Primary prevention of occupational asthma: identifying and controlling exposures to asthma-causing agents

Primary prevention of occupational asthma requires timely identification and regulation of asthma-causing agents.

We examined 39 substances identified as causing allergic occupational asthma in the US to determine the basis for their identification and their regulatory status. We compared them with occupational asthmagens identified and regulated in the UK and Germany.

US regulatory agencies have not established consistent, evidence-based methods to identify and control exposures to substances that cause occupational asthma. Occupational asthmagens are identified primarily by non-regulatory US organizations, and most are not regulated to prevent asthma.

Implementing an evidence-based identification and regulatory process for occupational asthmagens will help to ensure primary prevention of occupational asthma in the US. This should include: establishing consistent identification criteria; publishing a list of occupational asthmagens; collecting use, exposure, and health effects information on asthma-causing substances; requiring medical surveillance and medical removal protection in addition to exposure limits; and stimulating development of safer alternatives.