Physicochemical characteristics and health impacts of ultrafine particles emitted from small home appliances equipped with heating coils and brushed motors

Abstract

Indoor air quality has a critical impact on human health due to the presence of indoor air pollutants. Small home appliances equipped with heating coils and brushed motors generate ultrafine particles that directly attack users. In this study, the physicochemical characteristics of ultrafine particles (UFPs) emitted from selected appliances sold in South Korea were investigated using online real-time aerosol instruments and offline analyses. The brushed motor-embedded hair dryers mostly produced nucleation-mode UFPs, while air fryers and toasters generated Aitken mode-size UFPs. In contrast, the two brushless motor-equipped hair dryers showed the lowest particle emission (at least 1.4 times lower) than others. Among the UFPs, distinct particles composed of copper, silver, or titanium were observed. Carbon-containing particles were also found, which could be produced by the incomplete combustion of organics in the inddor air. The MPPD model simulation showed that the mass per unit area of deposited particles in lungs were higher in children than adults. This implies that long exposure to UFPs emitted from small home appliances can cause unexpected health impacts and diseases more in children than adults. Regulation and test protocols for UFP emissions from home appliances are required to achieve clean indoor air quality for human health.