Iran Occupational Health

  Background and aims: To date, there is not enough information about the toxic effects of dolomite. The purpose of this study was to assess the extent to which digging and excavating workers involved in constructing a dam in Fars province were exposed to dolomite dust and to evaluate the possible effects of this exposure on the prevalence of respiratory symptoms, functional impairments and radiographic abnormalities of the lungs.

  Methods: This cross sectional study was carried out at the constructing site of a dam in Shiraz, south of Iran. The study population consisted of thirty nine male workers with current exposure to dolomite dust and 40 healthy male unexposed employees. To determine the prevalence of respiratory symptoms, respiratory symptoms questionnaire were used. Personal dust samplers were used to assess the exposure concentrations. Additionally, subjects underwent lung function tests and chest X-ray.

  Results: Atmospheric concentrations of dolomite dust exceeded current permissible levels. Exposed workers had significantly higher prevalence rates of respiratory symptoms than their referent counterparts (P<0.05) . Similarly, decrements were noted in most parameters of pulmonary functions of exposed workers, although the difference was only significant for FEV1/FVC ratio (P<0.05) . No significant differences were noted between exposed and referent subjects as far as their chest radiographs were concerned.

  Conclusions: The findings of this study indicate that medium term exposure to very high concentration of dolomite dust is likely to be associated with respiratory symptoms.