Prompt evaluation of cleanliness and disinfection efficacy is significant for on-site scenarios. Adenosine triphosphate (ATP) bioluminescence assay is effective for hygiene evaluation, while the ATP relative light unit (RLU) differs from various surfaces. This study compared the effectiveness of ATP bioluminescence assay and colony counting method in evaluating the cleanliness and disinfection efficiency on different surfaces, and to explore the feasibility of on-site ATP evaluation. Evaluation of disinfection efficiency was conducted in the laboratory floor by disinfecting 900 mg/L chlorine disinfectant for 30 min, and the ATP RLU and the total bacterial colonies were detected before and after disinfection. On-site sampling and detection of ATP and total bacterial colonies were performed on the surface and floor of the food processing workshop. Following the disinfection with chlorine disinfectant, the killing ratio of natural bacterial colonies and the elimination ratio of ATP RLU decreased by 90.52% and 86.87% respectively. Spearman rank-correlation analysis indicated that ATP RLU exhibited a positive correlation with colony forming unit (CFU). The ATP RLU of the tables and floors in the workshop were within the ranges of (14 - 849)/100 cm² and (131 - 8437)/100 cm² respectively, and the total bacterial colonies were within the ranges of (0 - 200) CFU/100 cm² and (30 - 800) CFU/100 cm² respectively. Pearson correlation analysis demonstrated that there was no linear correlation between Log RLU and Log CFU on the tables, whereas a linear positive correlation was detected for the floor samples. The decrease ratio of ATP RLU was consistent to the total colony count for disinfection, but the relationship was intricate in the cleanliness evaluation within the workshop. The two methods may be integrated comprehensively to evaluate the cleanliness and disinfection of surface.
Tao et al. (Thu,) studied this question.