Cardiovascular diseases among foundry workers exposed to carbon monoxide

Area of Science:

• Occupational Health
• Environmental Medicine
• Cardiovascular Epidemiology

Background:

• Foundry work involves significant exposure to carbon monoxide (CO), a known cardiovascular toxin.
• Long-term health consequences of occupational CO exposure require further investigation.

Purpose of the Study:

• To assess the long-term impact of carbon monoxide (CO) exposure on cardiovascular disease (CVD) morbidity and mortality among Finnish foundry workers.
• To investigate the relationship between CO exposure levels and the incidence of hypertension and ischemic heart disease.

Main Methods:

• A cohort study followed 2857 Finnish foundry workers hired between 1950-1972, with a subset of 931 men examined in 1973 and followed until 1987.
• Data on compensated medication for hypertension and mortality from cardiovascular diseases were analyzed in relation to CO exposure categories.
• Age-standardized incidence and mortality rates were calculated and compared between exposed and unexposed groups, with stratification by smoking status.

Main Results:

• Workers exposed to CO exhibited a doubled incidence rate for compensated hypertension (rate ratio [RR] 2.0).
• Iron foundry workers had significantly higher rates of hypertension, especially when exposed to CO and smoking (RR 3.0 for exposed smokers).
• A higher mortality rate from ischemic heart disease was observed in exposed smokers compared to unexposed non-smokers (rate ratio [RR] 3.0).

Conclusions:

• Occupational carbon monoxide (CO) exposure is associated with an increased risk of cardiovascular morbidity, including hypertension.
• The findings suggest that CO exposure contributes to cardiovascular mortality, particularly ischemic heart disease, with a synergistic effect observed in smokers.
• Interventions to reduce CO exposure in foundries are crucial for protecting worker cardiovascular health.