|Monthly Tech-Tip |
With limited exposure copper is considered relatively safe to use. However when added to low lead solubility glazes copper causes the solubility of the lead to be greatly increased. Solubility of glazes of other types can also be increased by the presence of copper.
OSHA does not consider copper exposure in the workplace to be a significant problem. At worst, they state that copper is an irritant especially airborne.
Copper has a TLV (threshold limit value) of 1.0 milligrams per cubic meter of air breathed. By comparison iron oxide is considered a safe-to-use material at 5.0, kaolin is 2.0, barium carbonate is 0.5, quartz is 0.1-0.05.
Copper is not as toxic by ingestion as many of the other metals (it is not a heavy metal). The standard for water is 1.3 mg/L based more on its effects on taste than toxicity (cadmium is 0.005 mg/L).
Volatile copper given off during certain firing techniques can cause copper metal fume fever. If the exposure is limited, this is a temporary condition that goes away by itself.
People suffering from Wilson039;s Disease must be very careful of copper intake because their bodies cannot excrete it, thus it can build up to dangerous levels. Zinc and vitamin C cause the body to excrete copper and taking megadoses of these products could result in copper deficiency.
Copper has several roles in the body one of which is to keep the connective tissues intact. Copper plays an essential role in the production of elastin which is what keeps our skin soft and supple and wrinkle free. Estrogen increases the amount of copper your body can absorb. The US RDA for copper is 3mg (although figures vary quite a bit). For someone with depleted copper, a daily dosage of 10 mg for a period of one month is not considered unsafe. Copper deficiency can increase LDL cholesterol and decrease HDL. It also has an effect on glucose levels. It is believed that some 90 percent of Americans are copper deficient.
|By Tony Hansen|
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