Toxicology and Ecotoxicology
Scientific literature concurs that bismuth and most of its compounds are less toxic compared to other heavy metals (lead, antimony, etc.) and that it is not bioaccumulative. They have low solubilities in the blood, are easily removed with urine, and showed no carcinogenic, mutagenic or teratogenic effects in long-term tests on animals (up to 2 years). Its biological half-life for whole-body retention is 5 days but it can remain in the kidney for years in patients treated with bismuth compounds.
Bismuth poisoning exists and mostly affects the kidney, liver, and bladder. Skin and respiratory irritation can also follow exposure to respective organs. As with lead, overexposure to bismuth can result in the formation of a black deposit on the gingiva, known as a bismuth line.
Bismuth's environmental impacts are not very well known. It is considered that its environmental impact is small, due in part to the low solubility of its compounds. Limited information however means that a close eye should be kept on its impact.
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