Assessing air quality of the recycled steel industries and associated health risks in a mega port city of Southeast Asia

Abstract Chittagong, the port city of Bangladesh, has become a major hub for the world’s shipbreaking industry, ideally suited for developing shipbreaking yards and recycled steel industries. This study aimed to evaluate the air quality of recycled steel industries in Chittagong. Formaldehyde (HCHO), total volatile organic compounds (TVOC), and Particulate matter (PM2.5, PM10) were investigated from three shipwrecking yards and five sites in the city near the recycled steel industries. The mean concentrations of HCHO ranged from 204.50 to 463.67 µg m-3, TVOC 326.67–2391.33 µg m-3, PM2.5 ranged from 125.17 to 226.67 µg m-3, and PM10 ranged from 162.33 to 276.60 µg m-3 in the air near the recycled steel industries. All these values exceeded the recommended chronic exposure limits. Calculated hazard quotient (HQ) and hazard index (HI) values consistently exceeded threshold limit 1, indicating a high risk of adverse health effects for children and adults due to air pollutant exposure. These findings highlight the urgent need for stricter environmental regulations and enforcement to promote sustainable shipbreaking and recycled steel industries that balance economic benefits with environmental and public health protection in Bangladesh. Graphical Abstract