Air pollution has become a serious public health problem globally. Recent studies support the harmful effect of air pollution on human health, in addition to scientific evidence that recognizes it as a human carcinogen. The buccal micronucleus cytome (BMC) assay is employed extensively to measure cytotoxic and genotoxic damage in a population exposed to environmental contamination. The objective of this study was to evaluate the cytotoxic and genotoxic effects in healthy young adults exposed to different levels of air pollution and to identify areas with air pollution rates above the regulatory limits. This study was performed through the BMC assay in oral mucosa samples from 80 healthy young adults from the Guadalajara metropolitan zone. Three highly contaminated areas were taken into account: Tlaquepaque, Miravalle, and Las Pintas. Las Aguilas, a less contaminated area, was used as a reference. The frequencies of nuclear abnormalities in the areas with the highest and lowest levels of air pollution were compared with the Mann–Whitney U test. In addition, an analysis of the concentration of environmental pollutants, particulate matter ≤ 10 μm (PM10), ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO), were carried out in the mentioned areas, in order to identify the events above the regulatory limits in a year period. The results showed that young adults exposed to a higher concentration of pollutants showed higher frequencies of nuclear abnormalities. The individuals from the areas of Tlaquepaque, Miravalle, and Las Pintas showed cytotoxic damage since statistically significant differences were found in the abnormalities of pyknotic nuclei (PNs), condensed chromatin (CC), karyorrhexis (KX), and karyolysis (KL). The individuals who showed the most cytotoxic damage were from the Las Pintas area with higher frequencies in nuclear abnormalities (PNs, CC, KX, and KL) (p < 0.0001). Genotoxic damage was found in individuals from two zones, Miravalle and Las Pintas, with statistically significant differences in the abnormality of nuclear buds (NBUDs) (p < 0.0001). Our results suggest that exposure to high levels of air pollution in healthy young adults has an effect on cellular and nuclear integrity and thus in human health, since areas with higher air pollution showed an increase in cytotoxicity, specifically in early and late markers of cell death (CC, KX, PN, and KL) and genotoxic damage (BUDs).

Major depressive disorder (MDD) is associated with complex neurobiological alterations in which oxidative stress may play a central role; however, direct evidence linking redox biomarkers to alterations in brain chemistry remains limited. This systematic review aimed to synthesize the available evidence on the relationships between oxidative stress and neuroimaging alterations in individuals with MDD. A search was conducted in PubMed, Scopus, and Web of Science (2016–2026) following the PRISMA guidelines, including human studies assessing oxidative biomarkers (central or peripheral) alongside neuroimaging or neurofunctional measures. Four studies met the inclusion criteria (case–control, cross-sectional, and interventional designs). These studies collectively indicate that antioxidant enzymes, glutathione, and malondialdehyde are associated with altered brain activity and connectivity, prefrontal neurochemical changes, and cognitive performance. Overall, the findings support the existence of associations between redox disruption and central nervous system (CNS) alterations in MDD. However, methodological heterogeneity and the limited number of studies highlight the need for further longitudinal and multimodal research to clarify the directionality and clinical relevance of these findings.