Executive Summary:

• The Department of Laboratory Animal Medicine at UCLA implemented a comprehensive environmental monitoring program (EMP) to validate sanitation processes in 10 buildings with 21 species, including 38,000 rodent cages.
• The EMP revealed challenges in the facility’s hygiene practices, particularly with respect to the amount of organic material remaining after cleaning the floors.
• The department aimed to consolidate to one cleaner/disinfectant for all surfaces in the animal rooms that had no odor, did not leave residue on surfaces, and had validated cleaning and biocidal efficacy.
• The cleaning effectiveness of two chemistries, hydrogen peroxide (H2O2) and an alkaline pH quaternary ammonium (Quat), was evaluated using cotton and microfiber mop heads.
• To establish consistency, a specific protocol was followed for mopping, and the behavior core tested the potential odor aversion for each chemistry versus tap water using a 3-chamber assay.
• ATP samples were collected before and after mopping to validate the biocidal efficacy of the chosen chemistry, and a standard was established using ATP testing.
• Four groups were set up and assessed, each consisting of one mop type and one disinfectant, and ATP samples were collected before and after mopping to determine the amount of organic material. Data were collected in four animal rooms weekly for three weeks, and a T-test was used to evaluate significance.
• The study found that both H2O2 and quat with microfiber decreased the soil load, with H2O2 being significant (p=0.0039) and quat trending towards significance (p=0.088).
• Mice displayed a significant aversion to H2O2 (p<0.0001), and rats had an aversion to H2O2, while both mice and rats displayed no preference or aversion to quat.
• Quat was chosen as the optimal product as it left no residue and did not foam up, and only 1.25 ounces of quat was needed compared to 2-8 ounces of H2O2.