Bureau of
Environmental Health
Health Assessment Section
Mercury
Answers to Frequently Asked Health Questions
“To protect and improve the health of all Ohioans”
What is mercury? How does mercury enter the
Mercury is a naturally occurring element found in
environment?
the environment. Mercury is a metal found in three Mercury can enter the water or soil from natural
forms. The three forms of mercury are: ore deposits in rock. Volcanic rock contains
higher levels of mercury. Ohio’s rocks contain
Elemental (also called Metallic Mercury)
low levels of mercury.
Organic
Metallic mercury and inorganic mercury
Inorganic
compounds can enter the air from burning
Mercury combines with other elements, such as coal and the coal mining waste.
chlorine, sulfur or oxygen, to form inorganic mercury When mercury is released in the burning of coal,
compounds or “salts,” which are usually white it will come down in the rain that will then run into
powders or crystals. Mercury also combines with Ohio’s lakes and streams. Microscopic bacteria
carbon to make organic mercury compounds. in the water ingest the mercury and convert it to
methylmercury. The more mercury in the
Elemental or Metallic Mercury is a shiny, silver, environment, the more methylmercury these
odorless, liquid metal. Metallic mercury is small organisms in the water make. Higher levels
the elemental or “pure” form of mercury of methylmercury in the water build up in the
because it is not combined with other tissues of fish. The larger and older fish tend to
elements. It is the common liquid metal have the highest levels of mercury. Note: Ohio
used in thermometers, dental fillings, blood fish advisories suggest limits for eating Ohio’s fish.
pressure cuffs, fluorescent light bulbs, Metallic mercury easily evaporates into the air
barometers, batteries and switches. It when the liquid metal is spilled. The Ohio Mercury
can also be found in some older medicines. Reduction Group is educating Ohio schools to
At room temperature, metallic mercury remove all metallic mercury-containing items
will vaporize and form mercury vapors. from their school grounds.
These mercury vapors do not have a color,
do not have a smell and are harmful to your health. How does mercury get in your body?
Organic Mercury is mercury that combines with By breathing the vapors in the air from a mercury
carbon and hydrogen to make an organic mercury spill. If you drop a mercury thermometer on the
compound. The most common organic mercury ground, it may break and the mercury may
compound is methylmercury. Methylmercury is separate into many small beads and spread
produced by microscopic bacteria that live on the throughout the room. At room temperature,
bottom of lakes and ponds. These bacteria ingest metallic mercury will vaporize. The higher the
the mercury and turn it into temperature, the more vapors will be released.
methylmercury. Higher levels These vapors are colorless, odorless and are
of methylmercury in the water harmful to your health.
build up in the tissue of fish By breathing the smoke, vapors and particles
and can be dangerous. from industries that burn mercury-containing coal.
By eating fish or shellfish contaminated with
Inorganic Mercury is mercury that combines with methylmercury.
other elements such as chlorine, sulfur or oxygen, By the small releases of mercury from dental
to form “salts.” Mercury salts were once used in work and medical treatments.
skin lightening creams and may be present in old By breathing contaminated workplace air or skin
antiseptic creams and ointments. contact. There is an increased risk for dental,
health services, chemical and other industries
that use mercury.
How does mercury affect your health? Has the federal government made
The nervous system is very sensitive to all forms of recommendations to protect human
mercury. Methylmercury and metallic mercury vapors
are more harmful than other forms because more
health?
mercury in these forms reaches the brain. The EPA has set a limit of mercury in drinking water
at 2 parts per billion (2 ppb).
Exposure to high levels of metallic, organic or
inorganic mercury can permanently damage the The Food and Drug Administration (FDA) has set a
brain, kidneys or a developing fetus. Effects on brain maximum permissible level of 1 part of
functioning may result in irritability, shyness, tremors, methylmercury in a million parts of seafood (1 ppm).
changes in vision or hearing and memory problems.
The Occupational Safety and Health Administration
Short-term exposure to high levels of metallic (OSHA) has set limits of 100 µg/m3 (microgram per
mercury vapors may cause effects including lung cubic meter) of organic mercury per cubic meter of
damage, nausea (upset stomach), vomiting, diarrhea, workplace air and 50 µg/m3 of metallic mercury vapor
increases in blood pressure or heart rate, skin for 8-hour shifts and 40- hour work weeks.
rashes and eye irritation.
The Agency for Toxic Substances and Disease
How can families reduce the risk of Registry (ATSDR) has set a guideline of ≤1 µg/m3
exposure to mercury? (microgram per cubic meter) as the acceptable level
Carefully handle and dispose of products that for most residential occupancy, provided no visible
contain mercury such as thermometers or metallic mercury is present.
fluorescent light bulbs (see below health
alert). Reference
Do not vacuum spilled mercury. It will break
The Agency for Toxic
into small beads and vaporize.
Substances and
DO NOT wash any clothing that has come
Disease Registry
into contact with mercury.
(ATSDR)
If a spill occurs, isolate the spill area (close
March, 1999. Toxicological profile for mercury.
off the room), and contact the local health
Atlanta, GA: U.S. Department of Health and Human
department or Ohio EPA for guidance.
Services, Public Health Service.
Teach children not to play with shiny, silver
liquids. Where can I get more information?
Properly dispose of older medicines that
contain mercury. Ohio Department of Health
Pregnant women and children should stay Health Assessment Section
away from rooms where liquid mercury has 246 N. High Street
been used. Columbus, Ohio 43215
Learn about the Ohio fish advisories by Phone: (614) 466-1390
calling (614) 644-2001 or visiting online at: Fax: (614) 466-4556
www.epa.ohio.gov/dsw/fishadvisory/index.aspx / BEH@odh.ohio.gov
Health Alert !! Ohio Environmental Protection Agency (OEPA)
Replace your mercury-containing thermometers Ohio Mercury Reduction Group (OMRG)
and switches and replace them with mercury-free 50 West Town Street, Suite 700
products. Contact your local Ohio EPA District Columbus, Ohio 43215
Office, Solid Waste Management Division to ask 614-644-3469
how you can dispose of your old mercury www.epa.state.oh.us/
thermometers and products that contain mercury.
Revised December 2010