Copper is an essential trace element that is vital to life. The human body normally contains copper at a level of about 1.4 to 2.1 mg for each kg of body weight; and since the body can’t synthesize copper, the human diet must supply regular amounts for absorption. The World Health Organization (WHO) suggests that 10-12 mg/day may be the upper safe limit consumption.
The fact that copper is essential to life is well known, but it’s also a toxic metal, and that toxicity, except for the genetic overload diseases, Wilson’s disease and hemochromatosis, is not so well known. Humans can become copper-toxic or copper-deficient, often because of “copper imbalance” (which can include arthritis, fatigue, insomnia, migraine headaches. depression, panic attacks, and attention deficit disorder).
Copper has been used for centuries for disinfection, and has been important around the world in technology, medicine and culture.
Is copper in the environment a health risk?
The answer to this question is complex. Copper is a necessary nutrient and is naturally occurring in the environment in rocks, soil, air, and water. We come into contact with copper from these sources every day but the quantity is usually tiny. Some of that copper, particularly in water, may be absorbed and used by the body. But much of the copper we come into contact with is tightly bound to other compounds rendering it neither useful nor toxic. It is important to remember that the toxicity of a substance is based on how much an organism is exposed to and the duration and route of exposure. Copper is bioaccumulative – there are many studies of copper biosorption by soils, plants and animals. But copper in the environment, (such as that in agricultural runoff, in air and soil near copper processing facilities such as smelters and at hazardous waste sites) binds easily to compounds in soil and water, reducing its bioavailability to humans. On the other hand, many children are born with excessive tissue copper (reason unknown), and one of the ways we are told to balance a copper imbalance is to reduce your exposure to sources of copper!
There are no studies on what this increased copper is doing to the environment. Copper is listed as an EPA Priority pollutant, a CA Air Toxic contaminant, and an EPA Hazardous air pollutant; it is also a Type II Moderate Hazard by the WHO Acute Hazard Ranking. There is NO DATA on its carcinogenity, whether it is a developmental or reproductive toxin or endocrine disruptor or whether it contaminates groundwater.
Today, because of its long use as a disinfectant and because it’s required for good health, many claims are being made about using copper in various products – including fabric. Copper-impregnated fibers have been introduced, which enables the production of anti-bacterial and self-sterilizing fabrics. These copper infused fabrics are marketed to be used in hospital settings to reduce infections, as an aid to help those suffering from asthma and allergies provoked by dust mites, and in socks to prevent athlete’s foot.
These copper impregnated fabrics are said to be safe, pointing to the low sensitivity of human tissue to copper, and because the copper is in a non-soluble form. Yet, that copper is safe because it is in a non soluble form was disproven by at least one study which tried to determine whether total copper or soluble copper was associated with gastrointestinal symptoms. It was found that both copper sulfate (a soluble compound) and copper oxide (insoluble) had comparable effects on these symptoms.