Background: Exposure to environmental pollutants which have entered the atmosphere due to human and industrial activities results in harmful and unwanted effects on human health. The undesired effects of air pollution on mental disorders, mortality, and psychological disorders have been proven. Depression is a common mental health problem in today’s societies which impacts the quality of life. The objective of this study was to determine the relation between exposure to air pollution and frequency of depression in Shiraz (Southern Iran).
Methods: Archived documents of 2658 patients diagnosed with major depressive disorder (MDD) from a psychiatric university hospital were reviewed. The concentrations of five air pollutants including CO, NOX, O3, PM10, and NO2 were determined daily in two air quality monitory stations in downtown Shiraz (Imam Hossein Square) and Kazeroon Gate. The data relevant to these five pollutants were gathered every day for 83 months, from 2010 to 2017, and for more precision, the mean values were used. The relationship between the concentration of each pollutant in the air and the number of patients referring to hospital was determined using the Spearman’s correlation coefficient.
Results: There was a direct and significant relationship between all pollutants and the number of hospital admissions in each month (P<0.05) except for CO which did not show a significant relationship with hospital admission due to depression (P>0.05).
Conclusion: The results of this study indicated a positive relationship between air pollution and depression. Of course, to prove this relationship, it is essential to conduct a number of studies with appropriate methodology and design.

Background: There are millions of workers in the world, who engage in activities associated with welding operations but are not classified as full-time metal workers. The present study aimed to determine the activity of acetylcholinesterase (AChE) in blood of laboratory animals exposed to welding fumes.
Methods: Welding fumes were obtained from Kofar Ruwa, Kano by a skilled welder. 130 albino rats were purchased from the Animal Section of Department of Biological Sciences and were divided into 12 groups. They were given doses equivalent to the workers’ real life exposure regimes, and 1 group was selected as control group. They were administered intratracheally following anesthetization once weekly for twelve weeks. The rats were euthanized and serum samples were collected. Then, AChE activity was evaluated spectrophotometrically using ELISA kit (Sunlong Biotech Company).
Results: The mean values of AChE ranged from 23.1 to 25.05 ng/mL with the control having a value of 24.7 ng/mL. Thus, there was a decrease in the values of AChE in the blood of treated groups, which was significantly different from the control (P < 0.05).
Conclusion: Metal welding fumes negatively affected the AChE by reducing its mean values. This implies that welding fumes possesses neurotoxic effects, which can lead to some neurodegenerative diseases.

Background: Extremely low-frequency electromagnetic fields (ELF-EMFs) are generated from indoor electrical appliances and wiring. In 2002, the International Agency for Research on Cancer (IARC) classified ELF magnetic fields as possibly carcinogenic to humans (Group 2B). Therefore, the aim of this study as the first ever study conducted in Tehran was to survey the public exposure to ELF magnetic fields in dwellings, in 2018.
Methods: In this study, 102 houses were selected using convenience sampling method. The magnetic field was measured based on the IEEE std 644-1994 standard using TES-1393 EMF tester. Spot measurements were done in three different rooms including kitchen, living room, and bedroom of each residential.
Results: The average value of measurements taken in dwellings was 0.1 μT. There was a significant difference between total value of magnetic flux density and background level of magnetic flux density among 102 dwellings. There was also a non-significant difference among magnetic fields collected from kitchen, living room, and bedroom. The ELF magnetic fields collected from television and computer in different distances present that MFs decrease rapidly with increasing distance from the source.
Conclusion: According to the statistical analysis, the average value of ELF magnetic field in Tehran, Iran, is the same as the recommended value provided by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).

Background: Heavy metals (HMs) are toxic pollutants whose concentrations in confined spaces might cause severe health impacts. This study aimed to determine the concentration and health risk of As, Cd, Co, Pb, Mn, Ni, and V in indoor household dust in Isfahan during 2022-2023.
Methods: Ninety dust samples were collected from 30 sampling homes. After preparation and acid digestion of the samples in the laboratory, the concentrations of the elements were determined using the ICP-OES method and analyzed statistically.
Results: Except for Pb, the HMs’ mean concentrations were significantly lower than the permissible limit (P < 0.050). The maximum daily exposure through ingestion, inhalation, and dermal contact for children and adults were 66.1 and 79.1 mg/kg/d, respectively, with Pb as the relevant element in both groups. Furthermore, the maximum lifetime daily exposure doses of 8-10 × 26.1 mg/kg/d belonged to Pb. The maximum non-carcinogenic and carcinogenic risk values through direct ingestion, inhalation, and dermal contact were 4.83 × 1-10 and 1.40 × 8-10 for children and 5.23 × 2-10 and 7.91 × 9-10 for adults, which were associated with Pb in both groups.
Conclusion: The results showed that the HMs content in indoor household dust in Isfahan followed a decreasing trend of Pb > Mn > Ni > V > As > Co > Cd. Moreover, direct ingestion followed by dermal contact and inhalation were the most important exposure pathways to the HMs-contaminated dust for both children and adults.

Background: Prolonged consumption of vegetables containing pesticide residues can pose a risk to the health of individuals over time.
Methods: This study aimed to retrieve the studies on the concentration of pesticides such as acetamiprid, chlorpyrifos, and diazinon in cucumber through a systematic review, and then, a meta-analysis focusing on specific subgroups. Finally, the hazard quotient (HQ) was used to assess the non-carcinogenic risk posed to consumers.
Results: The sequence of pesticides according to pooled (mean) concentration was acetamiprid (140.91 μg/kg) > diazinon (59.03 μg/kg) > chlorpyrifos (40.49 μg/kg). Also, the countries were sorted based on the pooled concentration of chlorpyrifos: Spain (180.00 μg/kg) > Egypt (124.90 μg/kg) > Kazakhstan (49.95 μg/kg) > Greece (20.50 μg/kg) > Saudi Arabia (20.00 μg/kg) > Jordan (3.54 μg/kg) > Iran (3.10 μg/kg). The order for diazinon and acetamiprid was Iran (43.20 μg/kg) > Saudi Arabia (33.00 μg/kg) > China (4.60 μg/kg) and Turkey (231.70 μg/kg) > Egypt (220 μg/kg) > Pakistan (100.00 μg/kg) > Kazakhstan (99.34 μg/kg), respectively.
Conclusion: The HQ of acetamiprid, chlorpyrifos, and diazinon was less than 1 for all countries; hence, the consumption of cucumbers containing these pesticides does not pose a non-carcinogenic risk.