A study of the status of exposure to polycyclic aromatic hydrocarbons (PAHs) in relation to its metabolites among workers in a Korean chemical factory / Um estudo sobre o estado de exposição a hidrocarbonetos aromáticos policíclicos (HAPs), em relação aos seus metabolitos, entre os trabalhadores em fábricas de produtos químicos coreana

The study was conducted to evaluate the status of worker exposure to polycyclic aromatic hydrocarbons (PAHs) through the measurement of urinary metabolites such as 1-hydroxypyrene (OHP) and 2-naphthol. A survey using a questionnaire involving 326 workers with measurement of urinary metabolites of 1-OHP and 2-naphthol was conducted. The differences in urinary 1-OHP and 2-naphthol concentrations, and changes in work, smoking habits and lifestyle were analyzed. The number of male subjects was 314 (96.3%), the largest age group was the fifth decade (170 cases, 52.1%). The urinary 1-OHP and 2-naphthol concentrations were significantly higher in the production workers. The urinary 1-OHP and 2-naphthol concentrations were significantly higher in smokers. In a multiple regression model, log (1-OHP) increased in smokers and production workers, while log (2-naphthol) only increased in smokers. Our results suggest that workers in this factory were exposed to PAHs from non-occupational as well as occupational sources. The occupational exposure to PAHs can be reduced through the improvement of the process, but the exposure due to smoking can be prevented only by giving up smoking.

O presente estudo foi realizado para avaliar o estado de exposição a hidrocarbonetos aromáticos policíclicos (HAPs) em trabalhadores, por medição de metabólitos urinários, tais como 1-hidroxipireno (OHP) e 2-naftol. Foi realizada uma pesquisa por questionário envolvendo 326 trabalhadores e a mensuração dos metabólitos urinários de 1-OHP e 2-naftol. Foram analisadas as diferenças na urinária 1-OHP e as concentrações de 2-naftol e mudanças pelo trabalho, hábito de fumar e estilo de vida. O número de indivíduos do sexo masculino foi de 314 (96,3%), a maior faixa etária foi a quinta década (170 casos, 52,1 %). Com relação aos metabólitos urinários 1 -OHP e 2-naftol, as concentrações foram significativamente maiores nos trabalhadores produtivos. As concentrações dos metabólitos urinários 1-OHP e 2-naftol foram significativamente maiores nos fumantes. Em um modelo de regressão múltipla, log (1-OHP) aumentou em fumantes e em trabalhadores produtivos, enquanto que log (2-naftol) aumentou apenas em fumantes. Nossos resultados sugerem que os trabalhadores desta fábrica foram expostos tanto a HAPs de fontes não ocupacionais como ocupacionais. A exposição ocupacional a HAPs pode ser diminuída através da melhoria do processo, mas a exposição devido ao fumo só pode ser impedida interrompendo esse hábito.

1-Hydroxypyrene and interleukin-8 for biological monitoring of vehicle exhaust exposure and effects among gas-station workers

Air pollution encountered in many towns and cities throughout the world is associated with high levels of fuel vapors and motor vehicle-generated exhaust. A consistent association was reported between the levels of particulate matter and semi-volatile organic compounds in the ambient air with increasing mortality and morbidity. Although the epidemiological evidence is strong, there are yet neither established biological mechanisms to explain the toxicity in humans nor biologically established biomarkers for both exposure and severity of disease. This study was done to determine the impact of vehicle exhaust on the human airways among extensively exposed workers in few gas stations. The extent of exposure to polycyclic aromatic hydrocarbons [PAHs] is measured by estimating the level of 1-hydroxypyrene [1-OHP], a pyrene metabolite. Respiratory inflammation is clinically assessed and evaluated using pulmonary function tests. The impact of respired vehicle exhaust on the immunobiology of the respiratory system is evaluated by estimating the level of the cytokine interleukin-8 [IL-8] in serum, being used as an indication for respiratory inflammation and tissue damage. The study population consisted of 34 highway gas-station workers exposed to vehicle exhaust and 30 matched non-exposed office workers. The exposed population was further subdivided into a fueling group [n=22] working in petrol filling of cars and a car washing group [n=12] working in car cleaning. The study population was subjected to thorough clinical examination, pulmonary function testing and laboratory investigations. Measurement of the urinary 1-OHP level was done using the high performance liquid chromatography [HPLC] with electrochemical water detectors. As for the cytokine IL-8, estimation was done using quantitative sandwich enzyme-linked immunosorbent assay [ELISA]. Medical history and clinical examination revealed significantly higher frequency of repeated chest infections among the exposed group [41%] than among the control subjects [6.6%]. As for chronic bronchitis, asthmatic attacks and dyspnea, the results were higher among the exposed groups but with no statistically significant difference. Ventilation function tests revealed the presence of an obstructive affection among exposed workers correlating strongly with age and smoking habits but not with the duration of exposure. The level of FEV[1] /FVC ratio correlated with the level of 1-OHP that is the PAHs biomarker of exposure [r=-0.313; P<0.01]. The urinary 1-OHP was found to be significantly higher among the exposed population, but still no significant correlation was obtained with exposure duration. The serum IL-8 level was markedly elevated among the exposed workers and significantly correlated with FEF[25%-75%] [r = -0.263; P<0.05] revealing the presence of a high risk of chronic inflammation and lung cancer. Occupational exposure of workers in the gas stations to vehicle exhaust carries an increased risk for respiratory diseases such as repeated chest infections, chronic bronchitis and asthmatic attacks as proved by the presence of dyspnea and the decrement in pulmonary functions. Alteration of the immunological responses of the respiratory epithelium should be considered bearing a risk factor for lung cancer development later on in life. Using the urinary 1-OHP level as a biomarker for exposure and the serum IL-8 level for chronic inflammation and respiratory disease severity and progression should be further evaluated. Long-term impact on the environment needs to be properly investigated in addition to the implementation of protective measures aiming at reducing the occupational exposure to diesel-related polycyclic aromatic hydrocarbons