**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** CONTAMINATION OF READY-TO-EAT (RTE) FOODS WITH PATHOGENIC MICROORGANISMS CONTINUE TO POSE A SERIOUS RISK TO PUBLIC HEALTH. FOR YEARS, MULTIPLE CASES OF LARGE-SCALE OUTBREAKS AND RECALLS DUE TO ENVIRONMENTAL CONTAMINATION WITH SALMONELLA ENTERICA AND LISTERIA MONOCYTOGENES HAVE BEEN REPORTED. REINFORCEMENT OF CURRENT GOOD MANUFACTURING PRACTICES, IMPLEMENTATION OF NEW FSMA REGULATIONS AND DEPLOYMENT OF NEW INTERVENTION STRATEGIES HAVE YET TO RESULT IN A MARKED REDUCTION IN THE INCIDENCE OF RECALLS AND OUTBREAKS; IT IS THEN CRITICAL TO EXPLORE NOVEL TECHNOLOGICAL STRATEGIES. THE ENVIRONMENTAL CONTAMINATION WITH L. MONOCYTOGENES REPRESENTS A SERIOUS RISK FOR SEVERAL COMMODITIES SUCH AS DAIRY FOODS, FRESH PRODUCE AND FROZEN FOODS AS THIS BACTERIUM IS CAPABLE OF WIDESPREAD CONTAMINATION OF EQUIPMENT AND FACILITIES FOR PACKING AND PROCESSING. S. ENTERICA IS A FOODBORNE PATHOGEN OF CONCERN IN LOW MOISTURE FOODS, POULTRY, MEAT AND PRODUCE AND IS CAPABLE OF PERSISTING ON FOOD CONTACT SURFACES.THE USE OF A DYNAMIC AND HARMLESS LIGHT TECHNOLOGY DURING DOWN TIME AND CLOSE OF OPERATION COULD SERVE AS A USEFUL TOOL IN PREVENTING BIOFILM FORMATION AND PERSISTENCE. ANTIMICROBIAL BLUE LIGHT (ABL) TECHNOLOGY HAS BEEN EXPLORED FOR HOSPITAL DISINFECTION WITH VERY PROMISING RESULTS, BUT ITS APPLICATION TO CONTROL FOODBORNE PATHOGENS REMAINS RELATIVELY LIMITED.THE GOAL OF THIS PROJECT IS TO INVESTIGATE THE APPLICATION OF ABL FOR REDUCING THE SURFACE VIABILITY OF LISTERIA MONOCYTOGENES AND SALMONELLA ENTERICA BIOFILMS, AND OF FOODBORNE ASSOCIATED VIRUSES. SPECIFICALLY, THIS PROJECT WILL: 1) DETERMINE OPTIMAL ABL EMISSION DOSES TO INACTIVATE L. MONOCYTOGENES AND SALMONELLA BIOFILMS AS SINGLE SPECIES ON INERT SOLID SURFACES; 2) ASSESS THE IMPACT OF MIXED CULTURE BIOFILMS ON ABL EFFECTIVENESS TO KILL PATHOGENIC BACTEIRA; 3) DETERMINE OPTIMAL CONDITIONS TO INACTIVATE NOROVIRUS, HEPATITIS A VIRUS AND SARS-COV-2; AND 4) CHARACTERIZE THE POSSIBLE INTERACTION OF ABL WITH SANITIZERS TO INACTIVATEPATHOGEN BIOFILMS. THIS PROJECT WILL INCLUDE A SERIES OF LABORATORY EXPERIMENTS IN WHICH DIFFERENT SURFACES WILL BE INOCULATED WITH PATHOGENIC BACTERIA BIOFILMS AND VIRUSES, ABL-TREATED USING DIFFERENT CONDITIONS AND THE EFFECTIVENESS WILL BE MEASURED BY A COMBINATION OF VIABILITY DETERMINATION AND MICROSCOPY OBSERVATIONS.