Estimativa da exposição e risco de câncer a compostos carbonílicos e BTEX em postos de gasolina na cidade de Fortaleza-CE

Abstract

The gas stations (GS) are facilities engaged in the activity of retail sale of liquid fuels derived from petroleum, gas and alcohol. This activity is recognized as an important source of emissions of volatile organic compounds (VOCs), among which are the BTEX (benzene, toluene, ethylbenzene and xylenes) and carbonyl compounds (CCs) (formaldehyde and acetaldehyde). These compounds easily inhaled by attendants and users during the process of refueling and exhaust of vehicles, are a danger to human health even at low concentrations. In this study we evaluated the occupational exposure of workers to BTEX and CCs attendants, from the activities of refuelling and combustion of gasoline in three GSs during the dry (September to December/2009) and rainy (February to June/2010) in Fortaleza. The results showed that a direct comparison between the GSs during the rainy and dry seasons, revealed that the station 2 had the highest concentrations of BTEX, followed by the station 3 and station 1. The monthly average concentrations of CCs showed that formaldehyde, acetaldehyde and acrolein, were the major carbonyl detected. The results showed a close relationship (R > 0.845) between the volume of gasoline sold and the concentration of BTEX. The concentration ratio formaldehyde / acetaldehyde showed that vehicle emissions and the burning of fuels predominate in GSs. The probability of cancer risk for men over 30 and 5 years of exposure to benzene and formaldehyde were above the limit established as safe by the USEPA. The same trend was observed for women attendants, because according to the equations of risk, this group is the most sensitive. In this context, training programs and technical solutions must be implemented to reduce occupational hazards to BTEX and CCs in fuel service stations.