Indoor air quality is an increasing concern; it causes significant damage to health because it is recycled in confined environments for extended periods of time. Among the pollutants found in these environments, benzene, toluene, ethylbenzene, and xylenes (BTEX) are known for their potential toxic, mutagenic, and carcinogenic effects. This study monitored the BTEX concentrations in paint, carpentry, and varnish workplaces and evaluated the potential to cause adverse health effects on workers in these environments. Twenty samples were collected in workplaces, 20 samples were collected outside the area, and eight samples were taken of the products used. Samples were collected using coconut shell cartridges, and chemical analyses were performed by gas chromatography with mass spectrometry. Toluene presented higher indoor concentrations and indoor and outdoor ratios, indicating that the paint and varnish workplaces had significant BTEX sources. The highest benzene and toluene concentrations were obtained from the paint workshop, and higher concentrations of ethylbenzene and xylenes were obtained in the varnish workshop. The highest non-carcinogenic risks were obtained for m + p-xylenes in the varnish work place, and the second highest non-carcinogenic risk was also determined for the same workshop.

The BTEX group (benzene, toluene, ethyl benzene and xylene) are known for their potential toxic, mutagenic and carcinogenic effects, especially in an indoor occupational environment, where these substances dissipate with greater difficulty. Thus, the present work evaluated the concentrations, mutagenicity and cytotoxicity of the BTEX group in the indoor air of workshops involving painting and varnishing. Samples were collected using air pumps from the outside of the open environment workshops and from the inside of each of the three workshops. The chemical analyses were carried out using gas chromatograph with mass spectrometry. The mutagenic and cytotoxicity potentials were determined using the Salmonella/microsome and WST/LDH assays, respectively. The concentrations of each constituent of the BTEX group were below the limits established by the National Institute for Occupational Safety and Health and toluene presented the highest value. Moreover, these compounds did not induce mutagenic activity in the TA98 and TA100 Salmonella typhimurium strains either in the presence or in the absence of metabolization, and no cytotoxic effects were observed in the A549 human lung cells. These results may be related to the low BTEX values found in the occupational environment, as can be seen in some other studies. Nevertheless, at low concentrations, these compounds may cause toxicity by a pathway not investigated in this study or may have interacted with other non-monitored air constituents, reducing their toxicity. The present study sought to obtain more information and clarifications regarding occupational exposure to BTEX, contributing to the risk assessment of the workers exposed to these substances.