Hematological Changes in Gas Station Workers.

(1) Background: Benzene, toluene, and xylene isomers (BTX) are present in gasoline. Exposure to benzene may lead to the appearance of a series of signs, symptoms, and complications, which are characterized by benzene poisoning, which is an occupational disease. This study evaluated the presence of signs and symptoms related to occupational exposure and whether occupational exposure to BTX is associated with the development of hematological changes. (2) Material and Methods: This cross-sectional epidemiological study included 542 participants, in which 324 were gas station workers (GSWs) and 218 were office workers (OWs) with no occupational exposure to benzene. To characterize the type of exposure (exposed and not exposed), trans,trans-Muconic acid (tt-MA), Hippuric acid (HA), and Methylhippuric acid (MHA) were used as exposure biomarkers. The tt-MA analysis revealed that the GSWs had 0.29 mg/g of urinary creatinine and the OWs had 0.13 mg/g of urinary creatinine. For HA, the GSWs presented 0.49 g/g of creatinine while the OWs presented 0.07. MHA analysis revealed that the GSWs had 1.57 g/g creatinine and the OWs had 0.01 g/g creatinine. Occupation habits and clinical symptoms were collected by questionnaire and blood samples were analyzed for hematological parameters. The persistence of hematological changes was evaluated with three serial blood collections every 15 days followed by laboratory hematological analysis. A descriptive analysis by the Chi-square test method was performed to evaluate the association between occupational exposure to fuels and the occurrence of changes in hematological parameters. (3) Results: In the GSWs, the most described signs and symptoms were somnolence (45.1%), headache (38.3%), dizziness (27.5%), tingling (25.4%), and involuntary movement (25%). Twenty GSWs that presented hematological alterations performed serial collections fifteen days apart. In addition, these workers presented total leukocyte counts above the upper limit and lymphocyte counts close to the lower limit. Leukocytosis and lymphopenia are hematological alterations present in chronic benzene poisoning. (4) Conclusions: The results found an initial change in different hematological parameters routinely used in clinics to evaluate health conditions. These findings reveal the importance of valuing clinical changes, even in the absence of disease, during the health monitoring of gas station workers and other groups that share the same space.

Evaluation of Exposure to Toluene and Xylene in Gasoline Station Workers.

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.

Gasoline-station workers in Brazil: Benzene exposure; Genotoxic and immunotoxic effects.

Chronic exposure to benzene is a risk factor for hematological malignancies. Gasoline-station workers are exposed to benzene in gasoline, via both inhalation and dermal contact (attendants and managers) or inhalation (workers in the on-site convenience stores and offices). We have studied the exposure of these workers to benzene and the resulting genotoxic and immunotoxic effects. Levels of urinary trans, trans-muconic acid were higher among gasoline-station workers than among office workers with no known exposure to benzene (comparison group). Among the exposed workers, we observed statistically significant biological effects, including elevated DNA damage (comet assay); higher frequencies of micronuclei and nuclear buds (CBMN assay); lower levels of T-helper lymphocytes and naive Th lymphocytes; lower CD4 / CD8 ratio; and higher levels of NK cells and memory Th lymphocytes. Both groups of exposed workers (inhalation and inhalation + dermal routes) showed similar genotoxic and immunotoxic effects.

Analysis of Benzene Exposure in Gas Station Workers Using Trans,Trans-Muconic Acid.

In Brazil, gas station workers are occupationally exposed to the benzene present in gasoline. Brazilian law indicates the use of trans,trans-muconic acid(t,t-MA) as a biomarker of benzene exposure. The aim of this study was to evaluate the level of exposure to benzene in gas station workers, through the quantification of t,t-MA present in urine. A total number of 269 gas station workers divided into 179 filling station attendants exposed by inhalation and dermal route and 90 convenience store workers exposed only by inhalation were included. A control group was formed by 100 office workers, without occupational exposure to benzene. The urinary levels of t,t-MA were evaluated by HPLC with a UV detector. Gas station workers showed higher mean values of t,t-MA (0.204 mg/g creatinine; 95% CI 0.170-0.237) than office workers (0.126 mg/g creatinine; 95% CI 0.0817-0.1693). T,t-MA levels were higher in convenience store workers exposed to gasoline only by inhalation (0.221 mg/g creatinine; 95% CI 0.160-0.282), than in those exposed to gasoline by inhalation and dermal route-filling station attendants (0.195 mg/g creatinine; 95% CI 0.155-0.235). Gas station workers with a higher level of t,t-MA had epistaxis. T,t-MA values were higher in the Downtown (0.15 mg/g creatinine) region's workers than in the more affluent South Zone region's workers (0.07 mg/g creatinine). Smoking habits influenced the urinary t,t-MA values, while the frequency of consumption of industrialized and frozen foods showed no influence.

Vigilância sanitária em postos de revenda de combustíveis: aplicação de um modelo para integrar ações e promover a saúde do trabalhador / Health surveillance in gas stations: application of a model to integrate actions and promote worker’s health

Resumo Introdução: o benzeno, composto encontrado na gasolina, é reconhecido como agente cancerígeno e tem sido objeto de controle em âmbito mundial devido aos seus efeitos agudos e crônicos à saúde humana. No Brasil, trabalhadores de postos de revenda de combustíveis (PRC) são expostos ao benzeno durante suas atividades ocupacionais. A Vigilância Sanitária, ao monitorar a exposição dos trabalhadores ao benzeno, pode avaliar os riscos e implementar estratégias para estabelecer um ambiente de trabalho mais seguro. Objetivo: suscitar a discussão sobre as ações da Vigilância Sanitária em postos de combustíveis baseada na aplicação do modelo Força-Motriz/Pressão/Situação/Exposição/Efeito/Ação (FPSEEA). Método: realização de uma ampla revisão da literatura com a finalidade de obter as informações necessárias para construção e desenvolvimento da matriz proposta no modelo. Discussão: foi possível identificar as deficiências existentes nos diferentes níveis institucionais que possuem suas ações voltadas à proteção da saúde do trabalhador e propor ações para avançar na reflexão sobre o modelo de desenvolvimento, modos de produção e exploração de recursos. Também foram identificadas as possíveis ações da Vigilância Sanitária a serem aplicadas no ambiente ocupacional de PRC para eliminação ou redução dos riscos à saúde aos quais os trabalhadores estão expostos.

Abstract Introduction: benzene, a compound found in gasoline, is recognized as a carcinogen, and it has been controlled worldwide because of its acute and chronic effects to human health. In Brazil, gas station (GS) attendants are exposed to benzene during their occupational activities. Health Surveillance, when monitoring the workers’ exposure to benzene, can assess the risks and implement strategies to establish a safer working environment. Objective: to evoke the discussion about Health Surveillance actions in gas stations based on the application of the Driving Force/Pressure/State/Exposure/Effects/Action (DPSEEA) model. Method: we developed the matrix proposed by the DPSEEA model using information from literature review. Discussion: we were able to identify the existing shortcomings in the different institutional levels that have actions directed to workers’ health protection. We also proposed actions for enhancing the discussion on the development model, modes of production, and resources exploitation. We also identified the possible Health Surveillance actions to be applied in the GS occupational environment to eliminate or reduce the health risks to which workers are exposed.