Hidden Hazards at the Food, Utensil & Environment Interface: A One Health Assessment of Microbial, Chemical, and Emerging Contaminants and Foodborne Disease Risks

Abstract

Foodborne diseases are still a significant threat to human health, but the food utensil environment interface at which cross contamination of multiple hazard types occurs is largely under-researched. This research is the first One Health assessment to evaluate multiple types of microbial, chemical, and emerging contaminants at the same time in water samples, food processing units, street foods, and restaurants, as well as on food and utensils at households. A cross sectional design was used, with 216 sampling events, to combine culture based and molecular pathogen detection, heavy metal analysis by inductively coupled plasma mass spectrometry, microplastic identification using Fourier transform infrared and Raman spectroscopy and antimicrobial resistance gene screening using quantitative PCR, with a quantitative microbial and chemical cumulative risk assessment. Key findings showed that Salmonella and Campylobacter levels on utensils were 22 and 11 percent, respectively, and highest on street vendors; that the presence of indicator Escherichia coli and carriage of multiple resistance genes was highly associated with the presence of biofilms on cutting boards. A wide range of heavy metals, especially lead and nickel, and microplastic particles were found in all the samples, with a predominant presence of polyethylene and polypropylene fragments. Biofilm, microplastics and resistance genes co occurred, leading to synergistic effects which are reflected by an integrated risk estimate being 1.4 times higher than the sum of single hazard risks. The findings support the notion that the food utensil environment interface is a silent source of cumulative risk, which requires an integrated approach for monitoring multiple hazards and moving beyond a single- contaminant perspective to safeguard public health in a One Health context.