Health risk assessment of particulate matter 2.5 in an academic metallurgy workshop.

Exposure to indoor PM 2.5 is associated with allergies, eye and skin irritation, lung cancer, and cardiopulmonary diseases. To control indoor PM 2.5 and protect the health of occupants, exposure and health studies are necessary. In this study, exposure to PM 2.5 released in an academic metallurgy workshop was assessed and a health risk assessment was conducted for male and female students and technicians. Polycarbonate membrane filters and an active pump operating at a flow rate of 2.5 L/min were used to collect PM 2.5 from Monday to Friday for 3 months (August-October 2020) from 08:00-16:00. PM 2.5 mass concentrations were obtained gravimetrically, and the Multiple-Path Particle Dosimetry model was used to predict the deposition, retention, and clearance of PM 2.5 in the respiratory tract system. The risk of developing carcinogenic and non-carcinogenic effects among students and technicians was determined. The average PM 2.5 mass concentration for August was 32.6 μg/m 3 32.8 μg/m 3 for September, and 32.2 μg/m 3 for October. The head region accounted for the highest deposition fraction (49.02%), followed by the pulmonary (35.75%) and tracheobronchial regions (15.26%). Approximately 0.55 mg of PM 2.5 was still retained in the alveolar region 7 days after exposure. The HQ for male and female students was <1 while that of male and female technicians was >1, suggesting that technicians are at risk of developing non-carcinogenic health effects compared with students. The results showed a risk of developing carcinogenic health effects among male and female technicians (>1 × 10 -5 ); however, there was no excess cancer risk for students (<1 × 10 -6 ). This study highlights the importance of exposure and health studies in academic micro-environments such as metallurgy workshops which are often less researched, and exposure is underestimated. The results also indicated the need to implement control measures to protect the health of the occupants and ensure that the workshop rules are adhered to.