Air Pollution: Possible Interaction between the Immune and Nervous System?

Abstract

Exposure to environmental pollutants is a serious and common public health concern associated with growing morbidity and mortality worldwide, as well as economic burden. In recent years, the toxic effects associated with air pollution have been intensively studied, with a particular focus on the lung and cardiovascular system, mainly associated with particulate matter exposure. However, epidemiological and mechanistic studies suggest that air pollution can also influence skin integrity and may have a significant adverse impact on the immune and nervous system. Air pollution exposure already starts in utero before birth, potentially causing delayed chronic diseases arising later in life. There are, indeed, time windows during the life of individuals who are more susceptible to air pollution exposure, which may result in more severe outcomes. In this review paper, we provide an overview of findings that have established the effects of air pollutants on the immune and nervous system, and speculate on the possible interaction between them, based on mechanistic data.

Keywords: air pollution; central nervous system; hygiene hypothesis; immune system; microbiota; skin.

Figure 1

Effects of indoor and outdoor air pollutants on immune and nervous system. Susceptibility during critical windows and involvement of oxidative stress and inflammatory pathways are reported.

Figure 2

Main effects of air pollutants on immune and nervous system. Summary of the results reported in Table 2 and Table 3.