Characterization and Evaluation of Dust on Building Construction Sites in Brazil

Airborne dust can be hazardous to workers' health, especially when polymorphic crystalline forms of silica are present, which, depending on their concentration, specificity, and exposure time, can cause respiratory illnesses. In the majority of cases, the presence of some types of dust on building construction sites can be verified visually or through their effects, such as allergic reactions in workers and residents who live nearby. Construction workers are exposed to many raw materials and production processes that produce diverse types of dust, which propagate through the work envi- ronment and the neighborhood surrounding the construction site. The objective of this study was to quantitatively assess the exposure to dust of construction workers in Brazil, a country considered to be representative of the developing world and emerging economies. A preliminary study, conducted at several building sites to identify hazards, consisted of a sur- vey of dust-generating construction materials, processes, and equipment. Nine activities that expose workers to dust were identified, of which six were chosen for further analytical study: mortar/concrete mixing, worksite cleaning, tile cutting, plastering, woodcutting, and wall/ceiling surface sanding for paintwork. The first three activities were analyzed for the presence of free crystalline silica in the total and respirable fractions; of these, the tile-cutting activity presented the high- est exposure to silica concentration. Of the other three activities, paintwork and woodcutting exhibited total dust expo- sures equaling 368% and 159% of the international recommended limits, respectively. This study presents relevant infor- mation to help fight dust exposure on building construction sites and support the need to conduct quantitative dust analy- ses for workers in this sector in order to determine effective protection measurements.