Occupational and community exposures to toxic metals: lead, cadmium, mercury and arsenic.
West J Med 1982 Dec; 137(6):531-539
Environmental exposures to lead (7439921), cadmium (7440439), arsenic (7440382), and mercury (7439976) are reviewed. Toxic metals are ubiquitous environmental contaminants in the industrial society. Absorption of these metals is now common rather than exceptional among residents of the US. Adult exposures are most serious in the workplace. Children are exposed environmentally from multiple sources. Occupational exposure to lead can occur in hundreds of industries. Lead based paint is the major source of high dose lead for children. Airborne lead from automotive and industrial emissions is generally a low dose but prevalent form of exposure. Lead toxicity is evident principally in red blood cells and precursors, nervous system, and kidneys. Symptoms of toxicity are not very specific and diagnosis depends on finding lead in the blood at an elevated concentration. Cadmium is a more common occupational hazard than an environmental contaminant but community exposures are possible. Acute toxicity is usually experienced in the gastrointestinal system. The principal chronic toxic effect is on the kidney. Cadmium has a long biologic half life in humans. Elevated urine cadmium values are indicative of renal damage. Inorganic mercury is almost entirely an industrial toxin. Organic compounds of mercury are used in agriculture and have environmental and occupational impacts. Mercury compounds reacting with sulfhydryl groups inhibit a variety of enzymes. Chronic occupational exposure to mercury produces a recognizable syndrome with neurological symptoms. Human exposure to arsenic may be occupational or environmental. Acute arsenic poisoning is usually associated with ingestion and is centered in the gastrointestinal tract. Chronic arsenic poisoning is associated with skin, nervous system, liver, and other body systems as well as occurrence of cancer. The biological half life of arsenic is brief in humans. Recent data from the National Health and Nutrition Evaluation Survey indicate disturbing lead concentrations in urban dwellers. The author concludes that industrial workers are the subset of the US population with the heaviest body burdens of toxic metals.
Occupational-exposure; Environmental-exposure; Lead-compounds; Cadmium-compounds; Mercury-compounds; Arsenic-compounds; Acute-toxicity; Biological-effects; Physiological-response; Toxic-effects
7439-92-1; 7440-43-9; 7440-38-2; 7439-97-6
Western Journal of Medicine