Analysis and risk estimates to workers of Brazilian granitic industries and sandblasters exposed to respirable crystalline silica and natural radionuclides

Occupational exposure to respirable crystalline silica and to radiation emitted by natural radionuclides present both in rocks and sands was studied in the Brazilian extractive process and granite product manufacture. Respirable airborne dust samples were collected in working environments, where workers perform different tasks with distinct commercial granites types, and also in places where sandblasters work with sands from different origins. The free crystalline silica contents were determined using X-ray diffraction of the respirable particulate fraction of each sample. Dust samples from granite cutting and sandblasting ambient had the natural radionuclides concentrations measured by gamma spectrometry. Dust concentrations in the workplaces were quite variable, reaching values up to 10 times higher than the respirable particle mass threshold limit value (TLV) set by the American Conference for Governmental Industrial Hygienists of 3 mg m(-3). Also the free crystalline silica concentrations were high. reaching values up to 48 times the TLV of 0.025 mg m(-3). Additionally, our results suggest that the risk of radiation-induced cancer in the granite or marble industries is negligible. However, the combined exposure to dust, gamma radiation, and radon daughter products could result in the enhancement of lung cancer risks associated to sandblasting activities. (C) 2010 Elsevier Ltd. All rights reserved.

Improving the Fluorescence Detectability of Polycyclic Aromatic Hydrocarbons for Evaluation of Workplace Environments of Cement Industries Processing Organic Residues

The burning of organic residues and wastes in furnaces of cement industries has been an attractive and lucrative approach to eliminate stocks of these pollutants. There is a potential risk for producing PAH in the workplace of industries burning organic wastes, so that highly sensitive analytical methods are needed for monitoring the air quality of these environments. An official method for determination of PAH is based on liquid chromatography with fluorescence detection at fixed excitation and emission wavelengths. We demonstrate that a suitable choice of these wavelengths, which are changed during the chromatographic run, significantly improves the detectability of PAH in atmosphere and particulate matter collected in cement industries.