Applications
Bismuth metal is used in the manufacture of low melting solders and fusible
alloys as well as low toxicity bird shot and fishing sinkers. Certain Bismuth
compounds are also manufactured and used as pharmaceuticals. Industry makes use
of Bismuth compounds as catalysts in manifacturing acrylonitrile, the starting
material for synthetic fibers and rubbers. Bismuth is sometimes used in the
production of shot and shotguns.
Bismuth in the environment
The most important ores of Bismuth are Bismuthimite and bismite. Bismuth occurs
naturally as the metal itself and is found as crystals in the sulphides ores of
Nickel, Cobalt, Silver and Tin. Bismuth is mainly produced as a by-product from
lead and Copper smelting, especially in USA. The chief areas where it is mined
are Bolivia, Peru', Japan, Mexico and Canada, but only to the extent of 3.000
tonnes per year. There is no reliable estimate of how much Bismuth is available
to be mined, but it seems unlikely than there will ever be a shortage of this
metal.
Health effects of Bismuth
Bismuth and its salts can cause kidney damage, although the degree of such
damage is usually mild. Large doses can be fatal. Industrially it is considered
one of the less toxic of the heavy metals. Serious and sometimes fatal poisoning
may occur from the injection of large doses into closed cavities and from
extensive application to burns (in form of soluble Bismuth compounds). It is
stated that the administration of Bismuth should be stopped when gingivitis
appears, for otherwise serious ulceration stomatitis is likely to result. Other
toxic results may develop, such as vague feeling of bodily discomfort, presence
of albumin or other protein substance in the urine, diarrhea, skin reactions and
sometimes serious exodermatitis.
Routes of entry: Inhalation, skin and ingestion.
Acute effects: Inhalation: POISON. May be a nuisance dust causing respiratory
irritation. May cause foul breath, metallic taste and gingivitis. Ingestion:
POISON. May cause nausea, loss of appetite and weight, malaise, albuminuria,
diarrhea, skin reactions, stomatitis, headache, fever, sleeplessness,
depression, rheumatic pain and a black line may form on gums in the mouth due to
deposition of Bismuth sulphide . Skin: May cause irritation. Eyes: May cause
irritation.
Chronic effects: Inhalation: May affect the function of the liver and the
kidneys.
Ingestion: May affect the function of the liver and the kidneys. May cause
anemia, black line may form on gums and ulcerative stomatitis. Skin: May cause
dermatitis. Eyes: No chronic Health effectsrecorded.
Medical conditions generally aggravated by the exposure: Pre-existing skin and
respiratory disorders.
Bismuth is not considered a human carcinogen.
Environmental effects of Bismuth
Bismuth metal is not considered toxic and poses minimum threat to the
environment. Bismuth compounds generally have very low solubility but they
should be handled with care, as there is only limited information on their
effects and fate in the envIronment.