Background: Silver nanoparticles (AgNPs) can accumulate in various organs after oral exposure. The main objective of the current study is to evaluate the renal toxicity induced by AgNPs after repeated oral exposure and to determine the relevant molecular mechanisms. Methods: In this study, 40 male Wistar rats were treated with solutions containing 30, 125, 300, and 700 mg/kg of AgNPs. After 28 days of exposure, histopathological changes were assessed using hematoxylin-eosin (H&E), Masson’s trichrome, and periodic acid-Schiff (PAS) staining. Apoptosis was quantified by TUNEL and immunohistochemistry of caspase-3, and the level of expression of the mRNAs of growth factors was determined using RT-PCR. Results: Histopathologic examination revealed degenerative changes in the glomeruli, loss of tubular architecture, loss of brush border, and interrupted tubular basal laminae. These changes were more noticeable in groups treated with 30 and 125 mg/kg. The collagen intensity increased in the group treated with 30 mg/kg in both the cortex and the medulla. Apoptosis was much more evident in middle-dose groups (i.e., 125 and 300 mg/kg). The results of RT-PCR indicated that Bcl-2 and Bax mRNAs upregulated in the treated groups (p < 0.05). Moreover, the data related to EGF, TNF-α, and TGF-β1 revealed that AgNPs induced significant changes in gene expression in the groups treated with 30 and 700 mg/kg compared to the control group. Conclusion: Our observations showed that AgNPs played a critical role in in vivo renal toxicity.

Background: Pesticides have critical effects on human health. Because of the high amount of pesticides used, individual exposure is almost inevitable. According to the above-mentioned issues, few studies have been done in this area in Iran. Therefore, this study was conducted to evaluate the knowledge, attitude, and practice of pesticides use among farmers in Kabudrahang County, Hamadan Province, Iran. Materials and Methods: This cross-sectional study was conducted in Kabudrahang County. Data were collected from 262 farmer's sprayer, during April to July 2016. Data were collected, using convenience sampling through interviews with the farmers who had spryer during period spraying. Data collection instrument was a questionnaire that included three sections. Content validity ratio and content validity index indicators were used to measure the validity of questionnaire used from. Data were recorded in SPSS version 21.0 (SPSS Inc., Chicago, Illinois) and were analyzed using frequency analysis and Pearson correlation test. Results: Burning eyes and dizziness were the greater symptoms of poisoning with pesticides. Overall, most of them did not have proper knowledge. Many farmers had proper attitudes toward the use of personal protective equipment. However, 37.4% of them reported that the use of personal protective equipment is not easy. The farmers' practice toward the use of the personal protective equipment correlated with their knowledge and attitude (P < 0.001). Conclusion: It is proposed that educational sets consisted of acquaintance with poisons and their applications, storage, and carrying the pesticides, the methods for effective of different individual protection facilities, and utilizing the behavior to reduce the exposure to poisons should be developed and be available to farmers.

Background: Lead toxicity has become a growing health concern in countries such as Iran. However, little information is available on the assessment and evaluation of the health effects of lead exposure in mine workers. Objectives: The present study assessed the occupational exposure to lead and examine the association of blood lead (PbB) levels with hematological and kidney function parameters in mine workers. Methods: In this matched case-control study, the level of PbB was measured in 100 workers (70 exposed and 30 non-exposed), and then its relationship was evaluated with complete blood count (CBC) parameters, zinc protoporphyrin (ZPP), urea, blood creatinine levels, urinary δ-aminolevulinic acid (ALA), coproporphyrin, and creatinine levels. Results: The results showed a linear and significant relationship between the PbB level and B-ZPP, U-ALA, U-coproporphyrin, and U-creatinine levels in states of PbB levels > 20 μg/dL in a time and dose-dependent manner. A significant relationship was observed between the PbB level and the years of occupational exposure to lead and the B-urea level (P-value < 0.03). Conclusions: Chronic occupational exposure to lead decreased hematocrit, RDW-CV, MCV, MCH, and HGB values but did not significantly change RBC counts. Therefore, a regular assessment of routine blood parameters (such as CBC and ZPP) and renal function indices can be effectively used to monitor the toxic effects of lead exposure.

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.