Assessment of Cancer and Non-Cancer Health Risks Associated With Exposure to Black Carbon Particles in the Ambient Air of Tehran City; ارزیابی خطر سرطان زایی و غیرسرطان زایی ناشی از مواجهه با ذرات کربن سیاه در هوای آزاد شهر تهران



Sa Attar Somayeh ALIZADEH ; Ar Pardakhti Alireza REZA ; K Ashrafi KHOSROW ; Ms Hassanvand Mohammad SADEGH
Source: Iranian Journal of Health and Environment Published:2025

Abstract

Background and Objective: Black carbon is a byproduct of the incomplete combustion of fossil and biomass fuels. Long-term exposure to black carbon has been linked to an increased risk of lung cancer and cardiovascular diseases. This study aims to evaluate the carcinogenic and non-carcinogenic risks associated with black carbon exposure in the ambient air of Tehran. Materials and Methods: Hourly black carbon concentrations were collected from the air quality monitoring stations operated by Tehran's Air Quality Control Company and averaged to calculate annual means for 2021, 2022, and 2023. The risk assessment for black carbon exposure in Tehran was conducted using the US EPA model. Results: The findings reveal that in Tehran, the carcinogenic risk index (CR) due to black carbon exposure in ambient air is higher for adults than for children. The non-carcinogenic risk quotient (HQ) for both age groups remains below the threshold value of one, indicating a low and negligible non-carcinogenic risk. However, children demonstrate a higher HQ compared to adults. The lifetime cancer risk associated with black carbon exposure is calculated to be 1.4 × 10-3, while the annual cancer risk is estimated at 0.02 × 10-3. Conclusion: The results indicate that the carcinogenic risks associated with black carbon exposure exceed acceptable levels for both adults and children. Adults face a cancer risk six times greater than children, though the non-carcinogenic risk is assessed as low. Reducing black carbon emissions is critical for improving public health in traffic-congested cities, and further research on this topic is strongly recommended. © 2025 Elsevier B.V., All rights reserved.