29 October, 2018. The most obvious brain drainers have already been discovered, such as mercury, lead, or organophosphate pesticides, but the list is much longer when it comes to suspected neurotoxicants. Many of them are mediated through food and water consumption. But, what about the air we breathe? This field is somewhat more complex, as the air pollution and its composition varies from place to place, with the season, time of the day, and other factors. Air pollution includes carbon monoxide. a known human neurotoxicant, certain metals, nitrogen oxides, and less certain neurotoxicants such as tar compounds and particles of mixed composition. However, the evidence is building – the air that we breathe may impact on the next generation’s brain development. Today, the EU Environment Agency warns that air pollution is too high and “an invisible killer”. It is more than that.
One of the strongest pieces of evidence is a large study conducted in Barcelona by ISGlobal researchers. They assessed whether exposure to different degrees of traffic air pollution of primary school-aged school children was associated with cognitive development during a 12-month period, using repeated scores of standardized working memory and attentiveness tests over time. Children exposed to higher levels of traffic-related air pollutants at school showed reduced cognitive improvement, thus emphasizing the continued vulnerability of the brain during postnatal development. Now, a study in adults suggests that breathing unsafe levels of air pollution may be linked to deficient or declining cognitive performance, thereby implicating also the mature nervous system. The study looked at the relationship between the measurement levels of sulfur dioxide, nitrogen dioxide and particulates smaller than 10 micrometers in diameter where a participant lived and the cognitive performance, in this case, the math and verbal skills. The study included about 20,000 people over a four-year period. The findings highlight the added urgency of dealing with this particular ubiquitous, global exposure source and the impact it has on the developing, as well as mature, brain. Although the latter study was carried out in China, air pollution is a global problem.
The EU Commission knows, and Environment Commissioner Karmenu Vella in January asked member states to submit their plans to bring down air pollution levels to comply with EU law: “I urge all member states to address this life-threatening problem with urgency.” Several months later, eleven EU member states asked the Commission for an extension: Austria, Belgium, Denmark, Finland, France, Germany, Hungary, Ireland, Luxembourg, Spain and the United Kingdom. Most commonly, the limit for nitrogen oxides (NOx) has been exceeded. The EU limits are thought to be health-based, but they do not take into account potential adverse effects on brain functions and development. Can we please clear the air and eliminate brain drainers from the atmosphere?