STUDY ON GERMICIDAL EFFIACY AND TOXICITY OF SOLID CHLORINE DIOXIDE DISINFECTANT

In order to study the germicidal efficacy and toxicity of solid chlorine dioxide disinfectant,carrier immersion quantitative germicidal test and animal test method were used to carry out laboratory and field experimental observation.Results: The average killing logarithm values of Esherichia coli,Staphylococcus aureus,Pseudomonas aeruginosa and Candida albicans on carriers exposed to the water solution containing chlorine dioxide disinfectant 103.9 mg/L for 2.5 min were 3.00.The solution containing chlorine dioxide 2 mg/L with a 10 min contact time reduced E.coli in artificially contaminated water sample to 0 cfu/100 ml.The temperature,pH and organic substance did not obviously influence the efficacy of the disinfectant in disinfection of water.The killing logarithm value of E.coli on tableware immersed in the disinfectant solution containing chlorine dioxide 103.9 mg/L for 10 min was 3.00 and the killing logarithm of the natural bacteria on surface wiped with the disinfectant for 5 min was 1.00.Adding 2 mg/L chlorine dioxide to the natural reservoir water and allowing it to dwell for 10 min could reduce E.coli in the natural reservoir water to 0 cfu/100 ml.The mouse oral toxicity LD_(50) of chlorine dioxide was 5000 mg/kg(bw),belonging to essentially non-toxic class.It had no cumulative toxicity and did not induce micronucleus formation.Conclusion: The solid chlorine dioxide disinfectant has relatively good efficacy in killing vegetative forms of bacteria and fungi and belongs to non-toxic class in animal test.