
- Never touch spilled mercury. Keep people and pets away and open windows to ventilate the area. Don't sweep or vacuum spilled mercury up! If a person or a pet has come into contact with mercury, contact a medical professional immediately.
- Check product labels. Buy mercury-free alternatives whenever they are available.
- Be aware of fish consumption advisories. Eating fish contaminated with mercury can harm you and your family.
Environmental Effects of Mercury
Mercury can be found at low levels almost everywhere, but the burning of coal and trash have greatly increased its levels in the environment.
The environmental impacts of mercury can be local, or carried across whole regions or entire continents by the wind.
In lakes, ponds, and the ocean, mercury can be transformed by natural processes into a more toxic form called methylmercury, which enters the food chain when small organisms absorb it.
- Fish. Small fish eat contaminated plankton and algae, then in turn are eaten by larger fish. Mercury accumulates and becomes concentrated in the predatory fish at levels of up to a million times higher than in the water they live in.
- Other wildlife. For fish-eating creatures such as eagles, osprey, loons, turtles, mink and otters, mercury in the diet can cause weight loss, disrupt reproduction, and lead to early death.
- A long-term problem. Once in the environment, mercury persists for a long time and never degrades into a harmless substance.
Because mercury persists for so long, it takes many years for mercury levels in fish to drop significantly. It is important to be aware of and follow fish consumption advisories.
Additional Resources for Environmental Effects of Mercury
Health Effects of Mercury
There are several different forms of mercury. Some are more dangerous than others, but all are toxic.
Depending on type and amount, exposure to mercury can damage a person's nervous system, brain, kidneys, liver, and immune system.
- Methylmercury is extremely poisonous and can damage the brain even at low levels. People may be exposed to this type of mercury by eating contaminated fish.
- Elemental mercury, the silvery liquid found in some thermometers and switches, is most dangerous when inhaled and needs to be handled with care.
Children are most sensitive to mercury exposure, which can irreversibly damage their developing brains and nervous systems.
Women who are pregnant or may become pregnant need to be careful, too, since exposure can happen in the womb if they eat contaminated fish.
Additional Resources for Health Effects of Mercury
Handling Mercury Safely
Learn how to safely manage products and wastes that contain mercury at home, school, and work.
See Key Actions below to use an interactive map or search by location to find nearby collection and recycling sites.
See Additional Resources below to learn more about safe management and disposal of fluorescent bulbs, proper cleanup of broken bulbs and elemental mercury spills, and more.
Additional Resources for Handling Mercury Safely
Mercury Management Act
Signed into law in 2006, amended most recently in 2014, and embodied in M.G.L. Chapter 21H, Sections 6A-6N, the Mercury Management Act:
- Bans the sale of specific products containing mercury;
- Requires some manufacturers to notify the state of products with mercury content;
- Directs schools and state government to stop purchasing mercury-containing items;
- Requires end-of-life recycling for certain mercury-added products;
- Establishes a program for removing mercury switches from vehicles; and
- Prohibits disposal of mercury in trash and wastewater.
See the law and answers to common questions about its mercury product disposal ban provisions in Additional Resources below.
Additional Resources for Mercury Management Act
MassDEP Regulations & Policies
Consistent with Mercury Management Act requirements, MassDEP has implemented regulations that:
- Limit the sale and disposal of mercury-containing products,
- Promote their safe management and recycling, and
- Reduce environmental exposures to mercury.
Even before the 2006 law took effect, MassDEP required power plants to reduce mercury emissions and municipal waste combustion facilities to separate mercury-containing items from the loads of trash sent to them for disposal.
The agency has also issued policies and guidance to help regulated businesses and facilities comply with these rules.
See Additional Resources below to learn more.
Additional Resources for MassDEP Regulations & Policies
Industry Reporting & Compliance
MassDEP reporting and certification requirements prevent mercury releases to the environment by ensuring proper end-of-life management of products that contain mercury.
Under the Mercury Management Act, the agency requires:
- Manufacturers, recyclers, and shredders of vehicles to certify that they are managing vehicle switches and other mercury-containing wastes properly, and
- Manufacturers of certain mercury-containing products to submit for each product sold in Massachusetts:
(1) a notification to the Interstate Mercury Education and Recycling Clearinghouse (IMERC), and
(2) a labeling plan, collection and recycling plan, and annual compliance certification to MassDEP.
Under other statutory authority, MassDEP requires:
- Dental practices and clinics to certify that they are managing and recycling dental amalgam wastes properly, and
- Municipal Waste Combustors to develop and implement plans for diverting mercury-containing products from the waste loads they accept for disposal.
See Key Actions below to learn more.
Additional Resources for Industry Reporting & Compliance
Fish Monitoring & Advisories
MassDEP monitors contaminant levels in the edible tissues of freshwater fish and the Department of Public Health (DPH) issues advisories on eating fish taken from bodies of water across the state.
A fish consumption advisory:
- Warns either the general population or a specific group of people - pregnant and nursing women, or children under the age of seven, for example - not to eat fish or to limit how much they eat.
- Is based on a conservative estimate of how much fish a person can likely eat without experiencing any adverse health effects.
- Addresses one or more certain species of fish taken from a specific local body of water by sport and subsistence fishermen.
Read advisories carefully. Even fish you buy from a store or market can contain mercury. Be sure to buy only from reputable sellers and ask ask about the origin of their catches.
See Key Actions and Additional Resources below for more information.
Additional Resources for Fish Monitoring & Advisories
Massachusetts is not alone in sounding the alarm about mercury and taking concrete steps to reduce its presence in the environment.
At least 40 states, including all six in New England, have found fish with elevated levels of mercury in their lakes and ponds.
Massachusetts, other Northeastern states, and eastern Canadian provinces together have developed and are implementing a regional action plan to reduce mercury in products and the environment.
Specifically, these jurisdictions have:
- Phased out mercury use in certain products, such as batteries,
- Imposed more stringent limits on industrial discharges and emissions, and
- Spurred the development of better pollution control technologies.
As a result, there have been significant reductions in mercury emitted to the air and discharged to streams and lakes over the last couple of decades.
Massachusetts also was a founding member of the Interstate Mercury Education and Reduction Clearinghouse (IMERC), launched in 2001 to provide:
- Ongoing technical and program assistance to states that have enacted mercury education and reduction legislation, and
- A single point of contact for industry and the public to learn about mercury-added products and member states' mercury programs.
Massachusetts is one of 13 IMERC member states. The others are Connecticut, Louisiana, Maine, Michigan, Minnesota, New Hampshire, New Jersey, New York, North Carolina, Rhode Island, Vermont, and Washington.
See Additional Resources below to learn more.