Safe disposal of E. coli DH5α strain from liquid broth and solid substrate

The Journal of Environmental studies (JES) 
Vol.23: 1-12 (23), 12 pages
Author:.Gustavo Vinicius M. P. et al '
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Healthcare waste contains potentially infectious agents that represent risks for human health and the environment. Many techniques can be used to decontaminate these infectious wastes and make the management process safer and less costly. In the present study, various chemical disinfectants were used to decontaminate concentrated E. coli DH5α strain bacterial broth used in laboratories, as well as gauze contaminated with these bacteria. Dose-response statistical regressions were performed after multiple comparisons using the Kruskal-Wallis test with Nemenyi post-hoc. Fifty percent lethal concentration (LC50) for E. coli DH5α was 0.0586% for sodium hypochlorite (NaOCl), 0.0243 % for hydrogen peroxide (H2O2), 0.0161 % for formaldehyde, 12.20 % for ethanol, and 0.00401% for quaternary ammonium (BADAC-DDAC). When used to treat solid waste, all the chemicals used were able to completely disinfect the gauze when the concentration of 5×LC50 was used. This research highlights the adoption of biocides as efficient, low-cost alternative healthcare waste treatment options.


infectious waste, healthcare waste, chemical decontamination, waste treatment.