Evaluation of Exposure to Toluene and Xylene in Gasoline Station Workers

Abstract

The main volatile organic compounds found at gasoline stations are benzene, toluene, ethylbenzene, and xylene isomers (BTEX). They cause several harmful effects on human health. Regulatory Norm 7 (1978) provides that, in Brazil, biological monitoring of toluene and xylene is carried out by measuring the urinary metabolites hippuric acid (HA) and methylhippuric acid (MHA), respectively. The objective of this study was to assess the exposure to toluene and xylene and to identify related signs and symptoms in gasoline station workers. A cross-sectional epidemiological study was conducted with workers occupationally exposed to fuels. These gasoline station workers were divided into two groups: 94 workers exposed mainly by inhalation (convenience store workers (CSWs)) and 181 workers exposed by inhalation and dermal route (filling station attendants (FSAs)). A comparison group was formed by 119 workers not occupationally exposed to fuels (office workers (OWs)). Workers exposed to fuels had higher average levels of these exposure biomarkers (HA and MHA), which were also higher in convenience store workers than in filling station attendants. In addition, individuals exposed to the solvents present in gasoline had altered mood/depression, cramps, dizziness, drowsiness, headaches, irritability/nervousness, weakness, weight loss, and other symptoms more frequently and had higher urinary levels of HA and MHA compared to the comparison group. Gasoline station workers showed high levels of HA and MHA, reflecting high occupational exposure to the solvents toluene and xylene present in gasoline, demonstrating that changes in the current legislation and in the work environment are necessary to ensure better health protection for these workers.

Assessment of genotoxicity biomarkers in gasoline station attendants due to occupational exposure

“…The levels of VOCs, such as BTEX in fuel vapor, have been measured both in the working environment and in the biological fluids of the gasoline station attendants in various countries, and some of these measured values have exceeded the limit values recommended by American Conference of Governmental Industrial Hygienists (ACGIH) and National Institute for Occupational Safety & Health (NIOSH) (Bahrami et al, 2007; Raghavan and Basavaiah 2005; Scheepers et al, 2019; Soltanpour et al, 2021). Several studies have detected higher levels of metabolites of these hydrocarbons, such as trans trans-muconic acid (t,t-MA), in blood or urine samples of these workers than in controls (Bahrami et al, 2007; Costa et al, 2016; Geraldino et al, 2021; Hassan et al, 2013). On the other hand, chromosomal aberrations, micronuclei, and DNA strand breaks, which are biomarkers of early biological effects, are used to detect a later stage of carcinogenesis than the stage determined by exposure biomarkers mentioned above (Moller, 2006).…”

Presumed Exposure to Chemical Pollutants and Experienced Health Impacts among Warehouse Workers at Logistics Companies: A Cross-Sectional Survey

“…Although no significant correlation was found, trembling of hands, muscle cramps, slurred speech, and unpleasant taste in the mouth were more frequent among warehouse workers. These symptoms can be related to various chemical substances that may occur under these circumstances, such as aromatic organic solvents, volatile residues of fumigants, and other toxic industrial chemicals [ 7 , 9 , 12 , 31 , 32 , 33 ]. Several pesticides and their residues, for instance various fumigants and insecticides, have neurotoxic effects even in low or moderate concentrations, which may be experienced by exposed warehouse workers [ 34 , 35 , 36 , 37 , 38 ].…”

Exposure assessment of wastewater treatment plant employees to BTEX: a biological monitoring approach

“…Recent occupational research using biomonitoring to assess workers' exposure, like in gas station workers 28 , petrochemical plants 29 , 30 , composting plant employees 31 , and traffic police personnel 32 , have been examined. Despite confirming the presence of BTEX compounds in the air of this wastewater treatment plant (WWTP) and as a result of potential exposure of the WWTPs employees to BTEX (Dehghani et al 2021b, Dehghani et al 2018), estimation of the biological levels of BTEX among the employees of WWTP has not been considered so far.…”