Biological Monitoring of Fuel Stations Workers Occupationally Exposed to Petroleum Products

The increased use of petroleum products in automobiles and industry has led to the deterioration in air quality and human health. Petrol (or gasoline) is a volatile and inflammable petroleum derived liquid mixture primarily used for internal combustion of engines. Occupational exposure to gasoline and air pollutant from vehicular sources are relatively unexplored. The main purpose of this study was conducting biological monitoring for petrol workers occupationally exposed to petroleum product and air pollutants. The study was conducted on fifty male workers employed in petrol filler stations and fifty subjects were recruited as a control group matched for age, sex and socio-economic status. Results revealed that presence of high significant association in the levels of liver enzymes and some haematological changes among exposed workers. In addition to the significant decline in the lung function. A significant increase in urinary phenol as a biomarker of benzene exposure was found. Sulphur dioxide nitrogen dioxide, carbon dioxide and carbon monoxide did not exceed the standards indoor air quality guidelines. However, particulate matter exceeded the limits as indoor air quality guidelines. This study demonstrated that it is possible to detect human health risks at an early stage using sensitive techniques. It is concluded that petrol pump workers should be carefully monitored and should take adequate protective measures to prevent long term effects. INTRODUCTION The increased use of petroleum products in automobiles and industry has led to the deterioration in air quality and human health. These products contain a number of toxins that are considered to be carcinogenic to humans.(1) In filling stations, the volume of fuel dispensed as well as the ambient temperature contributes significantly to the increased emission of volatile hydrocarbons. Benzene (BZ) could be considered to be the most hazardous; xylene (XYL) and toluene (TOL) have toxicities (acute central nervous system effects) in line with other aromatics of lower/different concern than BZ.(2) 587 Bull High Inst Public Health Vol.40 No.3 [2010] Several studies to determine the concentrations of benzene, toluene, and xylene (BTX) in the ambient air of occupational sites have shown increased levels.(3) Petrol filling workers are exposed to a mixture of hydrocarbons in fuel vapours during dispensing fuel and to the gases from vehicular exhaust. The rapidly multiplying number of automobiles in most towns and cities and the corresponding increase in air pollution is a cause of grave concern. Certain groups, by virtue of their occupation, face an increasing threat of its adverse health effects.(4) In addition to automobile exhaust fumes, these workers are also at a risk of inhaling fuel vapour. The combined effects of the two may result in accelerated decline of lung function. Fuel handlers as well as personnel working in close proximity to fuel exhaust such as vehicle mechanics.(4) Petrol (or gasoline) is a volatile and inflammable petroleum derived liquid mixture primarily used for internal combustion of engines. It consists of hydrocarbons (aromatic, saturated and unsaturated) and non-hydrocarbons (N,S, O 2 , vanadium and nickel).(5) Components of car-exhaust as a result of internal combustion of petrol, which are harmful, are CO 2 , NO 2 , SO 2 , benzene, formaldehyde and polycyclic hydrocarbons. These substances are known to produce harmful effects on the blood, bone marrow, respiratory system, lymph nodes, pregnancy and pregnancy outcomes. They also interact with the immune system to cause local and systemic responses ranging from overactive immune responses to immunosuppresion.(5) Atmospheric concentration of gasoline vapor (approximately 2000 ppm) is not safe when inhaled even for a brief period of time (seconds). During fuelling of vehicles, the concentration of gasoline vapor in the air is between 20 and 200 ppm.(6) Health effects of occupational exposure ElSaid & El Noueam 588 to gasoline and air pollution from vehicular sources are relatively unexplored among petrol filling workers. Neglect of ventilation in the work place or failure to use personal protective equipment when using petrol containing solvents like benzene will increase the incidence of toxic effects of benzene in humans, which includes haematotoxicity, immunotoxicity, neurotoxicity and carcinogenicity. (7) Air pollutants and chemicals with known adverse effects like Benzene, Lead, other heavy metals, and Carbon monoxide (CO) and their metabolites can cause adverse health effects by interacting with molecules crucial to the biochemical or physiological processes of the human body. All these have been found to lead to deleterious effect on respiratory, endocrine and haematopoietic systems. High ambient air concentrations of solvents and pollutants had well defined and marked systemic pulmonary inflammatory response with decreased forced vital capacity(FVC), forced expiratory volume in the first second (FEV1), Inspiratory and expiratory flow rates .(8) The main purpose of this study was conducting biological monitoring for petrol workers occupationally exposed to petroleum product and air pollutants. MATERIAL AND METHODS Subjects The present study included 50 petrol filling workers occupationally exposed to petroleum product and air pollutants for more than 5 years as workers group , and 50 subjects selected from administrative departments never occupationally exposed to petroleum product as control group. Verbal consent, approval of the Ethical committee was obtained. All participants signed individual consents prior to the study, occupational and medical questionnaire were completed with the workers through personal interview. Collection and Assay: Blood samples were collected from all cases by sterile disposable syringes. Samples were left to 589 Bull High Inst Public Health Vol.40 No.3 [2010] clot and centrifuged, the separated serum was used for estimation of Serum aminotransferases (ALT and AST) by using Beckman’s autoanalyser.(9) Spot urine samples were collected from all subjects for analysis of urinary phenol as described by Van Roosmalen, et al.(10) The rest of EDTA blood were used to measure complete blood picture (CBC) according to Standard methods.(11) Ventilatory Function Tests: Spirometric measurements were performed in sitting position using a portable spirometer, according to the criteria of the American Thoracic Society (1995).(12) All ventilatory function parameters in the form of forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR) and forced expiratory flow (FEF25-75) were expressed as percent of the predicted value for each person after adjustment for age, gender, race, height and weight. Environmental monitoring of air pollutants such as carbon monoxide (CO), Carbon dioxide (CO2),nitrogen dioxide (NO2), Sulphur dioxide(SO2) and particulate Matter (PM10) were measured using direct reading instrument applying infrared analyzer principal.(13,14 ) Statistical Analysis: The collected data and the laboratory results were computerized. Statistical analysis was done through SPSS version 17.0. The quantitative results were expressed as means ± standard deviation (SD), and Independent t-test, Pearson's correlation coefficient and ANOVA were used in the analysis of the results. RESULTS AND DISCUSSION Data of characterization of the subjects studied revealed that all parameters as age and smoking were not significant. The only significant association in the levels of BMI ElSaid & El Noueam 590 Table 1: Characterization of the subjects


INTRODUCTION
The increased use of petroleum products in automobiles and industry has led to the deterioration in air quality and human health.These products contain a number of toxins that are considered to be carcinogenic to humans. (1) filling stations, the volume of fuel O 2 , vanadium and nickel). (5)mponents of car-exhaust as a result of internal combustion of petrol, which are harmful, are CO 2 , NO 2 , SO 2 , benzene, formaldehyde and polycyclic hydrocarbons.
These substances are known to produce harmful effects on the blood, bone marrow, respiratory system, lymph nodes, pregnancy and pregnancy outcomes.They also interact with the immune system to cause local and systemic responses ranging from overactive immune responses to immunosuppresion. (5)mospheric concentration of gasoline vapor (approximately 2000 ppm) is not safe when inhaled even for a brief period of time (seconds).During fuelling of vehicles, the concentration of gasoline vapor in the air is between 20 and 200 ppm. (6)alth effects of occupational exposure and carcinogenicity. (7)r pollutants and chemicals with known adverse effects like Benzene, Lead, other heavy metals, and Carbon monoxide (CO) and their metabolites can cause adverse health effects by interacting with molecules crucial to the biochemical or physiological processes of the human body.All these have been found to lead to deleterious effect on respiratory, endocrine and haematopoietic systems.High ambient air concentrations of solvents and pollutants had well defined and marked systemic pulmonary inflammatory response with decreased forced vital capacity(FVC), forced expiratory volume in the first second (FEV1), Inspiratory and expiratory flow rates . (8)e main purpose of this study was conducting biological monitoring for petrol workers occupationally exposed to petroleum product and air pollutants.

Subjects
The present study included 50 petrol Beckman's autoanalyser. (9)ot urine samples were collected from all subjects for analysis of urinary phenol as described by Van Roosmalen, et al. (10) The rest of EDTA blood were used to measure complete blood picture (CBC) according to Standard methods. (11)ntilatory Function Tests: Spirometric measurements were performed in sitting position using a portable spirometer, according to the criteria of the American Thoracic Society (1995). (12)All ventilatory were measured using direct reading instrument applying infrared analyzer principal. (13,14 )atistical Analysis: The collected data and the laboratory results were computerized.
Statistical analysis was done through SPSS version 17.0.The quantitative results were expressed as means ± standard deviation (SD), and Independent t-test, Pearson's correlation coefficient and ANOVA were used in the analysis of the results.

RESULTS AND DISCUSSION
Data of characterization of the subjects studied revealed that all parameters as age and smoking were not significant.The only significant association in the levels of BMI  (15) .The other liver enzyme AST is associated with liver parenchymal cells.It is raised in acute liver damage and is also present in red cells and cardiac muscle.Since AST is not specific for the assessment of liver function, slightly raised AST in petrol attendants might be due to gradual lyses of red blood cells. (15)Results (table 3) of Liver function revealed that significant higher levels of ALT and AST among petrol filler workers, similar results were in others studies. (16,17)were being reported in tunnel and bridge workers, traffic wardens and shopkeepers.
Smoking has been reported to accelerate the decline in FEV1. (18,19)ble 5 shows that FVC and FEV1 in petrol stations workers were decreased compared to the control subjects; but without significant difference.While PEFR, FEV1/FVC and FEF25-75 smokers were significantly decreased compared to the controls.Additionally, FEF25-75 of nonsmoker workers was significantly decreased compared to that of the nonsmoker controls.
dispensed as well as the ambient temperature contributes significantly to the increased emission of volatile hydrocarbons.Benzene (BZ) could be considered to be the most hazardous; xylene (XYL) and toluene (TOL) have toxicities (acute central nervous system effects) in line with other aromatics of lower/different concern than BZ. (2)Bull High Inst Public Health Vol.40 No.3 [2010] Several studies to determine the concentrations of benzene, toluene, and xylene (BTX) in the ambient air of occupational sites have shown increased levels. (3)Petrol filling workers are exposed to a mixture of hydrocarbons in fuel vapours during dispensing fuel and to the gases from vehicular exhaust.The rapidly multiplying number of automobiles in most towns and cities and the corresponding increase in air pollution is a cause of grave concern.Certain groups, by virtue of their occupation, face an increasing threat of its adverse health effects. (4)In addition to automobile exhaust fumes, these workers are also at a risk of inhaling fuel vapour.The combined effects of the two may result in accelerated decline of lung function.Fuel handlers as well as personnel working in close proximity to fuel exhaust such as vehicle mechanics. (4)Petrol (or gasoline) is a volatile and inflammable petroleum derived liquid mixture primarily used for internal combustion of engines.It consists of hydrocarbons (aromatic, saturated and unsaturated) and non-hydrocarbons (N,S,

El
air pollution from vehicular sources are relatively unexplored among petrol filling workers.Neglect of ventilation in the work place or failure to use personal protective equipment when using petrol containing solvents like benzene will increase the incidence of toxic effects of benzene in humans, which includes haematotoxicity, immunotoxicity, neurotoxicity filling workers occupationally exposed to petroleum product and air pollutants for more than 5 years as workers group , and 50 subjects selected from administrative departments never occupationally exposed to petroleum product as control group.Verbal consent, approval of the Ethical committee was obtained.All participants signed individual consents prior to the study, occupational and medical questionnaire were completed with the workers through personal interview.Collection and Assay: Blood samples were collected from all cases by sterile disposable syringes.Samples were left to Bull High Inst Public Health Vol.40 No.3 [2010] clot and centrifuged, the separated serum was used for estimation of Serum aminotransferases (ALT and AST) by using function parameters in the form of forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEFR) and forced expiratory flow (FEF25-75) were expressed as percent of the predicted value for each person after adjustment for age, gender, race, height and weight.Environmental monitoring of air pollutants such as carbon monoxide (CO), Carbon dioxide (CO2),nitrogen dioxide (NO2), Sulphur dioxide(SO2) and particulate Matter (PM10) pollutants (Table 4) did not exceed the Egyptian standards except for PM which exceeded the standards and these might be due to working in open areas.Most of the petrol filling stations were situated near to the heavy traffic; workers were prone to exposure to CO.The ambient air concentration of CO was maximum during the peak working hours (6AM -2PM), meaning that workers were exposed to high levels of CO along with other air pollutants and solvents.Particulate matter of the size of 2.5 m and 10m (PM10, PM2.5) and NO2 have been found to be significantly associated with reduced FVC.Similar effects of automobile exhausts on the FVC and FEV1