IRSST - Institut de recherche Robert-Sauvé en santé et en sécurité du travail

News release

Occupational Exposure to Bioaerosols When Using Biological Degreasing Stations

  • November 07, 2019

Montréal, November 7, 2019 – To clean oily or greasy parts in mechanical maintenance shops, workers use biowashers or biological degreasing stations. The degreasing agents in these washing stations contain bacteria for which no metrological data were available for assessing the occupational risk of exposure through inhalation. To address this lack of data, the researchers monitored five biological degreasing stations for a year, taking 50 mL samples of degreasing fluid every two months and, for comparison purposes, an initial sample of unused degreaser from each station. Using a variety of methods, the researchers counted and identified the bacteria that colonized the degreasers. They detected 60 species of bacteria at concentrations ranging from 3.6 x 104 to 2.6 x 107 CFU/mL in the used fluids, whereas only one species, Bacillus subtilis, was found in the unused fluids.

“Microorganisms, which include bacteria, can be classified into four infectious groups, and the degreaser manufacturers claim that their products are harmless (Risk Group 1). However, analysis of the samples we collected showed that many of the bacteria identified belonged to Risk Group 2, meaning they represent a moderate risk of infection to individuals, but a low risk to the community,” said IRSST microbiologist Geneviève Marchand. “Strict individual hygiene practices, including hand washing before and after using a biowash station, and wearing gloves, are therefore recommended, chiefly to avoid skin contact,” noted Professor Maximilien Debia of the department of environmental and occupational health at the Université de Montréal.

The study also showed that for these same workers who use biowash stations, exposure through the respiratory tract is very low, even when the stations have a blower to dry the degreased parts. The researchers concluded that no respiratory protection is required to ensure worker health and safety.

The study also showed that for these same workers who use biowash stations, exposure through the respiratory tract is very low, even when the stations have a blower to dry the degreased parts. The researchers concluded that no respiratory protection is required to ensure worker health and safety.

Download the results of the study free of charge at https://www.irsst.qc.ca/en/publications-tools/publication/i/100959/. To keep up with research at the IRSST, follow us on the Web, Twitter, Facebook, LinkedIn or YouTube.

-30-

Source
Noémie Boucher
Communications Advisor , IRSST
514-288-1551, extension 206
[email protected]