What is cadmium and how is it used?
Pure cadmium is a soft, silver-white metal found naturally in small quantities in air, water and soil. Cadmium does not have a definite taste or odor. Cadmium is not mined, but it is a byproduct of the smelting of other metals such as zinc, lead and copper. Cadmium is used in nickel-cadmium rechargeable batteries and for metal plating. It also is used in some paints, plastics and metal solders. Some metal containers, such as ice cube trays, pitchers, bowls or ceramic ware can contain small amounts of cadmium. The main industries that use cadmium are metal smelting, electronics, nuclear power, paint pigment production, and other metal working and refining companies.
How does cadmium get into the environment?
Cadmium is found naturally in small quantities in air, water and soil. Since cadmium is a metal, it does not break down and can build up over time. Cadmium can be released into the air when household or industrial waste, coal or oil are burned. Cadmium also can be released from car exhaust, metal processing industries, battery and paint manufacturing, and waste hauling and disposal activities. Once cadmium is in the air, it spreads with the wind and settles onto the soil or surface water as dust.
Higher levels of cadmium may be found in soil or water near industrial areas or hazardous waste sites. High levels of cadmium in surface soils usually result from cadmium particles settling from the air. Soils near roads may contain high levels of cadmium from car exhaust. Surface water also can contain low levels of dissolved cadmium. Cadmium in water tends to sink.
How can I be exposed to cadmium?
Cadmium can enter your body from smoking tobacco, eating and drinking food and water containing cadmium, and inhaling it from the air. Your skin does not easily absorb cadmium so touching cadmium will not likely cause adverse health effects.
Cigarettes contain cadmium, and smokers inhale and ingest cadmium when they smoke. For people who do not smoke, food is the most common source of cadmium. Fruits and vegetables, especially grains, potatoes and leafy vegetables like spinach, grown in soils with high levels of cadmium, may contain elevated levels of cadmium. Shellfish and organ meats, like liver or kidney, often contain more cadmium than other foods.
If a community or home has extremely soft water, small amounts of cadmium may move from metal water lines into drinking water. If you use ceramic ware or cadmium-containing metal containers such as ice cube trays, pitchers or bowls to prepare or store food and drinks, some cadmium may transfer into the food or drinks. Also, hobbyists who make jewelry, or stained glass, or who work with paints containing cadmium may be exposed.
How does cadmium enter the body?
The amount of cadmium that enters the body depends on how a person is exposed. Cadmium does not easily pass through the skin. When you eat food or drink water containing cadmium, only a small amount stays in the body. Poor nutrition may increase how much cadmium stays in your body. If cadmium is inhaled as a gas or fume, it is more likely to stay in your body. Very small cadmium particles may reach the air sacs deep within the lungs. Once in the body, cadmium is stored mainly in the liver, bones and kidneys.
How can cadmium affect my health?
Health effects caused by cadmium depend on how much has entered your body, how long you have been exposed and how your body responds.
Some workers who breathe air with high levels of cadmium over a short period of time may experience lung damage or possibly death. Breathing cadmium in air does not usually cause immediate breathing problems or any warning signs. Therefore, exposure may continue until serious lung damage has occurred. Most naturally-occurring cadmium levels found in the environment are not high enough to cause lung damage. Breathing lower levels of cadmium over several years can result in a buildup of cadmium in the kidneys and lead to kidney disease. It also can cause bones to become weaker. If you eat food or drink water that contains large amounts of cadmium, stomach irritation, vomiting and diarrhea may result.
Women exposed to cadmium in the workplace may have low birth weight babies; however exposure to cadmium at normal environmental levels is not likely to cause low birth weight infants. Rodents exposed to cadmium in air have higher rates of lung cancer, liver damage and changes in the immune system. There is no evidence that cadmium causes cancer at the low levels normally found in the environment.
Is there a test to determine if I’ve been exposed to cadmium?
If you think you have been exposed to high levels of cadmium, you should consult your physician immediately. Cadmium can be measured in blood, urine, hair and nails. Kidney and liver function tests can be done to see if cadmium has damaged them. These tests are often done in combination with other tests, such as a chest X-ray.
How can I reduce my exposure to cadmium?
You need to be aware of the possible sources of cadmium to limit your exposure. Not smoking cigarettes and eating a nutritious diet will help reduce your exposure and prevent adverse health effects. If your drinking water comes from a private well near a source of cadmium, you may want to have the water tested. Public water systems test for cadmium on a regular basis. If you live near a source of cadmium, you may want to have your garden soil tested for cadmium.
Where can I get more information?
This fact sheet was supported in part by funds from the Comprehensive Environmental Response, Compensation, and Liability Act trust fund through a cooperative agreement with the Agency for Toxic Substances and Disease Registry, Public Health Service, U.S. Department of Health and Human Services.