It’s no secret that air pollution is bad for human health. Asthma, cancer, and heart disease are better-known health risks of air pollution. 

However, growing evidence suggests toxic air may be a hidden factor in the rising rates of neurological disorders. (1, 2, 3)

Studies now link air pollution to several nervous system ailments. These include bipolar disorder, depression, epilepsy, Parkinson’s disease, personality disorders, and schizophrenia. (4)

Biochemical and genetic factors can also contribute to these illnesses. But the role of environmental pollution shouldn’t be overlooked. Air pollution, heavy metals, and neurological disorders are connected. After all, the air contains toxic chemicals and heavy metals.

Air Pollution Explained

Polluted air contains toxic chemicals and compounds that can harm health. Much of this pollution comes from car exhaust, factories, power plants, and wildfires. (4)

The toxins in the air can be liquids, gases, or solids. For example, carbon monoxide and sulfur dioxide are gases that pollute the air. Solid pollutants combine with liquid droplets to form particulate matter or tiny particles in the air. Hazy skies can sometimes come from particulate matter. (5)

Particulate matter is a mix of black carbon (such as from burning fuel), chemicals, dust, and toxic levels of heavy metals. Some heavy metals found in particulate matter are aluminum, cadmium, lead, and mercury. (6, 7, 8)

As people breathe, particulate matter enters the lungs. The smaller the particles, the more harmful they may be. Smaller particles can pass through the tissues more easily, including the brain. (6) 

The pollution of the air with particulate matter is very concerning. Most of the world’s population lives in areas where particulate matter exceeds World Health Organization guidelines. And growing evidence suggests poor air quality may harm the mental health of billions of people. (9)

How Pollution Could Affect the Brain

Air pollution is inflammatory and can damage cells and DNA, including brain tissues and nerves. This may play a role in brain dysfunction, including mental health disorders. (4)

Some research shows that the more particulate matter in a region’s air, the higher the risk of mental health disorders. However, the pollutants can interact with the brain if it’s damaged. (9)

Air pollution and the toxic state of heavy metals can weaken the blood-brain barrier. Animal research has shown that particulate matter can enter the brain. Scientists have confirmed the presence of heavy metals from air pollution in human brains after death. (4, 10, 11)

In addition, animal and lab studies suggest air pollution could damage the brain by a few different routes: (4, 12, 13)

  • Immune cells: White blood cells called macrophages could engulf pollutants and carry them to the brain. This would stimulate the brain cells to produce damaging inflammatory molecules. 
  • Nose: Toxins in the air may damage the barrier between the nasal passages and the brain. This gives pollutants easy access to the brain, including the limbic system, which is involved in emotions, learning, and memory. 
  • Systemic inflammation: As pollutants enter the lungs, this could trigger inflammation. This inflammation could spread to nerves distant from the lungs, which could trigger the brain cells to produce inflammatory molecules and damage DNA.  

Animal research suggests the hippocampus of the brain — which is part of the limbic system — may be especially vulnerable to inflammatory damage from particulate matter. (14)

Also, particulate matter may affect your risk of neurological problems by influencing gene expression. It could potentially “turn on” genes associated with mental health disorders. (15)

Pollution and Bipolar Disorder

Bipolar disorder — sometimes called manic-depressive disorder — affects about 3% of U.S. adults. It can cause extreme changes in mood and energy levels from feeling very “high” and energetic, and then suddenly very “low” and sad. (16)

Experts aren’t sure what causes bipolar disorder. Genetics likely play a role, as the disease tends to run in families. (17)

In addition, several studies have linked bipolar disorder to parasitic infection with Toxoplasma gondii. That’s a single-celled parasite people can get from undercooked, contaminated pork. People can also get it from contact with cat feces tainted with the parasite. (17, 18, 19)

Interestingly, studies have also linked allergies and asthma to an increased risk of bipolar disorder. In turn, asthma is commonly associated with air pollution. So, bipolar disorder could relate to air pollution. (2, 17)

Recently, a large study found that areas of the United States with the worst air quality had a 29% higher rate of bipolar disorder than regions with the cleanest air. (4)

Though more research is needed, such a link is plausible. Air pollution is associated with increased nerve inflammation and overstimulation of brain cells. And brain tissue from people with bipolar disorder has shown increased nerve inflammation and overstimulated nerves. (20)

Pollution and Depression

About 7% of American adults have significant depression. It may affect about twice as many women as men. (4)

This mood disorder manifests as sadness, emptiness, or a general lack of interest in life. Chronic illness, financial issues, and traumatic life events are among the potential triggers of depression. (21)

Scientists think there could be a connection between air pollution and depression. In one large study, teens and young adults exposed to the highest rates of air pollution as children had about 50% higher rates of depression. This was compared to those who grew up in the cleanest air. (4)

Another study compared daily air pollution levels with the number of depression-related visits to the emergency room. On days when particulate matter was elevated, 7% more women visited the ER. The same effect wasn’t observed for men. (22) 

A study of older adults found a 17% rise in depression symptoms when particulate air pollutants were elevated. Plus, higher levels of certain gaseous pollutants were linked to a 33–44% increase in depression symptoms. (23) 

Of course, these studies are observational and cannot prove air pollution is causing these effects. However, animal experiments support this link between depression and air pollution. 

When pregnant rodents were exposed to high levels of particulate matter, their offspring had altered brain development. The babies also had increased signs of depression compared to animals that weren’t exposed to the pollutants. (24, 25)

Pollution and Epilepsy

Epilepsy is a seizure disorder that affects about 1.2% of Americans. It results from overactivity of the brain, in which it sends too many nerve signals. Symptoms may range from small muscle twitches to full-body convulsions. (26, 27)

The cause of seizures isn’t always clear. Sometimes they’re triggered by injuries, strokes, or tumors. In addition, brain inflammation is a risk factor for seizures. (27)

Air pollution is one cause of the brain inflammation that leads to seizure activity. Studies in China — which has the highest air pollution in the world — have linked air pollution with epilepsy. Doctor visits and hospitalizations for epilepsy increase on days of higher air pollution in China. This pollution includes particulate matter, which contains toxic levels of heavy metals. (28, 29) 

Other research links heavy metals like lead, mercury, and nickel in the environment with higher epilepsy risk. Children may be especially vulnerable to the effects of heavy metals and air pollution. (30, 31) 

Pollution and Personality Disorders

Personality disorders involve extreme thought patterns. Some examples are antisocial behavior, narcissism, and obsessive-compulsive disorder. These disorders can stand in the way of living a normal life and having healthy relationships. (32) 

Unlike some mental health disorders, personality disorders are relatively common. It is estimated that 4–15% of people in the United States and Europe have personality disorders. (32) 

Both genetic and environmental factors contribute to the risk of personality disorders. This may include toxicity from air pollution. (33)

A recent, large study of teens and young adults is worrisome. It found that those exposed to the highest air pollution through age 10 had a 162% higher rate of personality disorders compared to those who grew up in the cleanest air. (4)

More research is still needed. However, this preliminary study suggests dirty air may contribute to unhealthy personality shifts.

Pollution and Parkinson’s Disease

Parkinson’s disease affects around 0.2% of the U.S. population, which is about 660,000 Americans. Men are almost twice as likely as women to develop the condition. (4, 34)

In this disease, nerve cells in a part of the brain that controls movement are damaged or die. That can result in poor balance, tremors, and trouble walking, among other symptoms. (34)

But before these severe impairments, more subtle alterations are going on behind the scenes. Figuring out the causes of early changes may point to preventable causes of the disease. (35)

A common change leading up to Parkinson’s is damage to the olfactory bulb, located above the nasal cavity. This structure helps process smell signals, and damage to it can weaken the sense of smell. (36)

Some evidence suggests injury to the olfactory bulb may be due to inhaling pollutants. This includes tiny airborne toxic heavy metals, such as founthose d in particulate matter. These metals may pass into the brain, leading to inflammation and nerve damage. (37, 38)

This brain inflammation may increase a protein called alpha-synuclein, which helps nerve cells receive messages. But in excess, these proteins can clump. This can disrupt the mitochondria in nerve cells — including in brain regions that control movement — and trigger nerve cells to die. (35, 39)

Consider a study done in Mexico City, one of the most highly polluted cities in the world. The research found healthy children already had alpha-synuclein buildup in their brains. This supports a link between air pollution and brain abnormalities that lead to Parkinson’s disease. (37, 40)

Pollution and Schizophrenia 

Schizophrenia is a relatively uncommon but serious mental health disorder. It can change how people behave, feel, and think. These people may have difficulty managing emotions, hallucinations, and trouble thinking clearly. (41, 42)

Several factors may contribute to the disorder. Irregular levels of chemical messengers in the brain are thought to play a role. Complications during birth, genetic factors, and virus exposure may increase the risk. (41, 42)

Scientists have also linked living in an urban setting with an increased risk of schizophrenia. This might be due to any number of factors related to city life, including air pollution. (43, 44)

Recently, a large study found that people exposed to the most air pollution in childhood had a 148% higher rate of schizophrenia than those growing up in the lowest pollution areas. (4)

Men may be at a slightly higher risk of schizophrenia than women. Some evidence suggests one reason for this is that a higher percentage of men work outdoors. That would expose them to more air pollution. (42, 45)

Researchers think that particulate matter is one factor in air pollution that may increase schizophrenia risk. Animal research supports this idea.   

When newborn mice were exposed to particulate matter, it caused structural brain changes commonly found in schizophrenia. These changes were found in male but not female mice. That’s consistent with human studies that show a little higher risk of schizophrenia in men. (42, 46, 47)

How to Protect the Brain 

No one can entirely avoid air pollution in today’s world. But that doesn’t mean they are helpless to protect themselves and their families from air pollution and heavy metal toxicity. There are practical ways to help protect the brain from pollution risks. 

Several diets, lifestyle choices, and supplements could help support and protect from the environmental toxicity that is everywhere.

Diet

It’s impossible to control what’s lurking in outdoor air, but you can certainly control their diet. Certain food choices may help counteract the effects of pollution. Eating healthy foods is also vital for good brain health and mental health in general. (48, 49)

Vitamins A (beta-carotene), C, and E are antioxidants that may help extinguish oxidative stress in the body, such as from air pollution. Here are some sources of each: (50, 51) 

  • Vitamin A — orange and yellow fruits and vegetables
  • Vitamin C — bell peppers, broccoli, kale, oranges, strawberries
  • Vitamin E — almonds, avocados, hazelnuts, and sunflower seeds

Plant-based foods also provide phytochemicals. These have antioxidant and anti-inflammatory properties that may help alleviate the toxic effects of air pollution. (52) 

In addition, a vitamin-like nutrient called choline supports brain health. Choline deficiency is linked to brain disorders and inflammation because people need it to make certain nerve messengers. This nutrient is found in eggs, meat, poultry, and quinoa. (50, 53)

Healthy fats are also important for brain function. An animal study suggests omega-3 fats may help prevent inflammation from particulate matter. You can get omega-3 fats from chia seeds, flaxseeds, and low-mercury fish like sardines and wild-caught salmon. (10, 50)

On the flip side, an excess of omega-6 fats can increase inflammation. Those are abundant in corn and soybean oils, which are prevalent in the Western diet. Read labels and avoid those oils as much as possible. (54, 55)

Lifestyle

To help reduce air pollution, people carpool or take public transportation, plus “go green” in other ways as well, like planting trees. Many people have encouraged their cities to develop more green spaces, such as parks and community gardens. 

One study found that children who grew up with the least amount of green space had a 55% higher chance of mental health disorders. Green spaces help soothe stress as well as decrease air pollution. Bushes, trees, and other foliage help cleanse the air of toxins. (56, 57)

Still, you should limit their time outside if poor air quality advisories have been issued. For example, in the United States, you can check the daily Air Quality Index. (58)

Lastly, you should not forget the pollutants in their home. Whole-house air filtration systems are sold as part of some heating, ventilation, and air conditioning (HVAC) units. They can also buy portable air purifiers to remove chemical pollutants. And, while they’re at it, they can choose a purifier that also removes mold toxins. (59)

Supplements

Dietary supplements that help with detox can be an important part of your arsenal against air pollution. The sooner they’re able to get rid of their toxic level of heavy metals and other toxins from air pollution, the less they can impact their brain.

Binders with Carbon Technology can form potent binders of heavy metals and other pollutants. These plant-based extracts of humic and fulvic acids have the ability to detoxify in the brain. Plus, they’re strong enough to carry heavy metals all the way out of the body, as explained in this short video. (60)

HM-ET Binder aids the body’s normal detox processes by binding and removing environmental toxins. It supports long-term maintenance by addressing common, daily exposures to toxins, plus provides nutritional factors to help maintain the structure and function of cells. 

But Carbon Technology does more than haul away toxins. It contains amino acids, antioxidants, and minerals. In short, it has everything the cells need to repair and rebuild after toxin exposure. (61)

CT-Minerals supplies naturally occurring plant-derived minerals and amino acids to support routine detoxification, as well as provide building blocks for cellular energy production.

Another helpful detox supplement is TUDCA because it may help increase the body’s natural excretion of bile. This increase can help purge heavy metals and other toxins the liver processes from blood. 

TUDCA may also protect the brain and nerve cells. One animal study suggests TUDCA reduces stress-induced epileptic seizures. This may be due to its ability to reduce damage from oxidative stress in nerve cells. (62, 63)

Advanced TUDCA is uniquely formulated, as it contains Carbon Technology, melatonin, NAC, and water-soluble bile TUDCA to enhance liver and digestive function to promote toxin elimination.

Lastly, heavy metals may create a low-oxygen environment called hypoxia. The brain needs a lot of oxygen to work well, so getting enough oxygen can help protect the brain from air pollution. (11, 64)

Defend the Brain

Like pesticides, polluted air is toxic because it contains harmful gases as well as particulate matter composed of toxic levels of heavy metals and other toxins.

Growing evidence suggests the toxins in air pollution increase the risk of brain disorders and poor mental health, including depression, Parkinson’s disease, and several others.

Thankfully, there are several ways you can protect yourself against these contaminants that could harm your brain.  

They can take Carbon Technology and supportive supplements like TUDCA to promote the removal of pollutants from their body. They can also follow a nutritious diet and limit time outdoors on days of poor air quality.

Because we cannot control the toxins invading the environment around us, it’s important to have foundational health be the priority in order to protect the brain from air pollution.