Cardiovascular diseases among foundry workers exposed to carbon monoxide.

Abstract

1KOSKELA R-S. Cardiovascular diseases among foundry workers exposed to carbon monoxide. Scand J Work Environ Health 1994;20:286-93. OBJECTIVES -The study investigated long-term effects of carbon monoxide (CO) exposure on foundry workers' morbidity and mortality from cardiovascular diseases. METHODS -The study population comprised a cohort of 2857 men hired in 1950-1972 by 20 Finnish foundries and also 931 men who were still active in 1972, exposed for at least 4.2 years, took part in a health examination in 1973; 653 of the 931 had also been members of the cohort. These groups were followed to the end of 1987. RESULTS -The age-standardized incidence density rate (1011000 person-years) for compensated medication for hypertension was 4.7 for the unexposed workers and 9.4 for those exposed [rate ratio (RR) 2.0, 95% confidence interval (95% CI) 1.28-2.92]; for the iron foundry workers the rates were 4.7 and 9.9 (RR 2.1, 95% CI 1.24-3.38), respectively. During 1950-1987,255 cardiovascular deaths were observed (284 expected according to nationalrates). The observednumber of deaths due to ischemic heart disease was 183 (203 expected). The iron foundry workers' mortality rate for cardiovascular deaths was 99% of the national expected value. No remarkable differences were found between the CO-exposure categories. For the health-examination group, the age-standardized incidence rate for compensated medication for hypertension was 9.1 for the unexposed nonsmokers and 21.4 for the exposed smokers (RR 2.3, 95% CI 0.97-6.35); the difference originated among the iron foundry workers, for whom the rates were 8.1 and 24.0 (RR 3.0, 95% CI 0.96-9.78), respectively. The age-standardized mortality rate (IDIIOOO person-years) was 2.7 for nonsmokers with no or slight CO exposure and 9.2 for exposed smokers (95% CI 1.13-12.11). This difference was mainly caused by ischemic heart disease. CONCLUSIONS -The results indicate that CO exposure increases the risk of cardiovascular morbidity and mortality.

Epidemiologic estimate of the proportion of fatalities related to occupational factors in Finland

“…A Finnish study (202) observed an increased mortality from IHD among foundry workers. The long-term effects of carbon monoxide may aggravate arteriosclerotic disease (203).…”

Prediction of Extravascular Burden of Carbon Monoxide (CO) in the Human Heart

“…In addition, Mb facilitated diffusion probably contributes to tissue oxygenation over a range of O 2 metabolic demand, 5,86 but this effect has not been implemented in the model. The model prediction of lower myocardial blood and tissue O 2 tensions during exercise in the presence of CO supports the observations of increased risk of cardiac injury in a working population exposed to CO. 50,53,77 Concerns and Limitations…”

“…36,62,87 There is also evidence that workers who are chronically exposed to CO have an increased risk for cardiovascular morbidity and mortality. 50,53,77 In our previous modeling studies, Bruce and Bruce 9,10 compared the time courses of carboxymyoglobin (MbCO) and carboxyhemoglobin (HbCO) levels during and after CO exposures in a resting skeletal muscle compartment and in an ''other tissue'' compartment. These previous results 9, 10 demonstrated that the equilibration of CO between vascular and extravascular tissues during CO exposure, as well as the removal of extravascular CO during therapy, occurred over a much longer time scale than did the major changes in the vascular CO content as represented by %HbCO.…”

Mortality from cardiovascular diseases and sudden death in ferroalloy plants

“…From studies in iron foundries and steel works associations have been reported between elevated blood pressure and exposure to heat or carbon monoxide (1 [8][9][10][11][12][13][14][15][16][17][18][19][20]. However, in a Norwegian study among workers in 1 of the FeSiISi-met plants, no difference in blood pressure between heat-and nonheat-exposed workers was revealed (21).…”