The link between environmental toxins and cognitive disorders

By Jules Murtha | Fact-checked by Barbara Bekiesz
Published August 22, 2022

Key Takeaways

  • Cigarettes and e-cigarettes contain substances that can impair memory function and retention in users.

  • Research suggests that patients with autism spectrum disorder (ASD) have difficulty eliminating toxic metals, which can lead to an accumulation of metals that may magnify symptoms of ASD.

  • Patients who are exposed to bacteria, viruses, and molds that produce biotoxins and metals may experience cognitive decline and pathophysiology related to AD.

The term environmental toxins may conjure up images of nuclear plants and other industrial machinery that may seem irrelevant in your patients’ day-to-day lives. However, humans often come into contact with environmental toxins through cars, cigarettes, or certain makeup items, among other products.

Emerging research suggests that some toxins may lead to cognitive impairments and the development of brain health issues among patients.

Doctors can encourage patients to be aware of what they consume or come into contact with that may pose dangerous risks.

Cigarettes, e-cigarettes, and memory impairment

The negative effects of cigarette smoke on the lungs and pulmonary function is common knowledge. But brain health is also at stake when patients are exposed to cigarette smoke and e-cigarette vapor.

According to a study published by Frontiers in Molecular Neuroscience, cigarette smoke exposure has a direct influence on memory retention.[] Researchers came to this finding by testing mice for working and spatial memory retention with the use of objects.

Results showed that the mice that were exposed to cigarette smoke couldn't discern between known and novel objects throughout the retention phase. Mice that didn’t undergo cigarette smoke exposure, on the other hand, could successfully tell the difference.

Along with memory retention issues, mice that were exposed to cigarette smoke also showed signs of a compromised hippocampus characterized by “changes in astrocyte density as well as a reduction in synaptophysin and dendritic spines,” according to the authors.

E-cigarettes (vapes) pose similar risks to patients who use them.

A study published by Brain, Behavior, and Immunity described the cognitive changes in mice that were exposed to tobacco-flavored e-vapor from nicotine-containing (18 mg/L) or nicotine-free (0 mg/L) e-fluids.[] All mice were exposed twice a day over the course of 6 weeks.

Researchers found that exposure to e-vapor led to significant impairments in short-term memory function independent of diet and the presence of nicotine. The mice also experienced systemic inflammation.

Further research is needed to establish concrete conclusions about e-vaping and cognitive dysfunction in humans. For now, animal studies suggest a strong connection between the two.

Heavy metal exposure and ASD

In addition to cigarette smoking and vaping, exposure to heavy metals may also prove dangerous to brain health—especially to patients with autism spectrum disorder (ASD).

An article published by Neuroscience and Biobehavioral Reviews states that children with ASD have a harder time eliminating toxic metals, including aluminum, lead, and cadmium, among others.[]

Because of this, they tend to accumulate higher concentrations of the metals they’re exposed to. Enzyme dysfunction, impaired cell signaling processes, and oxidative stress–induced apoptosis—all of which are hallmarks of ASD etiology—may surface due to heavy metal exposure.

The accumulation of heavy metals in a patient’s body may also exacerbate existing ASD symptoms. Environmental factors, therefore, could play a role in the severity of this neurodevelopmental disorder.

Environmental toxins and AD

Another cognitive disorder that could worsen as a result of exposure to environmental toxins is Alzheimer disease (AD).

According to an article published by Neurochemistry International, bacteria, molds, and viruses that produce metals and biotoxins may trigger a decline in cognitive function in individuals exposed to them.[] This can contribute to the development of neurodegenerative diseases like AD.

The authors elaborated on the mechanisms behind the pathophysiology associated with AD due to exposure to some toxins, writing, “Toxins may contribute to the pathology of the disease through various mechanisms such as deposition of amyloid-beta (Aβ) plaques and tangles in the brain, induction of apoptosis, inflammation, or oxidative damage.”

While it’s unrealistic to expect any person to steer clear entirely of environmental toxins, you may encourage patients to maintain an awareness of what they consume or use.

An article published by the Cleveland Clinic gave some suggestions for how consumers can avoid environmental toxins in everyday life.[] They can check product labels, for example, and choose products that are phalate-free, paraben-free, and BPA-free.

Eating organic food (to avoid pesticides) and drinking tap water instead of bottled (to avoid chemicals and bacteria) may also decrease risks associated with some environmental toxins.

What this means for you

Patients who are exposed to certain environmental toxins including e-cigarettes, cigarette smoke, and heavy metals may develop cognitive impairments. Doctors can advise patients to exercise caution regarding BPA, phthalates, parabens, and other chemicals they may encounter in common, everyday products.

Read Next: These sources of poison could be in your backyard
Share with emailShare to FacebookShare to LinkedInShare to Twitter