Respiratory impairment in Brazilian foundry workers exposed to sand

Foundries date back to the 16th century in Brazil and still constitute a strong economic activity today. Workers are at risk of respiratory diseases due to various exposures such as polycyclic aromatic hydrocarbons, pyrolysis degradation products, mineral dust, organic dust, resin, and isocyanates. We evaluate respiratory morbidity among workers in foundries using sand.

Six foundries with sand molding operations were selected. Length of exposure in years was utilized as a surrogate for exposure. The medical evaluation consisted of a respiratory symptoms questionnaire, occupational history, spirometry, and chest X-rays. Additionally, workers exposed to resins and a control group underwent bronchial provocation tests.

A sample of 598 male workers with a mean age of 36.5 years (SD = 10.0) was analyzed. The mean length of exposure was 10.1 years (SD = 7.4). The overall prevalence of pneumoconiosis was 4.5%. Chronic bronchitis (CB) and X-ray profusion were significantly related to the quartiles of length of exposure (trend tests: P = 0.0055 and P < 0.001, respectively). There was a significant risk of having an abnormal FVC and FEV(1) with the presence of pneumoconiosis (OR = 4.63 CI 1.40-13-23, OR 3.34 CI 1.03-9.26, respectively). Workers exposed to resins compared with controls showed no differences in relation to spirometry, respiratory symptoms and bronchial reactivity.

There were significant associations between length of exposure CB and prevalence of profusion 1/0 or above. There was also a significant association for pneumoconiosis versus and abnormal FVC and FEV(1). Foundry workers currently exposed to resins did not show an excess of respiratory symptoms, abnormal spirometry or increased bronchial reactivity.