after shying away from highly poisonous Cadmium pigments in the 90s many artists and manufacturers have recently reinstated a more extensive palette of cadmium colours into their work spaces. Due to the very high toxicity, and the difficulty in avoiding exposure, there is anecdotal evidence that some artists are suffering severe and sometimes potentially irreversible health problems as a result of this development.
Cadmium, in its purest form, is a soft silver- white metal that is found naturally in the earth’s crust. However, the most common forms of cadmium found in the environment exist in combinations with other elements. For example, cadmium oxide (a mixture of cadmium and oxygen), cadmium chloride (a combination of cadmium and chlorine), and cadmium sulfide (a mixture of cadmium and sulfur) are commonly found in the environment.
Cadmium doesn’t have a distinct taste or smell.
How can cadmium enter and leave your body?
Cadmium can get into your blood stream by eating and drinking cadmium-contaminated food or water and by breathing cadmium- contaminated air.
How can you be exposed to cadmium?
You can be exposed to cadmium in the work place by breathing cadmium-contaminated air. If you work for a battery manufacturer or work in metal soldering or welding, then workplace exposure to cadmium may be greater.
Exposure can also occur by eating foods containing low levels of cadmium. For most of us, the most common source of exposure to cadmium is mainly through eating food, especially shellfish, liver, and kidney meats.
What are the health effects of exposure to cadmium?
Exposure to cadmium can cause a number of harmful health effects. Eating food or drinking water with high levels of cadmium can severely irritate or bother your stomach and cause vomiting and diarrhea. Breathing high doses of cadmium can irritate and damage the lungs and can cause death.
However, the greatest concern is from exposure to lower doses of cadmium over a long period of time. The lower and long-term exposure to cadmium through air or through diet can cause kidney damage. Although the damage is not life-threatening, it can lead to the formation of kidney stones and affect the skeleton, which can be painful and debilitating. Lung damage has also been observed.
The results of some animal studies show that animals given cadmium-contaminated food and water show high blood pressure, iron-poor blood, liver disease, nerve damage or brain damage. These effects have not been observed in humans.
The U.S. Department of Health and Human Services determined that cadmium and certain cadmium compounds are probable or suspected carcinogens (substances that cause cancer).
What levels of exposure have resulted in harmful health effects?
In general, the amount of cadmium that will cause health problems will vary depending on: (1) the type of exposure (eating or breathing), (2) the duration of the exposure (short- or long- term), and (3) the form of cadmium (pure cadmium or some combination). Studies show that humans can experience lung irritation after breathing as little as 1.0 milligrams per cubic meter of air (mg/m3) of cadmium-contaminated air for a short period of time (less than or equal to 14 days).
Breathing 0.01 mg/m3 of cadmium- contaminated air over the long-term (greater than 14 days) has resulted in chronic lung disease and kidney disease in humans.
Humans that eat or drink cadmium- contaminated food and water for a short period of time (less than 14 days) in amounts of 0.05 milligrams per kilogram of body weight per day (mg/kg/day) can experience stomach irritation. Long-term exposure (greater than 14 days) in amounts of 0.005 mg/kg/day cause relatively little risk of injury to the kidney or other tissues.
Exposure to cadmium through food is typical for most people but is not a major health concern. This is because the cadmium present in the body from our diet is about 0.0004 mg/kg/day. This figure is about ten times lower than the level of cadmium that causes kidney damage from eating contaminated food.
Where can you get more information? Contact your state health or environmental department, or: Agency for Toxic Substances and Disease Registry Division of Toxicology 1600 Clifton Road N.E., E-29 Atlanta, Georgia 30333
The previously proposed ban on cadmium pigments would have eliminated cadmium pigments in artists' paints and stimulated discussion of cadmium in the arts. Although cadmium pigments are suspected carcinogens according to the International Agency for Research on Cancer, the Center for Safety in the Arts believes that brush painting with cadmium pigments can be done safely using simple precautions to prevent accidental ingestion. Although there is legitimate concern about cadmium release into the environment, only small amounts of cadmium pigment are disposed of during brush cleaning.
Most professional artists we have talked to feel there is no adequate substitute for cadmium pigments at present, and very little cadmium pigment is wasted in the painting process. If cadmium pigments are available only as a specialty item for artists' paints, then the price will inevitably increase substantially. This will probably have the effect of restricting cadmium pigments to serious painters and limit its use among hobby painters. However, we would oppose the use of cadmium pigments in schools.
The other major effects of a cadmium ban among artists would be a ban on cadmium-containing silver solders. We have seen a number of cases of chemical pneumonia and kidney damage among jewelers using these low-melting silver solders. In addition, there is evidence that the cadmium oxide fumes can cause lung cancer in humans.