![[ Visit Client Website ]](images/banner.png)
In Mexico, frequency records of workers’ neoplasms are not available. Although some authors declare that occupational exposures represent 1 to 8% of total neoplasms; in our country, according to statistics from IMSS, there is not a single case of lung occupational cancer reported, at least in five years. The aim of this study was to assess the risk of lung cancer related to occupational exposure to chemical agents in workers affiliated to IMSS.
Methods
In a case-control study, 90 cases and 89 controls, recruited from 2 high specialty hospitals, were interviewed. Cases were workers with histologically confirmed lung cancer; controls were healthy workers who were selected randomly from IMSS’ affiliated population registries. Exposure was estimated by self-reports and by a job-task exposure matrix. The exposures considered were polycyclic aromatic hydrocarbons (PAH’s), pesticides, heavy metals and inorganic particles in four different periods: 5, 10, 15 and more than 15 years previous to diagnosis. Odds ratios were calculated with logistic regression analysis and adjusted for sex, age, smoking, family history of cancer, and education level.
Results
Elevated OR’s for PAH’s in all periods (4.01, 95% CI 1.83, 8.77; 3.75, 95% CI 1.68, 8.36; 4.19, 95% CI 1.73, 10.12; 13.01, 95% CI 4.89, 34.62 respectively), heavy metals in the first and fourth periods (15.00, 95% CI 1.85, 121.87; 4.94, 95% CI 1.40, 17.50 respectively) and inorganic particles in the fourth period (3.41, 95% CI 1.10, 10.60) were found. However, after adjusting for confounding variables, only the exposure to PAH’s in the first period remained significantly associated with lung cancer (OR = 13.7; 95% CI 2.9, 64.2).
Discussion
This study has shown a significant excess risk of lung cancer among workers exposed to PAH’s five years previous to diagnosis. Some of our hypotheses were not confirmed, possibly because of exposure misclassification or low statistical power.