Environmental Carcinogens and Cancer Inequality: How Air Pollution Challenges the Achievement of SDG 3

Background: Cancer has traditionally been understood as a disease driven primarily by genetic mutations; however, growing evidence indicates that environmental exposures play a significant role in shaping cancer risk and outcomes. Among these exposures, air pollution has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Beyond its biological effects, air pollution is unevenly distributed across populations, raising concerns related to health inequality and long-term public health sustainability.Methods: This narrative review synthesizes epidemiological and molecular studies examining the association between particulate matter (PM2.5) exposure and carcinogenesis. Key biological mechanisms discussed include oxidative stress, DNA damage, chronic inflammation, and epigenetic dysregulation.Results: The reviewed literature shows consistent associations between long-term PM2.5 exposure and increased lung cancer incidence and mortality, with more limited evidence for other cancer types. Unequal exposure to air pollution, combined with disparities in healthcare access, contributes to differences in cancer risk and survival across socioeconomic groups.Conclusion: By integrating biological evidence with environmental and equity perspectives, this paper highlights the importance of addressing air pollution as part of comprehensive cancer prevention strategies. Reducing environmental cancer risk factors is essential for promoting equitable and sustainable population health.