Occupational exposure to microorganisms for operators of jet-vac trucks

This study examines bioaerosol exposure and associated biomarker levels in combination vacuum-jet truck ("jet-vac") operators servicing the sewer network in Denmark. Personal exposures (n = 42) and end-of-shift serum samples (n = 30) were collected from 28 workers across four exposure groups: "Stormwater," "Wastewater," "Combined," and "Other" (non-sewage related work). Geometric means of bacterial and fungal exposure levels were 938 and 301 colony forming units per cubic meter of air (CFU/m³), respectively. "Stormwater" workers had significantly higher serum amyloid A (SAA) levels than the "Other" group (p = 0.019). SAA was negatively associated with endotoxin exposure (p = 0.014) across exposure groups. Community compositions differed between exposure groups. Micrococcus was the most abundant bacterial genus in the "Other" and "Wastewater" groups, while Bacillus was the most abundant genus in the "Stormwater" and "Combined" group. Five known human pathogens were identified, including Aspergillus fumigatus and Clostridium perfringens. This first study of jet-vac operators highlights the need for further research on bioaerosol exposures in a larger cohort of workers.