Poor Air Quality Could be Causing Poor Mental Health

Exposure to multiple air pollutants is associated with a significantly increased risk for depression and anxiety, new study observes.

Highlights:

The burden of diseases like depression and anxiety is surging, and identifying the modifiable environmental risk factors should be a priority
Growing epidemiologic evidence shows a relationship between air pollution and mental health disorders //
Air pollutants can cause the body to release harmful chemicals that can affect the brain and lead to anxiety and depression

A recent study shows that people who reside in a highly polluted area have a higher risk of depression and anxiety than those who live in a place with cleaner air.

The study found that people who were exposed to higher amounts of multiple air pollutants for a long time, including particle pollution, nitrogen dioxide, and nitrogen oxides had an increased risk of depression and anxiety ().

Air Pollution May Lead to Mental Health Conditions
People exposed to higher concentrations (above 10µg/m3) of fine particulate matter had a 21 percent increased risk of two or more co-occurring diseases.

‘A new study suggests that long-term exposure to even relatively low levels of polluted air raises the risk of depression and anxiety.’

Even Low Levels of Air Pollution can Affect Mental Health

The research assessed the records of 389,185 people from the UK Biobank, a large-scale biomedical database of half a million diverse volunteers. During the study period, 13,131 people were diagnosed with depression and 15,835 were diagnosed with anxiety.

Even when pollution levels were below UK air quality standards, people who lived in areas with higher pollution levels were more likely to experience depression and anxiety.

Particle pollution, also known as particulate matter, is the mix of solid and liquid droplets floating in the air. It can come in the form of dirt, dust, soot, or smoke. Coal and natural gas-fired power plants create it, so do cars, agriculture, unpaved roads, construction sites, and wildfires.

Nitrogen dioxide pollution is most commonly associated with traffic-related combustion byproducts. Nitrogen oxides are also released from the burning of oil, coal, and natural gas.

Air Pollution May Up Mental Health Problems in Kids
Prolonged exposure to outdoor air pollution can cause mental health problems in kids and also worsen the symptoms of psychiatric disorders, like depression, anxiety, and suicidality.

PM2.5 Could be the Culprit

The smallest particulate matter included in the new study, PM2.5, is just 1/20th the width of a human hair. This makes it easy to travel past the body’s usual defenses.

It may remain in the lungs or enter the circulation instead of being expelled, when you breathe. The tiny particles cause irritation and inflammation and could lead to respiratory problems. Long-term exposure can cause cancer, stroke, or heart attack. Apart from that, it can also aggravate asthma, and it has long been associated with a higher risk of depression and anxiety.

The risk of anxiety linked to PM2.5 pollution was stronger in men than in women.

While the study is unable to exactly pin point the reason for the overall link, other studies have found that exposure to air pollution may affect the central nervous system, causing inflammation and damaging the body’s cells ().

Depression - Types, Causes, Symptoms, Diagnosis, Treatment
Depression is one of the most common mental disorders affecting approximately 340 million people in the world. No one is immune from depression - it occurs in people of all social classes, all countries and all cultural settings.

How Pollutants may be Affecting the Brain

Some studies show that air pollutants can also cause the body to release harmful substances that can hurt the blood-brain barrier. This is the network of blood vessels and tissues made up of closely spaced cells that protect the brain, and may lead to anxiety and depression ().

Several studies indicated that short-term exposure to air pollution was associated with increased risk of hospitalization or outpatient visits for depression as well as anxiety.

But more research will be needed to fully understand this connection, because the neural basis for both anxiety and depression is not completely understood.

The limitations of the new research include a lack of information about other common air pollutants like ozone, carbon monoxide, or sulfur dioxide. Not all air pollutants are created equal. Some are more toxic than others. And for certain diseases, there’s still a lot of work to be done.

The study authors hope the research will encourage public policymakers to do what they can to reduce exposure to pollution.

Researchers state that, considering that many countries’ air quality standards are still well above the latest World Health Organization global air quality guidelines 2021, stricter standards or regulations for air pollution control should be implemented in future policymaking.

References:

Long-term Exposure to Multiple Ambient Air Pollutants and Association With Incident Depression and Anxiety - (https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2801116)
Association Between Ambient Air Pollution and Daily Hospital Admissions for Depression in 75 Chinese Cities - (https://pubmed.ncbi.nlm.nih.gov/32312109/)
Association between short-term ambient air pollution and outpatient visits of anxiety: A hospital-based study in northwestern China - (https://pubmed.ncbi.nlm.nih.gov/33798515/)

Source-Medindia

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