Humanity’s rapid industrialization and rampant use of combustible fuels has led to widely documented changes in the atmosphere of the planet in what can only be described as a climate catastrophe. The airways which all aerobic life on Earth depend upon have become clogged with the gaseous byproducts of human industry. These contaminant gasses have been implicated in the causation and exacerbation of a plethora of adverse effects on human health such as respiratory irritation, chronic heart and respiratory diseases, respiratory infections in children, chronic bronchitis in adults, asthma attacks, lung cancer, and the aggravation of pre-existing heart and lung diseases (Kampa & Castanas, 2008). Just as concerning are the potential long-term impairments of mental health, such as increasing risks of depression, anxiety, and various forms of dementia, including Alzheimer’s disease (Borroni et al, 2022; Manczak et al., 2022; Power et al., 2015; Sahu et al., 2021; Shi et al., 2021).
Due to the widespread nature of this global catastrophe, these side effects of air pollution can cause significant changes in the general health of any given population, especially those afflicted by a lower socio-economic status and racial disparities, which are more frequently exposed to contaminated air (Hajat et al., 2015; Tessum et al., 2019). Entire cultures and communities are potentially facing significant changes in behavior, as increases in anxiety and depression across an extensive population will undoubtedly lead to changes in the way people relate and feel towards one another.
Air pollution as a concept is an umbrella term for the combination of contaminants that tend to be most present or concentrated in urban airways. Ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide are some of the general constituents of air pollution that have shown significant correlation with issues regarding mental health, such as dementia and depression (Borroni et al., 2022; Shi et al., 2021). Fine particulate matter of less than 2.5 micrometers in diameter is also a major constituent of global air pollution that has been linked with adverse health effects. The World Health Organization presents air pollution as the greatest environmental threat to human health, with data from the year 2012 showing that one out of every nine deaths can be attributed to a condition related to air pollution (World Health Organization, 2016).
Of particular concern is the unequal distribution of air pollution exposure in places such as North America, New Zealand, Africa, and Asia (data for Europe is mixed), where an individual from a lower socioeconomic status is significantly more likely to face higher levels of pollution which could adversely affect their wellbeing (Hajat et al., 2015). This inequality is also reflected racially, especially in the United States; research shows that Black and Hispanic communities in the US face much higher levels of fine particulate matter pollution than non-Hispanic White communities.
The contamination of the airways has also been observed to negatively impact neurological health during prenatal development. The incidence of certain autism spectrum disorders have been correlated with exposure to high levels of nitrogen oxide during pregnancy (Pagalan et al., 2019). A particularly comprehensive study has found correlations between various different forms of brain structure alterations in children and adolescents and exposure to air pollution during pregnancy and early childhood. Living in areas with excessive air pollution has also been found to negatively impact social and emotional health.
Seeing as how air pollution is potentially responsible for widespread feelings of depression and anxiety amongst a large population, there is a possibility that the social dynamics of large swathes of people could change as a result. Feelings of depression and stress are consistently correlated with feelings of loneliness (Tzouvara & Kupdere, 2022). According to research performed by renowned neuroscientist John T. Cacioppo, individuals with feelings of loneliness demonstrate different behavior towards others. Although an individual who feels lonely will attempt to connect with others, they will also have more defensive or self-protective mindsets, which can be perceived negatively by others.
According to the theory of emotional contagion, as people have conversations and interact with one another they synchronize their behaviors in what could be considered a form of social mimicry. In this manner, an individual exposed to what is perceived as a negative attitude or behavior can have their own emotions change as they reflect what they are experiencing. This is what is known as “catching” someone else’s emotional state, which implies that positive or negative emotions could spread from individual to individual (Hatfield et al., 1993). Consequently, feelings of loneliness and depression could create a large social environment made up of adverse emotional states. It is for this reason that the threat of air pollution is much larger than simply causing adverse health effects; it could negatively alter the way in which the members of entire communities interact with each other.
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