In the laboratories staffs, there is potential for adverse health effects in exposure to chemicals. Therefore, risk assessment is one of the main issues to prevent these effects. The purpose of this study was to assess the health risk of laboratory staffs and compare the two methods, including ‘Chemical Health Risk Assessment’ (CHRA) and ‘Regional Screening Levels’ (RSLs), that developed by the Department of Occupational Safety and Health of Malaysia and the Environmental Protection Agency respectively. Using these two methods, the places with the highest risk were identified. Comparisons showed that RSLs is a precise method without personal judgment. The CHRA is a simple method for wider chemicals that categorize risk. But CHRA includes fewer parameters compared to RSLs, as well as personal judgment. The results of the present study showed that two methods did not compatible. According to the characteristics of these two methods, it is recommended to use them as a compliment each other to obtain accurate results.

Objective. In different studies, various models have been used for exposure risk assessment of formaldehyde, so this study was conducted to compare existing methods. Method. This cross-sectional analytical study was performed in the pathology section of four hospitals in the west of Iran in 2016. Personal air sampling was performed using National Institute for Occupational Safety and Health (NIOSH) method 3500. Risk assessment with existing methods and comparison between them was performed with the statistical tests. Results. 71% of participants were exposed to values above the threshold limit value. The carcinogenic risk obtained for the staff of the studied hospitals ranged from 3 × 10⁻⁶ to 3.07 × 10⁻⁴. The potential dose of exposure to formaldehyde varied from 73.22 to 3216.06 µg · day⁻¹. The hazard quotient value was more than 1 in 71.4% of cases. Conclusion. The results of the existing methods for carcinogenic risk assessment are almost similar. In general, the Risk Assessment Information System (RAIS) is recommended because of its simplicity and reduction of error probability, saving time and cost. The results of this study can be used as a guide to select the appropriate risk assessment method for planning, providing appropriate control measures and risk management.

Exposure to cypermethrin is common and can lead to acute and chronic health effects. This study aimed to determine the quantitative inhalation risk ofcypermethrinamong the farmers. This cross-sectional study was conducted in nine areas of Shiraz, Iran. Sampling of the respiratory zone was performed by OSHA PV-2063 method using XAD-2 adsorbent andquestionnaire was used to collect the required demographic characteristics and occupational information. Finally, the inhalation risk assessment for exposure to cypermethrin was performed by the Environmental Protection Agency (EPA) method.The mean time-weighted average (TWA) and hazard quotients (HQ) ranged from 0.21 ± 0.1 to 1.68 ± 0.65 and 0.58 ± 0.11 to 1.68 ± 0.46, respectively. 55.6% and 15.2% of the tree spraying and field spraying of the exposed group had HQ more than 1, respectively. Investigation shows that there is no significant relationship between demographic characteristics and HQ values (except height). Exposure frequency (EF), TWA and exposure hour per day had the strongest relationship with HQ.This study showed that the kind of spraying is effective in the amount of risk exposure. The most focus to reduce the health effects associated with inhalation exposure to cypermethrin should be on lowering TWA and exposure hour per day.Due to the high risk of exposure in farmers, it is necessary to identify other effective factors by conducting further studies and presenting their related practical plans.

The present study was performed to identify possible factors affecting the biological monitoring of benzene, toluene, and xylene (BTX) metabolites. Fifty persons with occupational exposure to BTX and 28 administrative employees were evaluated. Urinary trans, trans-muconic acid (t,t-MA), Hippuric Acid (HA) and Methyl Hippuric Acid (MHA) were determined as the biomarkers of exposure. The mean levels of t,t-MA, HA, and MHA in the exposed group were 541.90 (µg‧g creatinine⁻¹), 0.0199, and 0.00205 (g‧g creatinine⁻¹), respectively, which were higher than the non-exposed group (significant difference, P_value <0.001). In the regression model obtained from the amount of urinary t,t-MA, level of education, work experience, residence, length of work per shift, use of personal protective equipment (PPE), and habit of consuming industrial food or fruit juice had a significant effect. HA levels were affected by variables including education level, residence, consumption of industrial food or fruit juice in the past three days, and use of masks, gloves, and PPE. Due to the small amount of MHA in urine, there was a weak correlation between it and independent variables. Based on results, it was concluded that the health effects of exposure to BTX were significantly different between the two groups.