Cobalt (Co) is a naturally occurring chemical element found in trace amounts in the earth’s crust and meteoric iron. Small amounts of cobalt compounds are found in most rocks, soil, plants, and animals.
The main commercial application of cobalt is in the production of certain high performance metal alloys and super alloys. It is, however, also used as a dye and pigment to produce the attractive, rich cobalt blue color found in ceramics, glass, pottery, porcelain — and children’s products and toys.
Biologically, a minute amount of cobalt is essential to most living beings, including humans. It is an essential component in the production of vitamin B12. But chronic cobalt exposure and ingestion can cause serious health problems even in small doses.
Cobalt compounds have been found to cause congestive heart failure (when once added to Canadian beer in 1966), allergic contact dermatitis, asthma, cancer, and lung disease. There have been no published studies on the effects of long-term cobalt exposure in humans; therefore, most information about its toxicity comes from isolated incidents or workplace exposure for metal workers.
Studies on rodents have shown various cancers, testicular atrophy, and reduced fertility. Cobalt can also accumulate in organs of animals and affect their function.
Cobalt — as cobalt blue — is increasingly used by manufacturers to color children’s clothing, products, and toys. The State of Washington database established as part of its Children’s Safe Product Act currently lists cobalt and cobalt compounds reported by retailers in 1,157 children’s products across 40 categories.
The products listed include: baby bibs, headwear, and shoes from Gap; bath toys, tiaras, and trousers from H&M; shoes, sleepwear, and skirts from Nike; and bibs, bracelets, and dresses from Gymboree. Lego has also reported cobalt in the pigment of some of its plastic blocks. The full list is available from the State of Washington Department of Ecology.
As with most of the 80,000 chemicals used across the manufacturing industries, cobalt and cobalt blue is used with little advance research and study as to the long-term effects to human health. A natural element found in extremely limited combinations and quantities throughout human history is now pervasive and appearing together with other potentially toxic compounds in thousands of items our vulnerable children come in close contact with all day, every day.
Azurite Cobalt Blue Stone Isolated On White image from BigStock