Air pollution exposure in childhood is linked to mental health problems at 18

Key points

  • A recent study showed that young people who had been exposed to air pollution in childhood faced higher mental health challenges at the age of 18 compared with their peers who had less exposure.
  • Air pollution caused by smog, acid rain, motor vehicles and other causes can have a negative impact on the central nervous system, leading to these mental health problems.
  • Due to long-term exposure to air pollutants, people living near roads or other areas with the highest exposure to air pollutants are most vulnerable to negative effects.

New research published in JAMA Cyber ​​Open Highlight the actual impact of nitrogen oxides and particulate matter, two air pollutants that affect the central nervous system and cause physical and mental health problems.

These findings emphasize that children who are exposed to air pollution during development face a greater risk of mental health challenges than those who have less contact with their peers.

Understand the hazards of air pollution

Researchers tracked the entire childhood of 2,039 children born in the UK in 1994 and 1995, and then interviewed them when they were 18 years old to analyze the psychological symptoms associated with various risk factors.

The research team separated the risk factors of air pollutants and found that increased exposure to nitrogen oxides and particulate matter was associated with a greater risk of mental health problems.

Dr. Helen L. Fisher

Our findings indicate that adolescents exposed to higher levels of outdoor air pollution (especially nitrogen oxides) experience greater mental health problems during the transition to adulthood.

— Dr. Helen L. Fisher

Dr. Helen L. Fisher, a reader of the development of psychopathology at King’s College London, explained that nitrogen oxides (NOx) should not be confused with nitrous oxide or laughing gas, which is a different compound.

Dentists do not use nitric oxide. Instead, this compound has a strong, pungent odor, and is accompanied by the familiar brown mist, shrouded in large cities or industrial areas.

Dr. Fisher said that nitrogen oxides are a regulated compound produced by motor vehicles and industrial waste, and pointed out that high concentrations of compounds are often found near busy roads. She said these gaseous pollutants can lead to the formation of smog and acid rain.

In addition, the researchers measured the level of particulate matter or particle pollution, which are extremely small solid particles and liquid droplets suspended in the air. Dr. Fisher explained: “It mainly comes from motor vehicles, wood-burning heaters and industry. During forest fires or sandstorms, particulate pollution can reach extremely high concentrations.”

Exposure may cause mental illness

Researchers have found that the higher the rate of exposure to these air pollutants in childhood and adolescence, the more serious the overall mental health problems by the age of 18.

Dr. Fisher explained that these mental health problems include internally expressed conditions, such as depression and anxiety; externally expressed conditions, such as conduct disorder and drug abuse; and conditions related to thinking distortions, such as seeing or hearing non-existence Things.

These findings cannot be explained by other risk factors, including children’s previous mental health problems, biological factors and family history of mental illness, or risks related to poverty and neighborhood differences.

Dr. Helen L. Fisher

Air pollution may significantly increase the global burden of mental illness, and interventions to improve air quality may improve the mental health of the population.

— Dr. Helen L. Fisher

Dr. Fisher explained that air pollution has a negative impact on mental health and emphasized that exposure may be considered a risk factor for mental illness. Air pollution has been linked to Alzheimer’s disease, Parkinson’s disease, stroke and other central nervous system diseases.

Because of the correlation between early exposure and increased risk of mental health symptoms, other diagnoses (including mental illness) may be related to exposure.

How air pollution affects the brain

Experts know that these toxins affect the brain, which is clarified by their connection with central nervous system diseases. But Dr. Fisher explained that further research is needed to understand exactly how air pollution reaches and damage the central nervous system, and emphasized the need to continue to measure the link between exposure and negative outcomes.

She said that air pollution directly reaches the brain through the nasal nervous system and indirectly affects the brain through systemic inflammation. As we all know, air pollution enters the vascular system, thereby forming a pathway that may enter the brain through the blood-brain barrier. The blood-brain barrier is a semi-permeable boundary that controls the flow of nutrients and helps protect the brain from toxins.

Dr. Fisher explained that air pollution can interfere with the ideal function of the brain-ultimately leading to the destruction and death of neurons, which are cells that receive sensory input and send information from the brain to other parts of the body. Neurotransmitters that transmit signals between neurons play an important role in mental health. As we all know, imbalance and disruption can lead to certain mental health conditions.

These effects are chronic and cumulative, and may not cause actual effects for many years. Dr. Fisher pointed out that this is a particular concern for children whose brains may not be fully developed or may not function properly if affected, which may cause mental health problems.

In addition to affecting mental health by negatively affecting the central nervous system, air pollution is often accompanied by adjacent sources of stress. Dr. Fisher emphasized that nitrogen oxides mainly come from vehicle emissions and therefore cause traffic noise problems-which can disrupt sleep and cause other mental health problems.

Air pollution, global warming and injustice are intertwined

Dr. Fisher said that more research is needed to understand the impact of air pollution on specific populations. She explained that her findings are most relevant to countries with moderate air pollution and regulatory control, and explained that research should continue to determine the associations with countries with higher air pollution exposure rates (including China, Nepal, and India).

The World Health Organization currently estimates that 9 out of every 10 people in the world are exposed to high levels of outdoor air pollutants. Exposure comes from a combination of vehicles, power plants and waste treatment, as well as the combustion of fossil fuels in manufacturing and industrial processes.

The American Lung Association’s 2021 “State of the Air” report stated that “people of color are more than three times more likely to breathe the most polluted air than whites.” This emphasizes that the risk of exposure to marginalized people and the subsequent negative effects is much greater.

Elizabeth Brandt, field manager of Moms Clean Air Force, listed “heat islands”—urban areas with higher temperatures than surrounding communities—as a risk factor because air pollution levels increase as temperatures rise. People living and working in areas with a high concentration of buildings and little green space are 1 to 7 degrees higher than those in outlying areas. Blacks, people 65 years and older, and/or people with lower incomes have historically been the most negatively affected.

Elizabeth Brandt, MSW

Sometimes there is no way to stay away from the dirty air. The only way to protect your family is to make federal regulations to monitor things that cause air pollution.

— Elizabeth Brandt, MSW

Brandt emphasized that as the frequency and intensity of wildfires on and near tribal lands increase, climate change is affecting the air quality of indigenous peoples. Due to the reliance on old vehicles, and due to the lower access to electricity, and more reliance on generators, the community is also negatively affected by diesel fuel pollution. This highlights the link between systemic compression and increased risk of exposure to air pollutants.

Overall, air pollution levels have declined during the COVID-19 lockdown, which means that exposure may also be reduced. Forecasts indicate that behavioral changes due to the pandemic—that is, reductions in travel and daily commuting—have reduced nitrogen oxide pollutants in many regions, including major cities, by 11% to 49%. This highlights that, as a global community, it is possible to pursue measurable change.

How to safely enjoy the outdoors this summer

Although worries about air quality are serious, don’t let worries about air pollution keep you in it all season. The Centers for Disease Control and Prevention (CDC) explains that it is still safest to party outside with friends and family, especially when you are with someone who has not been vaccinated. This is also very beneficial to your mental health.

Compared with their peers, adolescents who can go outdoors during confinement have a higher rate of emotional health, and this number is even higher when spending time outdoors with their families. In addition, natural experience can reduce the symptoms of ADHD And increase mood and self-esteem.

Brandt emphasized that ozone pollution is a broad term, including nitrogen oxides and other gaseous pollutants, which are thermally reactive. This means that the situation will be worse when it is hottest outside. For many people, air pollution in autumn, winter, and spring is within acceptable limits, but it becomes a problem in summer.

Brandt says the best way to enjoy the outdoors in warm weather is to plan ahead. Schedule activities in the morning when the sun is not the hottest, and check local air quality reports before heading out on the adventure.

Understanding the risks will enable everyone to protect themselves and can inspire organized action against pollutants. Seek support through various national and local organizations that have collected resources and made a difference.

What this means to you

Despite the serious concerns about air pollution, you should still spend time outdoors on days and times when the risk of exposure is lowest. To limit the effects of air pollution, check your local quality report and plan a morning or evening outing.

If you want to learn more about the impact of air pollution on local communities and participate in efforts to take regulatory action against pollution, check out advocacy groups and connect with like-minded people who are already doing this work.

The information in this article is current as of the date listed, which means that you may receive updated information while reading this article. For the latest updates on COVID-19, please visit our Coronavirus News page.