About mercury

Mercury is a toxic metal in the environment. It's liquid at room temperature and easily evaporates into the air, where we can breathe it in. Mercury is one of a  group of pollutants called persistent bio-accumulative toxins, or PBTs. These toxins don't break down or go away, but instead stay in the environment.


Mercury exposure

Mercury exposure is an environmental reportable condition in Colorado under Regulation 6 CCR 1009-7. All laboratories must report all blood and urine test results where mercury levels exceed 0.5 μg/dL (or 5 μg/L) for blood and 20 μg/L for urine, within 30 days of the test. 

Report elevated mercury tests

Mercury and your health

Mercury can harm the central nervous system and kidneys. 

Mercury builds up in the tissue of fish, which people and animals then eat. There is no way to  remove or reduce mercury once it's in fish, even through cooking. Fetuses and young children are at highest risk of health effects from eating mercury in fish, so they, pregnant people, and breastfeeding women have to be especially careful.

This doesn't mean you should stop eating fish. It's a good source of protein and is low in saturated fat. You can still get the benefits of eating fish by using moderation in how much you eat.

Learn how much fish is safe to eat

Although human exposure to mercury occurs most frequently through eating contaminated fish, there are other ways to be exposed to mercury. People have been exposed by inhaling mercury vapors from broken fluorescent lamps, gas regulators, and home fever thermometers. Rarely, people are exposed by swallowing mercury.

Read more about mercury and your health

Questions? Contact ToxCall 303-692-2606 or cdphe_toxcall@state.co.us

Mercury in the environment

Mercury can be released into the environment from natural sources, such as volcanic and geothermal activity, marine environments or forest fires, or it can be released from unnatural sources like coal-fired power plants and other industrial activities.

Recent studies suggest that human activity contributes 50 to 70% of the mercury in the environment globally (Office of Air Quality and Standards Report to Congress, 1997). Once it enters the environment, it circulates in and out of the atmosphere until it ends up in the bottoms of lakes and oceans where it is transformed by bacteria into a form that can accumulate in fish tissue.

Mercury in hospitals

Mercury is used in many instruments and products in the medical setting because of its uniform response to temperature and pressure changes. Mercury is used in sphygmomanometers, laboratory and patient care thermometers, and gastrointestinal devices. Mercury compounds also are used in preservatives, fixatives and reagents. Mercury from medical applications can enter the environment through sewers, spills and land disposal of trash.

Practice Greenhealth is designed to help hospitals improve their environmental performance. Through this program, health care professionals are educated about mercury reduction and pollution prevention opportunities. Practice Green health provides a wide range of tools and technical resources.

Health Care Without Harm and the World Health Organization are advocating for the virtual elimination of mercury-based thermometers and sphygmomanometers and their substitution with accurate, economically viable alternatives.

Instruments and products used in hospitals that may contain mercury

  • Thermometers.
  • Sphygmomanometers.
  • Gastrointestinal tubes.
  • Dental amalgam.
  • Pharmaceutical supplies.
  • Contact lens solutions and other ophthalmic products containing thimerosal, phenylmercuric nitrate.
  • Diuretics with mersalyl and mercury salts.
  • Early pregnancy test kits with mercury-containing preservative.
  • Merbromin/water solution.
  • Nasal spray with thimerosal, phenylmercuric acetate or phenylmercuric nitrate.
  • Vaccines with thimerosal (primarily in haemophilus, hepatitis, rabies, tetanus, influenza, diphtheria and pertussis vaccines).
  • Cleaners and degreasers with mercury-contaminated caustic soda or chlorine.
  • Batteries (medical and non-medical use).
  • Lamps.
  • Electrical equipment.
  • Non-digital thermostats.
  • Pressure gauges.
  • Vacuum gauges.


Disposal options

How mercury from a business is regulated