Urban atmospheric microplastic distribution and potential health impact in Dhaka City, Bangladesh

Microplastics (MPs) have emerged as a pervasive environmental pollutant, with urban air pollution serving as a significant reservoir for these particles. In the present study, we assessed the extent of MPs pollution in the atmospheric dust of Dhaka City, the capital of Bangladesh. Ten major locations were selected from which atmospheric dust samples were collected. MPs were extracted, identified, and characterized using optical microscopy, Nile Red staining, Fourier Transform Infrared Spectroscopy (FTIR), and Raman spectroscopy. The results revealed an average MPs concentration of 1007.6 ± 30.02 particles/g, with Fibers (55 %) being the dominant shapes. Polypropylene (PP) and polyethylene (PE) were the most prevalent polymer types, accounting for over 49 % of the identified MPs. The highest MPs concentration was observed in commercial areas, extraordinarily at Farmgate (2632 ± 105.7 particles/g), while the lowest abundance was found in Sadarghat (293 ± 11.14 particles/g), a riverside location. The study identified estimated daily intake of MPs via ingestion (EDI Ingestion ) and inhalation (EDI Inhalation ) for different age groups, where infants were at maximum risk of EDI Ingestion 145 items/kg-BW/day and EDI Inhalation of 384 items/kg-BW/day. These findings highlight the significant role of urban atmospheric dust as a source of MPs and underscore the potential health risks posed by MPs exposure, particularly for vulnerable young populations. The study provides critical insights into MPs’ distribution and human exposure pathways in urban environments, emphasizing the need for targeted interventions to mitigate MPs pollution in rapidly urbanizing cities like Dhaka. • The average microplastic abundance was 1007.6 ± 30.02 particles/g of atmospheric dust sample. • Seven types of polymer were identified. • Infants were at the maximum risk of MPs exposure, both ingestion and inhalation. • SEM-EDS analysis identified trace elements associated with traffic and industrial exhaust.