Indoor PM_2.5 and Heavy Metal Composition in Blacksmithing Factories: A Pilot Study in Bandung Regency, Indonesia

This study assessed PM_2.5 concentrations and heavy metal composition in blacksmith workshops located in Mekarmaju village, Bandung Regency, Indonesia. The PM_2.5 levels measured across seven workshops showed significantly elevated concentrations, ranging from 166.88 µg/m³ to 513.80 µg/m³, greatly exceeding the indoor air quality recommended by the World Health Organization (WHO). Chemical analysis revealed toxic heavy metals within PM_2.5, including iron (Fe), chromium (Cr), nickel (Ni), manganese (Mn), zinc (Zn), and lead (Pb), with total heavy metal concentrations varying significantly between workshops. The highest concentration was recorded in workshop B (61.8 µg/m³), while the lowest was in workshop F (6.1 µg/m³). These metals are associated with severe health risks such as respiratory and cardiovascular diseases, neurotoxicity, and increased cancer risk with prolonged exposure. Strong correlations between PM_2.5 and metals such as Fe, Cr, and Mn indicate that emissions from metalworking processes are primary sources of indoor pollution. Although this pilot study provides crucial baseline data, limitations such as a short sampling duration and a small sample size suggest the need for further research. Future studies should include long-term, continuous monitoring and detailed chemical speciation to enhance our understanding of occupational health risks.