Research shows that even low levels of air pollution can contribute to severe respiratory infections in adults. Study: Long-term exposure to air pollution and lower respiratory infections in a large population-based adult cohort in Catalonia . Image Credit: New Africa/Shutterstock.
com Lower respiratory infections (LRIs) are more common in children exposed to polluted air, but whether the same risk applies to adults has been unclear. A recent study published in Environment International explores this question, adding urgency to the effort to reduce air pollution. Introduction Air pollution is known to increase the risk of lung diseases like asthma, but its connection to LRIs in adults remains uncertain.
A 2022 meta-analysis found limited and weak evidence supporting a link between long-term air pollution exposure and adult LRIs. This association, however, is biologically plausible. Air pollution weakens alveolar macrophages' ability to clear infectious organisms, triggers inflammatory immune responses in the lungs, and upregulates cell receptors that allow pathogens to enter.
It also disrupts the gut microbiome , which plays a key role in protecting the body against harmful microbes. Men appear to be at higher risk for LRIs, potentially due to hormonal differences. Other risk factors include smoking, chronic liver and kidney disease, being underweight, and a history of prior hospital admissions.
While air pollution has declined in many regions over the past decade, even low le.