Air pollution has become a major concern for our modern world. These pollutants are known to cause serious toxic impact on human health and the environment. According to the World Health Organization report, six major air pollutants include particle pollution, ground-level ozone, carbon monoxide, sulphur oxides, nitrogen oxides, and lead. Prolonged exposure to these suspended toxicants may have an impact on the human respiratory and cardiovascular system, neuropsychiatric complications, the eyes irritation, skin diseases, and long-term chronic diseases such as cancer. Several reports have shown the direct association between exposure to the poor air quality and increasing rate of morbidity and mortality. For years’ air pollutants have been associated to a range of health outcomes, most notably cardiovascular and respiratory diseases. However, the effects of air pollutants on mental health conditions have been less-well studied, and mostly confined to epidemiological studies. Observational evidence has revealed associations between increasing levels of several components of air pollution and a range of mental health outcomes. Air pollutants are also the cause of serious neurocognitive effects ranging from behavioural variations to neurodegenerative disorders that ultimately have devastating effects on mental health. Let us try to understand the air quality vs mental health debate in detail.
2. Air pollution has become a major concern for our modern world. These pollutants are known to cause serious toxic impact on
human health and the environment. According to the World Health Organization report, six major air pollutants include particle
pollution, ground-level ozone, carbon monoxide, sulphur oxides, nitrogen oxides, and lead. Prolonged exposure to these
suspended toxicants may have an impact on the human respiratory and cardiovascular system, neuropsychiatric complications,
the eyes irritation, skin diseases, and long-term chronic diseases such as cancer. Several reports have shown the direct
association between exposure to the poor air quality and increasing rate of morbidity and mortality. For years’ air pollutants
have been associated to a range of health outcomes, most notably cardiovascular and respiratory diseases. However, the
effects of air pollutants on mental health conditions have been less-well studied, and mostly confined to epidemiological
studies. Observational evidence has revealed associations between increasing levels of several components of air pollution and
a range of mental health outcomes. Air pollutants are also the cause of serious neurocognitive effects ranging from
behavioural variations to neurodegenerative disorders that ultimately have devastating effects on mental health. Let us try to
understand the air quality vs mental health debate in detail.
Introduction
3. Children's Mental Health
Children’s brains and behaviour are still in their
developing stages up to their late teens or early
adulthood, and poor air quality may have a
detrimental effect on their mental and emotional
growth. Recent findings suggest link between
PM2.5 and cases of mental health disturbances in
young children that are serious enough to send
them to the emergency room for psychiatric
evaluation.
4. A 2019 study published in Environmental Health Perspectives studied short-term exposure to PM2.5 in over 6,800 children up to
age 18 years old who were sent to an emergency department at the Cincinnati Children’s Hospital Medical Center in Cincinnati,
Ohio for symptoms considered psychiatric emergencies. These symptoms included suicidal thoughts, intense stress, sadness, and
anxiety triggered by a major life event. The study found that even a small, short-term increase in PM2.5 of 10 microns/ m3 may be
linked to a significant increase in the number of children brought to the hospital for severe psychiatric symptoms.
The researchers even suggested that PM2.5 exposure worsens existing inflammation in the brain caused by everyday aggravators
that result in mental health symptoms – specifically, in brain cells called microglia that react to life changes, social isolation, and
bullying. Meaning that children who are already stressed from the struggles of growing up could have a higher chance of
experiencing severe symptoms of mental health disorders when air pollution levels rise by an incremental amount.
Another study published in Psychiatry Research to give a clarity on air quality vs mental health, focused on 284 children who were
part of a long-term study of twins born to nearly 1,200 families in the United Kingdom between 1994 and 1995. Using the air
quality data from the addresses of these families along with data on mental health data medical and psychiatric evaluations of
the children themselves, the researchers concluded that even low PM2.5 and NO2 exposure in childhood may increase the risk of
major depressive disorders and conduct disorders by age 18 – the higher the pollutant concentration, the higher the possible risk
of depression.
5. After reading the above, we may think that just as symptoms of mental health
conditions get worse when airborne pollutants rise, they should also go away
once air pollution levels fall. But the impact of depression and conduct disorder
on the developing brain has lifelong consequences. In fact, childhood
symptoms of mental health conditions like depression and anxiety could lay the
groundwork in your brain’s wiring and chemistry for worsening mental health
symptoms into the teen years and beyond. This means that the longer
symptoms go unaddressed, the weaker the brain’s ability to process and cope
with these symptoms may become, leading to permanent or chronic anxiety
and depression.
6. Animal and human studies have established that exposure to particulate matter (PM) in the air
causes oxidative stress resulting in inflammation in the brain and body. Thus effecting different
structures of the brain, and interfering with normal production of cortisol the body’s major
stress hormone. The effects of air pollution on brain functioning may also be facilitated by
complex relationships between inflammation, oxidative stress, and physical inactivity, obesity,
and lack of sleep. Depending on the individual’s medical and psychiatric history, the duration of
exposure, and type of exposure, some or all of these mechanisms may play a role when an
individual is exposed to PM in the air, resulting in an increased risk of developing depressed
mood, anxiety and possibly other neuropsychiatric disorders.
7. In an analysis published in PLOS Biology of 151 million people in the United States and 1.4 million people in Denmark,
researchers found that environmental air quality is associated with increased risk of psychiatric disorders. The data was
indicative of long periods of increased air pollution, such as that found in major urban areas, may be linked to a nearly 17%
rise in cases of bipolar disorder. This also held true for major depressive disorder, with air pollution believed to have increased
depression diagnoses by up to 6%, and personality disorder, with increases in diagnoses by almost 20% in some cases.
Researchers pointed out that fine particulate matter like PM2.5 and ultrafine particles were the most potable suspects in the
relationship between air pollution and Post analysis of a series of earlier studies, the researchers laid out the following
conclusions about what may happen in your brain when you breathe in airborne pollutants that may affect your mental
health:
Pollutants
get into the lungs and cause inflammation in your windpipe and lungs. This can also inflame your nervous system.
Nervous
system inflammation is followed by increase in the number of inflammatory cytokines in your body and activates microglia
that react to stress. Such widespread inflammation may cause damage to your DNA.
8. also pollutants may get into your brain through thin nose membranes, where
neurons can transport PM2.5 through your olfactory (smell) system into brain tissue.
Pollutants that get into the brain damage the brain itself as well as brain structures in
Repeated exposures to PM2.5 can cause more and more damage to your limbic
system, potentially making mental health symptoms more severe.
the limbic system – which is directly responsible for your emotions.
Bottom line
While we laid air quality vs mental health to rest, we must not forget breathing in clean
air might be a significant step towards a better tomorrow, it has a many of the other
positive effects, including improved cognitive function and greater longevity. Remember
that mental health is holistic and there’s no all cure medicine for same.