UC Irvine

Heating processes for the removal of electronic components from waste printed circuit boards (WPCBs) is an important step in the chain of electronic waste recycling, and toxic fumes are generated during the de-soldering process, causing environmental pollution and posing health risks for the workers. This study is aimed to characterize emission and deposition fluxes of respirable particulate matter (PM), and assess exposure of workers to particle-bound polybrominated diphenyl ethers (PBDEs). An electrical low-pressure impactor was used to measure the real-time PM concentrations inside and outside the hood during the WPCBs de-soldering process. The results show that PM mass concentration inside the hood (204 mg/m3) was significantly higher than outside the hood (9.4 mg/m3), representing 95.4% PM removal by the hood. According to the International Commission on Radiological Protection model, the total deposition fluxes of PM in head airways region, tracheobronchial region, and alveolar region were determined as 1930, 74.0, and 123 μg/h, respectively. The deposition flux for coarse particles (2.5-10 μm) in the head airways was the largest (1830 μg/h), accounting for 86.1% of total PM deposited in respiratory system. The ∑8PBDEs concentration in PM10 inside the WPCBs de-soldering workshop was 20,300 pg/m3, and the ∑8PBDEs inhalation exposure for the worker was 1.46 ng/kg/day. This study improves understanding of PM emission mechanisms and provides fundamental data for health assessments during WPCBs de-soldering process.