Evaluation of decontamination strategies for cyclophosphamide

The main objective was to determine the efficacy of various types of cleaning equipment and products after deliberate contamination with cyclophosphamide. The secondary objective was to test various cleaning scenarios using these equipment and products.

The study had two phases: testing of cleaning equipment (wipe : woven microfibers - Hygen®, two layers of non-woven microfibres and an inner layer of highly absorbent viscose fibres - MicronSolo®, two layers of non-woven microfibres and an inner layer of highly absorbent viscose fibres - MicroMix®, simili-tissu (low filament production) - Tork® and, mop : woven microfibers - Hygen®, microfibre and viscose - MicroOne®) and products (disinfectant : quaternary ammonium - DR100®, chlorine 0.1% - Zochlor® - Brutab® - PCS® NPH, sodium hypochlorite 2%, cleaner : detergent - Nu- Action 3®, cleaner and disinfectant: sodium hypochlorite 0.6% + detergent - Aliflex® and water) in phase 1 and testing of various cleaning procedures in phase 2. Specific areas of a room with a laminar flow hood (class II/type B2) were contaminated with 10 mcg of cyclophosphamide. Different types of surfaces were cleaned with various scenarios and the remaining cyclophosphamide was measured by the Institut national de santé publique du Québec. All tests were performed in triplicate.

A total of 189 samples were obtained: 42 negative controls and positive controls, 54 during phase 1 and 93 during phase 2. All products were more than 96.5% effective. The 0.1% chlorines were the most effective products. Cleaning procedures with two or three products had average cleaning efficacies of 99.94-99.99%. Efficacy increased with the number of successive cleanings. When two products were used, the average cleaning efficacy varied between 99.78% and 99.98%, depending on the surface.

All cleaning products tested reduced cyclophosphamide contamination by more than 96.58%. Cleaning efficacy increased with successive cleaning. No scenario was effective in removing 100% of traces. Additional studies with larger samples should be conducted to confirm these results.