In this literature review, the epidemiology of work related ischemic heart disease was examined. Research concerning the effect of carbon-monoxide (630080) (CO) on the heart was regarded as important for several reasons, including the large number of workers exposed to CO, the prevalence of CO pollution in the environment, and the scarcity of reports. Based on a review of epidemiological studies, environmental tobacco smoke was implicated in the elevated levels of heart disease observed among nonsmokers. Additional studies indicated that shift work was also detrimental to the health of the heart. Contradictory results were found among studies which investigated the effect of job strain on heart disease. Job strain research was considered problematic, mainly due to the difficulty in measuring psychological strain. Other studies were reviewed, which suggested that both unemployment and the threat of job elimination contributed to the development of heart disease. Heavy physical exertion and exposure to extreme temperatures were related to increased heart disease among workers. Studies relating noise exposure to heart disease were regarded as inconsistent. Research concerning the prevalence of heart disease in specific occupations, such as truck driving, fire fighting, and police work, was viewed as important. In the study of heart disease, the inclusion of such factors as confounders and the healthy worker effect was recommended. The author concludes that more research concerning occupational heart disease is needed, especially considering the scarcity of relevant epidemiological studies and the frequency of the condition.