The Link Between Autism and Environmental Toxicity: Exploring the Latest Research

by | Apr 17, 2023 | Autism, Blog, Detoxification

Did you know that air pollution and environmental toxins may increase the risk of autism? It’s true. Toxin exposure is not great news for anyone, but it’s particularly risky if we are talking about autism. Air pollution and environmental toxin exposure during pregnancy, infancy, or childhood may increase the risk and worsen the symptoms of autism. 

In this article, I want to discuss the latest research on the link between autism, air pollution, and other environmental toxins. I will offer some tips on how to reduce your environmental toxin exposure and how to protect your and your children’s health.

What Is Autism?

Autism spectrum disorder (ASD) or autism refers to a range of conditions that can cause significant social, behavioral, and communication challenges. According to the Government of Canada, about 1 in 66 children are affected by autism in Canada (1). According to the Centers for Disease Control and Prevention (CDC), 1 in 44 children is diagnosed with autism in the US (2). 

In reality, the numbers may be higher than these official statistics. Unfortunately, many families don’t have the financial access to receive a diagnosis. Despite the increase in online diagnosis and therapy, many families still don’t have access to professional diagnostics and support. Many are on a long waitlist due to the lack of providers or insurance regulations. Seeking an autism diagnosis is also emotionally challenging and may delay action. Moreover, adult diagnosis of autism is increasingly prevalent as well. About 2% of adults are diagnosed with autism. This suggests that many autism diagnoses have been and are missed during childhood (3, 4).

Autism has various subtypes that may be influenced by both genetic and environmental factors. In this article, I will discuss environmental factors, more specifically, environmental toxins behind autism. 

The symptoms and experience of autism may greatly differ from person to person. For example, learning, thinking, and problem-solving abilities may range anywhere from highly gifted to severely challenged. Social interactions may be incredibly challenging for some but less so for others. While many people with autism can lead a healthy and productive life, others may need help with their daily lives for their entire life. 

Autism may co-occur with attention deficit/hyperactivity disorder (ADHD) (5, 6). Children and adults with autism may experience other mental health issues as well, including obsessive-compulsive disorder (OCD), anxiety, depression, and eating disorders, especially Avoidant Restrictive FOOD Intake Disorder (ARFID) (7, 8, 9, 10, 11, 12).

Research to understand autism and treatment options is still ongoing. There are many factors that may influence the development and symptoms of autism, including genetics, family history, other medical issues, other mental health challenges, and environmental factors. Treatment of autism often involves a group of healthcare providers from various areas of expertise.

Exposure to environmental toxins during pregnancy, early childhood years, and throughout life may increase the risk and symptoms of autism. In my practice, I’ve found that reducing environmental toxin load and detoxifying from environmental toxins can be very helpful in autism for improving health, function, and well-being.

New Research on Autism and Air Pollution

Did you know that air pollution may play a role in autism? Two new research studies have found that exposure to air pollution during pregnancy and childhood may increase the risk and symptoms of autism.

A 2022 study published in BMJ Open has found that school-aged children (ages 5 – 14 years) with autism had a greater risk of hospitalization from short-term air pollution exposure (13). Researchers found a risk for hospitalization within 1 day of exposure to fine particulate matter (PM2.5), within 5 days of exposure to nitrogen dioxide (NO2), and within 4 days of exposure to ozone (O3). They found that boys were at a higher risk of hospitalization than girls. Out of the mean count of 8.5 daily hospital admissions, 7.0 were boys and 1.6 were girls.

Air pollution may impact the central nervous system. It may activate the microglia, which are resident immune cells in the brain that constantly check for and respond to pathogens and damage. Air pollution may disrupt the blood-brain barrier and increase oxidative stress, chronic inflammation, neuroinflammation, neurodegeneration, cerebrovascular injuries, and other brain health issues (14, 15, 16, 17, 18, 19). 

Even short-term exposure may increase the production of proinflammatory cytokine production. It may impair communication skills or affect the behavior of children (20, 21, 22). Since behavior, communication, and other issues can already be a challenge for many children with autism, it’s not surprising that exposure to air pollution may further aggravate the issue.

Air pollution is, of course, not only a problem for school-aged children. It can become a serious risk for younger children, as well as during pregnancy. A 2021 study published in Epidemiology has looked at the effects of air pollutants “3 months before pregnancy, each trimester of the pregnancy, the entire pregnancy, and the first year of life” (23). 

Researchers found that the risk of autism may depend on the window of exposure to air pollution. They found that the late prenatal and the early postnatal period may hold the highest risk for autism. This may not be surprising since this is the period when brain structures are already formed and neuronal maturity is rapidly increasing. Neuroinflammation and oxidative stress from environmental pollution or other toxins may be particularly harmful during this time.

A 2023 study from Sweden published in Scientific Reports has also found air pollution during pregnancy may hold an increased risk for autism (24). They found that air pollution from tailpipe exhaust, wood burning, and vehicle wear-and-tear during pregnancy may increase the risk of childhood autism.

Autism and Environmental Toxins

Air pollution is not the only source of harmful environmental toxins that may increase the risk and worsen the symptoms of autism.

A 2012 article published in Environmental Health Perspective by The National Academy of Sciences has reported that about 3% of all neurobehavioral disorders, including autism and ADHD, may be linked to environmental toxin exposure (25). They found that about 25% are linked to the interaction between genetics and environmental factors.

Understanding the connection between toxins and chemicals and autism is still ongoing in research. Unfortunately, many widely used chemicals haven’t yet undergone assessment regarding potential toxicity and risk for autism and other neurodevelopmental issues. The Children’s Environmental Health Center (CEHC) has created a list of chemicals that may be key suspects for the increased risk of autism and learning disabilities (25, 26). 

These environmental toxins include increase the risk or worsen the symptoms of autism (25, 26):

  • Lead
  • Methylmercury
  • PCBs
  • Organophosphate pesticides
  • Organochlorine pesticides
  • Endocrine disruptors
  • Automotive exhaust
  • Polycyclic aromatic hydrocarbons
  • Brominated flame retardants
  • Perfluorinated compounds

A 2017 review published in Molecular Autism has found that 40 – 50% of autism cases are linked to environmental factors, including some evidence that heavy metal toxicity may contribute to the risk factors (27). A 2021 review published in Pediatric Perspectives has found that air pollution, neurotoxic and endocrine-disrupting pesticides, including organochlorines, organophosphates, pyrethroids, and other toxic chemicals may play a role in the development of autism (28). 

A 2021 review published in Molecular Psychiatry has also found that environmental exposure to toxins and heavy metals during pregnancy and after birth may increase the risk of autism (29). Just like air pollution, other toxins, chemical, and heavy metal exposure may increase the risk of oxidative stress, oxidative DNA damage, chronic inflammation, mitochondrial dysfunction, neuroinflammation, and immune dysregulation, which may contribute to the increased risk and worsening symptoms of autism (29, 30, 31, 32, 33, 34, 35).

Recommendations for Toxin Load with Autism

Reducing toxin overload and detoxifying your body from toxins is important for everyone. When it comes to autism, it is important to take steps to reduce toxicity not only in children but also during pregnancy, and, ideally, while trying to conceive, as well as for teens and adults with autism. 

While avoiding environmental toxins completely is near impossible, there is a lot you can do to decrease your toxin load and support your and your child’s body. Here is what I recommend:

Move to Less Polluted Areas

Air pollution is a major risk factor when it comes to autism. Those living in large cities and highly polluted areas are at higher risk. Moving to less polluted areas seems like an obvious solution. This is also the least convenient option. Not everyone is able to move elsewhere. Jobs, family, friends, good school districts, and other reasons may keep you where you are. If moving is an option for you, however, considering less polluted areas, such as smaller towns or the countryside, may be something to consider.

Spend Lots of Time in Nature

Spending time in nature is a great way to get some fresh air. No matter where you live, try to spend as much time in nature as you can. Strolling down in a city park or a bike ride on the trails can be a great option. Even better, drive out to a national, state, provincial, or county park for a hike or a picnic. Go volunteer at a local Community Supported Agriculture (CSA) farm or try (organic) fruit picking with the family. Nature time is not only great for getting fresh air, it’s also relaxing and great for mental health. Many children with autism tend to feel overstimulated in loud and busy environments. Being in nature may just be ideal for them. Spending time outdoors may increase sunlight exposure and vitamin D levels.

Use an Indoor Air Filtration System

You may not be able to control your outdoor air, but you can certainly indoor your indoor one. Using a high-quality indoor air filtration system can help to remove toxins, mold, allergens, viruses, and other pathogens from your indoor air. Having some nice indoor plants can also improve fresh oxygen levels in your home. Water damaged homes leading to potential mold toxin exposure definitely needs to be addressed when this is an issue.

Drink Purified Water

Unfortunately, city tap water can be filled with toxins. I recommend using a water purification system. If you are out and about, either use a water bottle with a water purifier or buy spring water. Adding lemon, lime, cucumber slices, berries, mint, or basil to your water adds extra flavor and nutrients. 

Eat Organic, Non-GMO, and Non-Processed Whole Foods

Follow an anti-inflammatory, nutrient-dense diet high in organic greens, vegetables, herbs, spices, sprouts, fermented food, fruits, nuts, seeds, legumes, and organic animal protein. To reduce your risk of exposure to pesticides and herbicides, I recommend buying organic, non-GMO produce. For animal products, I recommend buying organic, grass-fed meat, pasture-raised poultry and eggs, wild-caught fish, or wild game to reduce exposure to hormones and antibiotics. 

Unfortunately, recent research is showing that a large percentage of baby foods are contaminated with heavy metals. I know, this is very disturbing. Rice and rice-based products, including pablum or cereals, are a real culprit when it comes to arsenic exposure, for example.  Lead shows up in baby food as well.  To learn more about this very important topic, I like this resource

Avoid or reduce the consumption of overly processed foods as they usually include additives, unnatural ingredients, and other inflammatory ingredients. Avoid food sensitivities. For babies, opt for breastfeeding if possible. Once they start solids, choose organic and ideally homemade foods instead of conventional baby products. You may also read about the top potential nutrient deficiencies in autism and how to avoid or correct them here.

Upgrade Your Kitchen

Your cookware matters too. Avoid non-stick, aluminum, and copper cookware. Choose stainless steel, cast iron, glass, and ceramic cookware, depending on your needs. Reduce the use of plastic. For storage, use glass containers, silicone zip lock bags, cloth bags, paper bags, and beeswax wraps, depending on the food. Avoid plastic, especially BPA. Instead of plastic water bottles, use mason jars, glass bottles, or stainless steel. Instead of plastic bags, choose organic cotton cloth bags. Instead of plastic cups, plates, or utensils, choose glass, bamboo, or ceramic options. If you need something you would throw out, choose biodegradable options.

Choose Biological Dental Care

Avoid mercury-filled amalgam silver fillings. If you have any, consider getting them removed by a biological dentist. Avoid conventional dental hygiene options and fluoride-filled toothpaste. Choose natural and organic options. Working with a biological dentist can recommend holistic dental care options.

Upgrade Your Cleaning and Personal Care Products

Avoid using conventional cleaning, personal hygiene, body, and beauty products. Choose organic, natural, and homemade options instead. If you have a baby or a young child, choosing cloth diapers may be a better option. Pay extra attention to the products you are using, including soap, shampoo, baby creams, and wipes. Read the ingredients and choose chemical-free organic, natural options if you can’t make your own as much as possible. Good old-fashioned vinegar, water, and baking soda are worthy cleaning options.

Avoid Overusing Medications

The overuse of antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), over-the-counter (OCT) medications, and prescriptions can increase the risk of gut health imbalances, antibiotic resistance, immune health issues, and all kinds of other problems. Only use medications when necessary and as prescribed. Talk to your doctor to see what you or your child needs to take instead. Choose natural options whenever possible.

Support Detoxification Pathways

Support digestion through a gut-friendly, anti-inflammatory diet as outlined earlier. Take a daily high-quality probiotic supplement. Try using activated charcoal or other toxin binders to help absorb and eliminate toxins. Support detoxification through sweating by moving your body and using an infrared sauna. Support lymphatic flow through rebounding, dry brushing, and moving your body. You may read more about how to detoxify from toxin exposure here. If you are currently pregnant or looking for options for your child, talk to your healthcare professional for options.

Next Steps

I hope these tips will help you to improve your or your child’s autism symptoms. If you want to learn how to improve autism, I invite you to schedule a consultation with me here to see if you can benefit from the strategies listed in this article. My fellowship with MAPS (Medical Academy for Pediatrics Special Needs) has advanced my understanding of how to assist the autism community, and families with this diagnosis.

If you are dealing with any chronic health issues, for advice on how to improve your nutrition and health, I welcome you to start a functional medicine consultation with me for further personalized guidance. You may book your consultation here

Learn more about working with Dr. Gannage