Disease Number of Workers Percentage

Repeated trauma 276,600 64

Skin disorders 57,900 13

Lung conditions due to toxic exposures 20,300 5

Physical injury 16,600 4

Poisoning 5100 1

Lung disease due to dusts 2900 1

All other illnesses 50,600 12

Total 430,000 100

Data from Levy BS, Wegman DH: Occupational health — an overview. In Levy BS, et al. (eds): Occupational Health. Recognizing and Preventing Work-Related Disease and Injury,

fourth ed. Philadelphia, Lippincott Williams & Wilkins, 2000, p. 3; and Bureau of Labor Statistics, U.S. Department of Labor, www.hls.gov.

byproducts, and metals are commonly detected at hazardous waste sites ( Table 9-2 ). There are currently 11,300 Superfund-designated waste sites in the United States. The potential

human health hazards associated with exposure to chemical mixtures is a major concern.[2]

There is considerable difference in the magnitudes of exposure in the occupational and environmental settings. Occupational exposures affect a defined cohort of workers who are exposed

to chemicals in the range of parts per million (ppm); by contrast, environmental exposures to these same chemicals in the air, water, or hazardous waste sites may be in the parts per billion

(ppb) or parts per trillion (ppt) range. The health effects of such chronic, low-level exposures are unknown.

In the United States, four regulatory agencies determine exposure limits for environmental and occupational hazards: the Environmental Protection Agency, the Food and Drug

Administration (FDA), the Occupational Safety and Health Administration, and the Consumer Products Safety Commission. The Environmental Protection Agency regulates exposure to

pesticides, toxic chemicals, water and air pollutants, and hazardous wastes. The FDA regulates drugs, medical devices, food additives, and cosmetics. The Occupational Safety and Health

Administration mandates that employers (including hospitals and physicians) provide safe working conditions for employees. All other products sold for use in homes, schools, or

recreation are regulated by the Consumer Products Safety Commission.

Physicians should be familiar with current approaches used by regulatory agencies in the United States and be prepared to explain the strengths and limitations of the scientific evidence in

nontechnical terms. Health care providers must be prepared to counsel patients about the primary prevention of disease related to occupational and environmental exposures, taking into

account potential synergistic effects of mixed exposures and individual genetic susceptibility. Prevention of tobacco smoking would prevent 80% to 90% of lung cancers; however, this

objective has been difficult to achieve, especially in teenagers. Strategies for secondary prevention of lung cancer in former or current smokers (e.g., chemoprevention) have been

disappointing so far.[3] Prevention of occupationally

TABLE 9-2-- Common Chemicals at Hazardous Waste Sites

Acetone DDT, DDE, DDD

Aldrin/Dieldrin 1,1 and 1,2-Dichloroethane

Arsenic Lead

Barium Mercury

Benzene Methylene chloride

2-Butanone Nickel

Cadmium Pentachlorophenol

Carbon tetrachloride Polychlorinated biphenyls

Chlordane Tri- and Tetrachloroethylene

Chloroform Toluene

Chromium Vinyl Chloride

Cyanide Zinc

Data from U.S. Environmental Protection Agency, www.epa.gov/superfund/resources/chemicals.htm.

related diseases rests on defining and enforcing safe exposure levels, developing new technologies to reduce industrial exposures, and identifying less toxic substitutes for industrial and

chemical agents. These strategies require a basic understanding of biochemical and molecular mechanisms of toxicity.

Date: 2016-04-22; view: 927