Uses of Bismuth

Bismuth has been used for centuries, although it is often confused with other metals with similar properties, such as tin and lead. Bismuth is one of the first elements known to man, although uses for it have been developing more recently than most others that have been known for a long time. Like water, the solid form is less dense than the liquid, known as a density anomaly.

Uses

Several bismuth compounds have been used medicinally. Some are used for gastrointestinal distress (Pepto-Bismol contains bismuth subsalicylate). Others are used as salves and, in rare cases, for treatment of parasites. In the past, bismuth was also used to treat syphilis and malaria.

Commercially, bismuth is also used in the manufacture of permanent magnets, semiconductors, and thermoelectric materials; as a catalyst in making acrylonitrile; and as an additive to improve the machinability of steels and other metals.
Bismuth is also frequently used in cosmetics, generally nail polish and lipstick.

Environmental Fate

In aerated water, bismuth oxidizes; however, in an anaerobic aqueous environment, bismuth is unaffected. Similarly, in the atmosphere, bismuth is unaffected unless condensation or deposition of water occurs.
Due to the inability for air and water to affect bismuth under most circumstances, bismuth tends to persist until wet or dry deposition, and therefore long-range transport is possible and likely.

Mechanism of Toxicity 

The mechanism by which bismuth produces toxicity has not been identified. Interaction with thiol compounds has been proposed as a primary mechanism.