New British studies have underscored the serious health consequences of exposure to air pollution, emphasizing the urgent need to reduce airborne toxins. Air pollution, a global health crisis, has been linked to increased rates of cancer, heart and lung diseases, reproductive problems, and approximately 1.5 million deaths each year.
Contaminated air also worsens existing health conditions, with a 2020 inquest naming air pollution as the cause of death for a 9-year-old girl with asthma in Southeast London.
Link between air pollution and brain health
Emerging evidence suggests air pollution may also contribute to declining brain health. A recent study conducted by researchers at University College London (UCL) revealed a connection between exposure to two major pollutants and below-average cognitive function among older Britons. The pollutants studied were nitrogen dioxide (NO2), released by petrol-powered vehicles and industrial processes, and fine particulate matter (PM2.5), tiny airborne particles produced by burning fossil fuels.
Research findings on cognitive decline
The study, which analyzed data from the English Longitudinal Study of Ageing, found that individuals living in areas with higher ambient air pollution exhibited lower overall and executive brain function. Although the research established a strong association rather than direct causation, researchers are confident a deeper investigation would confirm the causal link. “We looked at ongoing exposure and pre-existing cognitive levels. We cannot be certain, but we’re confident there’s more than just an association,” said Paola Zaninotto, a medical and social statistician at UCL.
How air pollution affects the brain
According to researchers, cognitive decline may result from pollutants entering the bloodstream and damaging the temporal lobe — the brain area responsible for processing sensory information, language, memory, and emotions. Additional research from UCL specialists suggests that NO2 and PM2.5 negatively affect both the central nervous and circulatory systems.
Zaninotto warned, “The exposure is contributing to cognitive decline, which over time will lead to dementia. We need to start thinking seriously about reversing this trend.”
Challenges in reducing pollution exposure
Despite some improvements since 2010, even the lowest recorded exposure levels in the study were above World Health Organization (WHO) guidelines. WHO recommends air pollution levels not exceed 5 micrograms per cubic meter, yet the lowest exposure in the study was eight, with some areas reaching nearly three times the recommended limit as recently as 2017.
“There are improvements, but despite these, we are still a long way from adequately protecting brain health,” Zaninotto concluded.
