Abstract:
Background Wastewater treatment plant (WWTP) workers are exposed to biological hazards, including bacteria, fungi, and viruses with pathophysiological properties, posing a risk to workers’ health. Due to the complexity of WWTP bioaerosol composition, exposure assessment is challenging, and new methods are needed for a more holistic evaluation. Objectives (1) Characterize bacterial exposure in three Norwegian wastewater treatment plants (WWTPs), (2) Assess the bioaerosol’s and cultivated viruses’ ability to activate toll-like receptors in vitro, and (3) Elucidate adverse health effects in WWTP workers.
Methods:
Inhalable bioaerosol fractions were collected with personal and stationary sampling, and endotoxin levels and 16S rRNA gene as a biomarker for bacteria were quantified. The inflammatory potential of the bioaerosol was assessed in vitro with HEK-Blue reporter cells, and we investigated the applicability of these cells for viral ligand detection by exposing them to cultivated Influenza A virus, Adenovirus F/40, E. coli phage MS2, and bovine Coronavirus. We used self-reported questionnaire data for an observational health assessment.
Results:
TLR2 and TLR4 were activated in 85 and 91% of bioaerosol samples and activation correlated with airborne endotoxin levels. Airborne bacteria were present in all samples, with higher levels in personal (2.7 × 10 4 gc/m 3 ) versus stationary [...]