Iranian Journal of

Background and Objective: Air pollution is one of the most important environmental risk factors that exposure to it can cause many acute and chronic effects on human health. Some regions of Iran, especially the western, southern and southeastern provinces of the country, have been affected with dust storm for years. Studies on the frequencies of dusty days in the country show that central pits of Iran and the cities of Zabol and Zahedan have the highest incidence of dusty days. The purpose of this study was to determine the concentration of suspended particles with aerodynamic diameter of 2.5 μm or less (PM_2.5) in various seasons and months during 2019 in Zahedan.
Materials and Methods: In this descriptive-analytical and cross-sectional study samples were typically collected once every 6 days during a 24-hour period as well as on dusty days using an air sampler (PQ200 / BGI) from July 2018 to July 2019.
Results: The results show that the mean concentration of PM_2.5 in Zahedan during this study was 36.86 µg/m³. The maximum and minimum PM_2.5 daily concentrations in the sampling days were also measured as 130.8 and 4.75 µg/m³, respectively.
Conclusion: In conclusion, 88% of samples contained PM_2.5 concentration above the WHO 24-hr air quality guideline level (25 µg/m³), which could be due to the high incidence of summer dust storms. This indicates that particulate matters are a serious health threat to people living in those areas and calls for the implementing measures to tackle the problem.

Background and objective: Given the harmful effects of Ochratoxin A on living organisms—particularly humans—and its potential to cause various severe health outcomes, a systematic review and meta-analysis was conducted to assess the concentration of Ochratoxin A in cocoa and cocoa-based products.
Materials and Methods: After reviewing and searching for keywords including Ochratoxin A, cocoa, and meta-analysis, 17 studies were ultimately selected from an initial pool of 1,482 articles published between 2016 and 2022. The selection was carried out through four screening stages using international databases such as Web of Science, PubMed, and ScienceDirect, as well as search engines like Google Scholar and SID. The results and data were analyzed using meta-analysis methods in STATA version 17.
Results: The average concentration of Ochratoxin A reported in studies from various continents and countries was 2.461 µg/kg. The highest average concentration was observed in the Americas (3.16 µg/kg), while the lowest was reported in Asia (2.13 µg/kg). By publication year, the highest concentration was recorded in 2018 (4.5 µg/kg), and the lowest in 2022 (0.95 µg/kg). Among analytical methods, liquid chromatography–mass spectrometry (LC-MS) reported the highest average concentration of Ochratoxin A, at 3.11 µg/kg.
Conclusion: The concentration of Ochratoxin A has shown a decreasing trend, which may be attributed to the implementation of preventive measures and strategies to inhibit its production or reduce its levels on farms. Additionally, the LC method demonstrated greater detection sensitivity compared to other analytical techniques.