ÌìÃÀ´«Ã½

Newswise — In outpatient oncology clinics, the arms of treatment chairs are often contaminated with various chemotherapy medications. These chemicals are dangerous and can pose a risk to the health of patients and workers alike. Chair surfaces typically become contaminated when the needles used to deliver medication are removed.

In 2022, a study conducted across 124 Canadian hospitals revealed that contaminants were detected in 81% of the samples taken. In 74% of these cases, they found traces of cyclophosphamide, a chemical commonly used in chemotherapy. It contains molecules that cling to surfaces and therefore must be removed using special cleaning protocols.

This prompted Professor Jean-François Bussières from the Université de Montréal's Faculty of Pharmacy to test six decontamination methods as part of a broader monitoring program that he is involved in. The findings of the decontamination study, conducted with Cynthia Tanguay from UdeM's pharmacy research unit (URPP) and students Mathilde Dupré and Manon Marc, Bussières, were published in the Canadian Journal of Hospital Pharmacy.

Six decontamination simulations

The experiment was carried out on 59 samples of silicone fabric, similar to the material used for medical chairs. The researchers deliberately contaminated 56 of the samples with a predetermined amount of cyclophosphamide (10 micrograms) to assess the effectiveness of different cleaning solutions.

The decontamination products they tested included quaternary ammonium, 0.5% hydrogen peroxide, 0.005% detergent and 0.5% sodium hypochlorite. Each of the cleaning agents was applied using a microfiber cloth in a series of three successive cleanings. Afterward, any remaining chemical residues were measured using both liquid chromatography and spectrometry systems.

On average, the agents successfully removed 99.79% or more. In all cases, the efficacy was 99.3% after the first cleaning, 99.9% after the second cleaning and 99.95% after the third cleaning.

"Our simulations confirm the effectiveness of several different decontamination solutions, including sodium hypochlorite, which most people know as bleach," explained Professor Bussières. "Since the other products were also good, we recommend alternating between antiseptic and disinfectant solutions to prevent bioresistance in outpatient oncology clinics."

"Even though we clean the area between each patient, trace amounts of dangerous chemicals sometimes linger on the arms of treatment chairs. Our findings will help pharmacists, nurses and technicians reduce the risk of exposure for themselves and for patients," explained Mr. Bussières, who previously spent 26 years heading the Pharmacy Department at CHU Sainte-Justine.

A unique monitoring program

The decontamination study was part of a unique monitoring program that was set up in 2010 at CHU Sainte-Justine. The purpose of the program is to measure and reduce healthcare workers' exposure to hazardous drugs, like those used in chemotherapy.

"We publish our findings annually and work to reduce contamination risks through various interventions, guidelines, webinars and targeted strategies," said Bussières. "Our goal is to protect healthcare workers from exposure—and it's working!"

The program inspired the creation of a pan-Canadian initiative, which has now been implemented in more than 130 hospitals across the country.