Microbial contamination in grocery stores from Portugal and Spain: the neglected indoor environment to be tackled in the scope of the One Health approach

Microbial contamination in grocery shops (GS) should be evaluated since food commodities are commonly handled by workers and customers increasing the risk of food contamination and disease transmission. The aim of this study was to evaluate the microbial contamination in Portuguese and Spanish GS with a multi-approach protocol using passive (electrostatic dust cloths and surface swabs) sampling methods. The molecular detection of Aspergillus sections, mycotoxin analysis, screening of azole resistance as well as cytotoxicity measurement were conducted to better estimate the potential health risks of exposure and to identify possible relations between the risk factors studied. Fruits/vegetables sampling location was the one identified has being the most contaminated (bacteria and fungi) area in GS from both countries. Aspergillus section Fumigati and Fusarium species were observed in samples from Portuguese groceries with reduced susceptibilities to azoles commonly used in the clinical treatment of fungal infections. Fumonisin B2 was detected in Portuguese GS possible unveiling this emergent threat concerning occupational exposure and food safety. Overall, the results obtained raise concerns regarding human health and food safety and must be surveilled applying a One Health approach.