Could foods from the Mediterranean diet act as a DNA-protective tool against the mutagenic and genotoxic effects of urban fine air particulate matter (PM0.5)? An exploratory investigation on bacteria and human cell lines

Fine particulate matter (PM0.5) is an emerging public health concern due to its ability to penetrate deeply into tissues and induce oxidative stress–mediated damage, contributing to the development of chronic diseases. Despite increasing exposure in urban environments, its biological effects and potential mitigation strategies remain insufficiently explored. This study investigated whether selected foods typical of the Mediterranean diet (yoghurt, apples, lemons, peaches, kiwis, broccoli, onions, and tomatoes) can reduce PM0.5-induced DNA damage. The protective effects of these foods were evaluated using the Ames test on Salmonella typhimurium TA98 and the comet assay on human cell lines derived from lung (A549), liver (HepG2), and colorectal (HT-29) tissues. Exposure to PM0.5 organic extracts induced significant mutagenic and genotoxic effects. However, several foods demonstrated notable protective capacity. In bacterial assays, yoghurt, apple, onion, and tomato reduced mutagenicity by over 50%. In human cells, yoghurt and tomato (including tomato purée) showed the strongest protective effects, reducing DNA damage by up to 90% in A549 cells. Additional reductions were observed with peach, apple, and onion across different cell lines. These findings highlight the relevance of investigating PM0.5 toxicity given its implications for public health, and suggest that components of the Mediterranean diet, particularly fermented foods and vegetables, may play a role in mitigating DNA damage induced by fine particulate matter. Further studies are warranted to elucidate the underlying mechanisms and confirm the potential protective effects in vivo.