76 Bioaerosol Exposure in Norwegian Waste Sorting

Occupational exposure during handling and sorting of waste has previously been identified as causative agent for occupational disease. New work operations and technological progress facilitate the waste sorting industry with means to reach global sustainability goals, however, generate unknown work-exposure scenarios. Full-shift personal work air samples were collected to investigate levels of infectious and non-infectious microbial components in bioaerosols and to study the potential of organic dust to elicit an immune response in vitro (TLR activation cell model) and in vivo (plasma biomarkers). Large variation in assessed exposure measurements between and within WSP, as well as between seasons was identified. Dust levels were generally below the current Norwegian OEL (5mg/m3), however contained substantial levels of endotoxins, fungal particles, and microbial agents with immunostimulatory potential. Viable microorganisms in the inhalable fraction were dominated by fungi in the genus Aspergillus and bacteria in the genus Bacillus and Staphylococcus. The samples contained a substantial fraction of risk group 2 human pathogens. Thirty per cent of the organic dust samples elicited TLR activation in vitro. Monocyte levels, plasma levels of IL-1RA, IL-18 and TNFα as well as symptom prevalence of respiratory and general symptoms were higher among exposed waste workers compared to an unexposed control group. The present study indicates that Norwegian waste workers are potentially exposed to relatively high levels of microbial agents that may cause adverse health effects in susceptible individuals.