Zinc Cas No. 7440-66-6

Zinc

Cas No. 7440-66-6

Potential sources and exposure

Zinc occurs in nature in the 0 and +2 valence states, although it is also found

in four other stable valences. Metallic zinc is insoluble in water, although some

zinc salts are soluble and found naturally in drinking water. Exposure to zinc in

very low concentrations occurs daily through the diet. Average zinc intake

through the diet ranges from 7 to 16.3 mg/day. Zinc is an essential trace element.

Zinc is used in the manufacture of galvanized iron, bronze, white paint, rubber,

glazes, enamel, glass, paper, and as a wood preservative. Exposure to zinc at

higher levels can occur from drinking water or other liquids stored in galvanized

metal containers.

Physical and chemical properties

Property

Value

Molecular weight

65.4 mg/l

Toxicity

Ingestion of excessive amounts of zinc above the recommended daily

allowance for zinc of 15 mg may cause fever and gastrointestinal distress.

Following acute, intermediate, or chronic ingestion of zinc, the primary effects in

humans are pancreatic abnormalities, and gastrointestinal irritation. Ingestion of

zinc has resulted in the reduction of HDL-cholesterol levels in humans. Oral

exposure has been reported to impair immune and inflammatory responses.

Anemia may occur after high-level acute, intermediate, or chronic oral exposure

to zinc.

Inhalation exposure to zinc dust or fumes has been associated with pulmonary

fibrosis and metal fumer fever. Acute high-level exposure to zinc oxide causes

metal fume fever. Zinc oxide penetrates the alveoli, damages the lung tissue, and

transiently impairs respiratory function. Metal fume fever is believed to be the

result of an immune reaction to inhaled oxide particles. Chronic exposure to zinc

has produced anemia. Zinc needs to be present at certain levels to predict

fetal/developmental abnormalities or effects.

There is no evidence to indicate zinc and its compounds are associated with

carcinogenicity in humans (IRIS 1992).

Toxicokinetics

It appears that zinc is absorbed via ingestion and inhalation. Zinc is widely

distributed throughout the body and is found in high concentrations in male

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Appendix D Toxicological Profiles