Pollution and Climate Changes as Environmental Determinants of Poor Mental Health

During the last decades, the uncontrolled urbanization process, together with the increase of anthropogenic activities, led to a significant increase in phenomena such as global warming and pollution. Human health is significantly threatened by these events and growing attention has been paid to their effects on mental health. Different mechanisms mediate the association between climate change and the possible development of psychiatric conditions, such as the occurrence of natural disasters that represent a major risk factor for post-traumatic and mood disorders. Moreover, such events may critically impact social determinants of mental health, contributing to inequality in food and water access, increasing social disparities, and disrupting social networks. Climate change also influences urbanization processes by causing ecomigration phenomena, and may as well determine higher pollution levels. As for the latter, air pollution has been confirmed as a crucial environmental determinant of mental health, leading to the development of psychiatric disorders and to the exacerbation of pre-existing conditions, also on the basis of neuroinflammatory pathway that may activate in response to pollutant exposure. Not only air, but also noise and light pollution cause a detrimental effect on mental health, acting through different mechanisms that involve the disruption of circadian rhythms as well as biological pathways related to inflammation and oxidative stress. In this chapter, an overview of the role of climate change and different sources of pollution as determinants of mental health is provided, and specific attention is also paid to the possible mechanisms through which these factors may act.