Inactivation of Escherichia coli O157:H7 and Salmonella during washing of contaminated gloves in levulinic acid and sodium dodecyl sulfate solutions. (August 2018) - Erickson, Marilyn C.
Abstract: Field workers often wear gloves harvesting ready-to-eat produce; however, fields are not sterile environments and gloves may become contaminated numerous times during a working shift. This study explored the potential for inactivation of Escherichia coli O157:H7 and Salmonella when contaminated gloves were washed in levulinic acid (LV) and sodium dodecyl sulfate (SDS) solutions. Washing nitrile gloves with increasing concentrations of LV above 1.0% led to a decreased prevalence of glove contamination by Salmonella ( P = 0.0000). A higher level of prevalence occurred for solid agar-cultured pathogens than liquid broth-cultured pathogens after nitrile gloves were washed in LV/SDS ( P = 0.0000). Pathogens residing on latex gloves were more likely to be completely inactivated by washing in 0.5% LV/0.1% SDS solutions than nitrile or Canners gloves that exhibited inconsistent responses dependent on the pathogen strain. However, drying after washing nitrile gloves in 0.5% LV/0.1% SDS led to additional pathogen inactivation ( P = 0.0394). Pathogen transfer from gloves to produce was implied as the pathogen prevalence on cantaloupe rind handled by LV/SDS-washed gloves was not statistically different from the prevalence on gloves ( P = 0.7141). Hence, the risk of produce contamination may still exist but would be reduced by washing gloves in LV/SDS. Highlights: Pathogen inactivation increased as levulinic acid concentration increased. One week old used levulinic acid solutions could inactivate pathogens. Drying gloves after washing in levulinic acid led to further pathogen inactivation. Culture conditions of the pathogen affected its resistance to levulinic acid. Transfer of pathogens to produce occurred from gloves treated with levulinic acid.