Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and no longer represents OSHA Policy. It is presented here as historical content, for research and review purposes only.

Occupational Asthma

Asthma is an illness characterized by intermittent breathing difficulty including chest tightness, wheezing, cough and shortness of breath. It is a frequently serious and sometimes fatal condition. An estimated 11 million workers in a wide range of industries and occupations are potentially exposed to at least one of the more than 200 agents known to be associated with the development of occupational asthma. OSHA has few specific standards that have been designed to protect employees from the risk of this disease and little national attention has been devoted to this issue. OSHA is developing an action plan to reduce worker exposure to this hazard but is not initiating rulemaking at this time.

Hazard Description

Occupational factors have been associated with up to 15% of the disabling asthma cases in the United States (1,2). An estimated 11 million American workers are potentially exposed to materials that can produce occupational asthma, including 558,000 workers exposed to grain dust and 1.4 million health care workers potentially exposed to latex products (3).

There are over 200 documented organic and inorganic agents which have been associated with the development of occupational asthma (4,5). These include:

  • high molecular weight organic dusts, and plant and animal proteins such as those associated with grain dust and laboratory animals (for example, guinea pigs and rabbits) and proteins existing in natural rubber latex;
  • low molecular weight reactive chemicals (e.g. diisocyanates and platinum salts);
  • pharmaceuticals that cause sensitizing asthma (e.g. penicillin, psyllium, and cephalosporins);
  • non-sensitizing respiratory tract irritants (e.g. chlorine gas, sulfur dioxide, fire smoke).
Occupations associated with asthma include health care; animal handling; work with grains; bakeries; work with red cedar; laboratory work; snow crab and egg processing; manufacture of detergents containing biological enzymes; work with paints, plastics, and adhesives; work with metal salts; jewelry making; nickel plating; the tanning industry; and soldering (2,4,5).

In some cases the risks are exceptionally high. Baker's asthma for example has been reported in up to 30% of all bakers (6). One study estimates that 17% of hospital staff will have allergic reactions to latex gloves (7). Another study estimates that 2.9% of all nurses and physicians, 5.6% of operating room nurses, and 7.4% of operating physicians will develop a latex allergy (8).

The American College of Allergy, Asthma & Immunology recently concluded that "latex allergy has become a major occupational health problem, which has become epidemic in scope among highly exposed healthcare workers and in others with significant occupational exposure...." The College recommended that government agencies work with industry, workers, professionals and patient groups on a comprehensive control strategy including occupational health guidelines, updated medical device regulations, content labeling, and epidemiologic surveillance. (9)

The prevention and control of occupational asthma requires more than just the establishment of permissible exposure limits (PELs), because some sensitized individuals become symptomatic at extremely low levels. Comprehensive programs designed to prevent sensitization must include engineering controls, personal protective equipment, work practice controls and medical surveillance.

Current Status

OSHA has set PELs for some of the agents associated with occupational asthma including cobalt, nickel, platinum salts and certain isocyanates. However, the vast majority of materials causing asthma at work, including latex products, are unregulated. NIOSH has recommended exposure limits for a small number of these unregulated agents.


Occupational asthma meets the criteria for designation as an OSHA priority. A very high number of workers in a large variety of workplaces are exposed. The health effects are often serious and incidence rates are high in many occupations. There is a strong potential for effective action to reduce the incidence of occupational asthma (10).

  1. Cartier A. Definition and Diagnosis of Occupational Asthma. European Resp Jour 1994; Vol. 7, No.1:153 - 160.
  2. Chan-Yeung M. Occupational Asthma. Chest 1990; Vol. 98, No. 5: 148S - 161S.
  3. NIOSH; National Occupational Exposure Survey; 1981-1983.
  4. Chan-Yeung M, Malo JL. Aetiological Agents in Occupational Asthma. European Resp Jour 1994; Vol. 7, No.2:346 - 371.
  5. Chan-Yeung M, Lam S. State of Art Occupational Asthma. Am Rev Respir Dis 1986; Vol. 133: 686 - 703.
  6. O'Hollaren MI, Bardana EJ, Montanaro A., ed. Occupational Asthma. Hanley and Belfus, Inc., Philadelphia, Pennsylvania, 1992.
  7. Yassin MS, et al. Latex Allergy in Hospital Employees. Ann Allergy Mar 1994; Vol. 72, No. 3:245-9.
  8. Turjanmaa K. Incidence of Immediate Allergy to Latex Gloves in Hospital Personnel. Contact Dermatitis 1987; Vol. 17:270-275.
  9. "Latex Allergy--An Emerging Healthcare Problem," Annals of Allergy, Asthma and Immunology, 75 (1995): 19-21.
  10. Venables KM. Prevention of Occupational Asthma. Eur Respir J 1994; Vol. 7:768-778.

NOTICE: This is an OSHA Archive Document, and no longer represents OSHA Policy. It is presented here as historical content, for research and review purposes only.