Assessment of PM₁₀ Atmospheric Particle Concentrations and Heavy Metals Levels in the Air of Gorgan City, Iran

Introduction: With increasing industrialization and urbanization, particulate matter (PM₁₀) has become one of the major air pollutants and a critical concern for environmental and public health. Therefore, this study aimed to assess seasonal/annual variations of PM۱۰-bound heavy metals in Gorgan, compare them with WHO/international data, and identify potential sources via correlation analysis. Methods: cross-sectional experimental study was conducted between March ۲۰۲۳ and March ۲۰۲۴ in Gorgan, Golestan province, Iran. Sampling was performed every six days throughout the study period according to the U.S. Environmental Protection Agency (EPA) method. A total of ۵۲ samples were collected to determine PM₁₀ and heavy metals concentrations. Samples were taken from a central urban station using a BGI Omni FT ambient air sampler. Results: Results showed that PM₁₀ concentrations ranged from a minimum of ۲۰.۸۳ μg/m³ in early November to a maximum of ۲۷۷.۷۸ μg/m³ in early February, with a mean ± SD of ۶۹.۳ ± ۴۹.۸۲ μg/m³ across the study period. Seven trace elements were analyzed, and their annual mean concentrations followed the order: Cd PM₁₀ levels in Gorgan slightly exceeded the WHO ۲۴-hour guideline, with more pronounced fluctuations on a monthly scale. Among the heavy metals, Zn, Pb, and Cu exhibited the highest concentrations, peaking during winter.

کلیدواژه ها:

Heavy Metals ، PM₁₀ ، Ambient Air Quality ، Seasonal Variation.