Background: Exposure to benzene causes several adverse effects, including decreased number of erythrocytes, leucocytes, and red blood cells, and results in aplastic anemia. The aim of this study was to investigate hematological changes due to benzene exposure in painting workers. Methods: This study was conducted on benzene-exposed and nonexposed workers in Tehran, Iran. The study sample included 40 painters exposed to different levels of benzene and 40 unexposed controls in an automobile manufacturing company. Sampling was carried out with an active pump sampler, using the NIOSH method 1501. Varian C-3800 gas chromatography-flame ionization detector (GC-FID) was used for the analysis of 40 benzene samples. Blood samples from 80 workers were collected from both the case and control groups. Hematological indices were analyzed for red blood cell, white blood cell, hematocrit, hemoglobin, platelet, and white cell differential count.

Background: Air pollution have led to severe problem of adverse health effect in the world. This study aimed to conduct the health risk assessment, cancer risk analysis, and non-cancer risk for exposure to volatile organic compounds (VOCs) and hydrogen sulfide (H2S) in petrochemical industry. Methods: In this cross-sectional research, 123 samples were collected in the ambient air in Iran during winter 2016. For sampling and analysis of VOCs and H2S, 3 methods (numbers 1500, 1501, and 6013) presented by the National Institute of Occupational Safety and Health (NIOSH) were used. For determination of risk assessment of chemical pollutants, semi-quantitative method presented by the Occupational Safety and Health Division, Singapore was used. Finally, for calculation of cancer risk analysis, Chronic Daily Intake (CDI) and calculation of non-cancer risk, Exposure Concentration (EC) were used. Results: Average concentration of benzene (2.12±0.95) in breathing zone of workers were higher than the Threshold Limit Values-Time Weighted Average (TLV-TWA) (P<0.05). Among chemical substance, benzene had very high rank of risk in petrochemical industry. Rank of risk for H2S, toluene, and xylene present in the breathing zone of workers was low. The mean cancer risk for workers exposed to benzene was estimated 8.78×10-3, in other words, 8.7 cancer per 1000 i.e. higher than the acceptable standard of 10-6 . In our study, non-cancer risk for BTX was higher than the acceptable standard of 1. Conclusion: In particular, overall cancer and toxic risk can be associated with long term exposure to benzene.

Background: Lead is one of the most widely used metals in the industries and is the amplest metal element on the Earth’s crust. This metal disrupts the physiological processes of the body due to its accumulation in various tissues. The present study aimed to determining the association of lead exposure with blood pressure and blood components of the lead mine employees in Isfahan City, Iran.  Methods: In this cross-sectional study, 187 workers were investigated; they worked in the lead mines of Isfahan from January to April 2016. The staff was divided into two groups: one was exposed to lead and the other was the control group. The participants' general information was collected in worksheets, including age, work experience, work shift, body mass index, blood pressure, and smoking status. Sampling was carried out by active sampling using the NIOSH 7300 method. Blood samples were taken from all participants and their hematological parameters were evaluated, including red blood cell, platelet count, percent of lymphocytes, and volume of red blood cells. Results: The participants' age means were 34.06 (8.8) and 37.04 (11.48) years in the case and control groups, respectively. The time-weighted average concentration of lead in the breathing zone air of workers was 0.0533 mg/m3. The average systolic blood pressure was 12.01 (1.3) mmHg in exposed workers, while it was 11.78 (1.1) mmHg in the control group. The average diastolic blood pressure was 7.84 (0.71) mmHg in exposed workers and 7.73 (0.54) mmHg in control group. Statistical test results showed a significant difference between the case and control groups with regard to their systolic and diastolic blood pressure (P<0.05). Furthermore, no significant difference was observed between the lead-exposed and non-exposed groups with regard to the hematocrit and hemoglobin levels. Conclusion:  According to the results, lead exposure can cause metabolic changes in blood pressure and some of its features. Considering the importance of this issue, some preventive measures should be taken to maintain and improve the worker's health and well-being, such as increasing the workers' rest time, performing periodic examinations for them, as well as conducting safety workshops and training sessions.