Investigation of the Cleanliness of Hospital Environmental Surfaces by Adenosine Triphosphate Bioluminescence Assay

Abstract

  This study evaluated the combined use of adenosine triphosphate (ATP) bioluminescence and microbiological assays for monitoring environmental surfaces in a teaching hospital to develop a method for rapid detection of microbial contamination that could constitute a health risk to patients. ATP bioluminescence assay and microbiological screening were performed of various surfaces of toilet facilities in outpatient wards. In each of the five sites screened, the ATP levels were significantly higher than on a cleaned, disinfected stainless steel surface, indicating that all screened surfaces were “high-touch” surfaces and the surfaces harbored significantly higher levels of certain organic matter. The microbiological assay confirmed that the microbiological contamination had spread throughout the screened sites. The ATP values of the samples positive for microbes occurred in a significantly higher range than those of the samples negative for microbes (p<0.01). However, no linear relationship was established between the ATP values and aerobic colony counts of the screened sites. These results clearly imply that the use of ATP bioluminescence to measure the microbial contamination of an environment yields qualitative rather than quantitative data. In conclusion, ATP monitoring is a rapid and convenient method to assess environmental contamination and persistence of microbes and to monitor the effectiveness of current cleaning practices.