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Study examines role of 'QACs' in occupational asthma

Healthcare worker getting exposed to QACs in the workplace
A new study confirms a link between specific chemicals commonly found in disinfectants and cleaning products with an increased risk of developing asthma.

Quaternary ammonium compounds or ‘QACs’, long suspected of inducing occupational asthma, are the focus of this latest research.

A growing body of existing research has found exposure to cleaning and disinfecting products is associated with an increased risk of asthma and chronic obstructive pulmonary disease. Specific studies have identified an increased risk among nurses.

Heightened cleaning and disinfecting during the pandemic have directly and indirectly exposed more workers to the toxic chemicals used to kill the virus that causes COVID-19. Given the risk of transmission from contaminated surfaces or objects is considered low, workplaces will want to revisit these practices and also implement the use of safer cleaning productsProper training of joint health and safety committees, worker health and safety reps, workers and supervisors can help too.

Affected workers, more than cleaners

For this study, a team of European researchers, part of an important network studying occupational asthma, set out to examine how quaternary ammonium compounds (QACs) contribute to occupational asthma.

Researchers conducted a retrospective, observational study using data on 871 individuals collected between 2006 and 2018 who had a positive bronchoprovocation test (BPT) when exposed to occupational agents. The test assesses the reaction or response of the lungs when inhaling substances known to cause asthma. Researchers identified 55 of the 871 individuals who had tested positive for asthma and were also exposed to cleaning agents. Using safety data sheets, they honed in on cleaning products known to be potential respiratory sensitizers. Study participants were grouped according to their exposure to lung sensitizers.

From their analysis researchers concluded, “…. exposure to QACs should be considered a potential cause of sensitizer-induced occupational asthma among workers involved in cleaning and disinfection tasks.” Specifically, they found the following.
  • Forty per cent of those who had workplace exposures to cleaning products (22/55) were found to have QAC-induced asthma, having ruled out exposure to other respiratory sensitizers.
  • The QAC’s most associated with positive BPT results were didecyldimethylammonium chloride and benzalkonium chloride.
  • Most of the study participants who developed QAC-induced asthma worked in health care environments (63.6 per cent). The majority were cleaners and nurses but also included a technologist and a dental assistant.
  • Two workers with QAC-induced asthma had indirect exposures to cleaning products and worked in administration, one in a school and one in a health care facility.

While this study adds to growing evidence, the authors identify the need for greater collection and study of workplace exposures to QACs noting, “…there is currently little information about exposure-response relationships because QACs have a low vapor pressure, and accurate sampling analytical methods have only recently been developed to detect very low levels of QACs in the air.”

Training for prevention

Both awareness and action are necessary to identify and reduce workplace exposures which can contribute to illnesses such as work-related asthma. Training is a great place to start.

If your workplace employs 20 or more workers or has a designated substance onsite a joint health and safety committee (JHSC) is required. Employers must also "carry out" Certification training for at least two members of the JHSC, one worker representative and one management representative, including approved JHSC Certification Part IJHSC Certification Part II and JHSC Certification Refresher. These programs are offered in safe, convenient WHSC virtual classrooms.

Employers in federally-regulated workplaces have similar training obligations, including those for members of work place and policy joint health and safety committees. Like their counterparts in provincially-regulated workplaces, these committee members play a significant role in developing programs to address workplace hazards.

Equally important your workplace needs to complete or review your WHMIS training. A surprising number have not. For instance, many have not fully transitioned from original WHMIS to Globally-Harmonized (GHS) WHMIS. We offer regularly scheduled GHS-WHMIS programs in our safe, convenient online virtual classrooms.

Don’t see what you need? Beyond scheduled classes, and where participant numbers warrant, we can work with you to coordinate almost any of our training courses including our Chemical Hazards training program for all your workers, workplace representatives and supervisors.

WHSC Related resources:
WHSC Hazard Resource Line: Occupational Asthma-Clearing the Air
WHSC Cleaning and Disinfecting: Confronting COVID-19
WHSC Evaluating Disinfectants for use against the COVID-29 virus
WHSC Webinar: Safer COVID-19 disinfectants
Contact a WHSC training services representative in your area.
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