[Cohort mortality study of workers in an automobile foundry factory]

To understand the major causes of death in automobile foundry workers and investigate casting manipulations hazards to health.

A cohort study of 3529 foundry workers registered in one big automobile factory in Shiyan city of China was performed. Standardized mortality ratios (SMRs) were calculated for the main causes of death by using Chinese national mortality rates as reference.

The cohort mortality was traced from 1980 to the end of 2005 with an accumulation of 84 999 person-years, revealed 265 deaths. The results of this study showed that the standardized mortality ratio for all subjects was 0.96 (95% CI: 0.85 approximately 1.08), which was very close to that expected on the basis of the China national mortality rates. The SMR increased with age, the SMR became greater than 1 in all groups of age 50 and higher. The results showed that malignant neoplasm (3.43%), accidents (1.16%), cerebro-vascular diseases (1.08%), cardio-vascular diseases (0.79%) were the first four illnesses that threatened workers' life span. Statistically significant mortality of malignant neoplasm (SMR = 7.87), accidents (SMR = 2.70), cardio-vascular diseases (SMR = 2.68) and digestive diseases (SMR = 2.79) were found in the foundry workers. The relative risk of malignant neoplasm for first line workers to assistant workers was 1.99 (P < 0.05).

The occupational hazards in foundry factory have harmful impact on the workers' health and life span.