Microplastics as Bioaccumulation Without Borders (Part 2): Diagnostics, Reducing Burden, and Environmental Impacts of Wildfires

By Sara Szal MD | July 8, 2025 |

Microplastics are tiny plastic particles—less than 5 millimeters in diameter—that contaminate virtually every ecosystem on Earth, from ocean streams to human bloodstreams. These synthetic fragments, shed from consumer products, packaging, clothing, and industrial processes, are small enough to be inhaled, ingested, or absorbed through the skin. Their ability to bioaccumulate, cross biological barriers, and carry endocrine-disrupting chemicals makes them a growing concern for your health. Emerging research suggests microplastics may contribute to inflammation, oxidative stress, hormonal disruption, and even neurodevelopmental and reproductive risks—raising urgent questions about their long-term effects on both individual and planetary health.

In Part 1 of our exploration into microplastics, we covered what they are, their widespread presence, the potential health implications suggested by current research, and the populations most at risk. Now, let’s shift our focus to the challenges of diagnosis, strategies for reducing our exposure, and how specific environmental issues like wildfire can significantly amplify microplastic levels.

Diagnostic Tests for Microplastic Exposure Are Limited

There are currently no reliable, validated clinical diagnostic methods for directly detecting clinical symptoms specifically attributable to microplastic exposure in high-risk populations such as infants, children, or occupationally exposed adults. Clinical evaluation remains symptom-driven, focusing on standard workup for gastrointestinal, respiratory, or immune-related complaints, as there are no pathognomonic signs or symptoms unique to microplastic exposure.

While doctors can’t diagnose microplastic-related illnesses, scientists can detect microplastics in human samples like blood, stool, placenta, and lung tissue. They use highly advanced lab techniques such as:

  • Fourier-transform infrared spectroscopy (FTIR)
  • Raman spectroscopy
  • Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS)

However, these are research tools and are not available in clinics for routine diagnostic use. Even though studies show microplastics are present in our bodies, we don’t yet know if these levels directly cause specific health issues or what a “safe” level might be.1

If you’re experiencing symptoms like digestive problems, breathing difficulties, immune system issues, fatigue, or dizziness, your doctor will follow standard diagnostic procedures to find the cause.

Right now, if a doctor suspects a microplastic-related illness, it’s based on your history of exposure and ruling out other possible causes, not on a specific test or biomarker.

How Might We Reduce Microplastic Load?

Governments and organizations are taking action to cut down on plastic use, which in turn reduces microplastics in our environment.

  • Policy and Regulations: Things like bans, taxes, and restrictions on single-use plastics have been very effective. For example, countries that have banned or taxed plastic bags have seen an 8% to 85% drop in their use, leading to less plastic pollution.
  • Community and Industry Efforts: Better waste management, higher recycling rates, and the use of biodegradable plastics all help stop microplastics from getting into the environment. These “upstream” efforts (tackling the problem at its source) are proven to significantly lower the amount of microplastics in our surroundings, which should lead to less human exposure. However, we still need more direct research on the health benefits.

What to Do at Home to Reduce Microplastics

You can make a difference in your daily life to reduce your family’s exposure to microplastics, especially when it comes to food and baby care.2

  • Choose Alternatives to Plastic:
    • Avoid bottled water as much as possible.
    • Minimize packaged foods.
    • Use non-plastic baby bottles and food containers.
  • Smart Food Preparation:
    • If you’re preparing formula for infants, don’t use plastic bottles.
    • Avoid heating food in plastic containers, especially for babies and young children.
  • Be Aware at Home: Pregnant women and families with young children should be extra mindful of where plastics are used in food preparation and storage.
  • Workplace Safety: If your job exposes you to microplastics, use personal protective equipment and make sure your workplace has proper ventilation and controls to reduce inhalation and skin exposure.

Why More Research is Needed

While these strategies make sense and are based on reducing exposure, we don’t yet have direct medical evidence proving that these actions specifically reduce microplastic-related health problems or symptoms. Most recommendations come from what we know about environmental science and toxicology, rather than from human studies that show improved health after making these changes. We need more research to:

  • Standardize how we measure microplastic exposure.
  • Conduct long-term studies on health outcomes.
  • Evaluate how effective specific actions are at reducing both microplastics in our bodies and the health risks they might pose.

In short, the best ways to reduce microplastic exposure, especially for vulnerable groups, are strong government policies, better waste management, and making personal changes to use less plastic, particularly with food and baby products. These approaches are known to reduce environmental pollution and likely lower our exposure, but we still need more scientific evidence to confirm their direct health benefits.3

The Impact of Large Fires on Microplastic Exposure

Large fires, like those seen in Los Angeles, don’t just burn trees and homes; they also dramatically boost the amount of microplastics in our environment. The intense heat from these fires acts like a super-accelerator, breaking down plastic waste (e.g., synthetic textiles, personal protective equipment, building materials) into tiny microplastics and even smaller nanoplastics. These microscopic particles then get released into the air and spread far and wide.4

Experimental studies simulating bushfire conditions have demonstrated that burning plastic-containing items, such as PPE masks and printed materials, results in the emission of both microplastics and nanoplastics, which can then be dispersed by wind and deposited over wide areas. The combustion process can fragment plastics into smaller particles, increasing their potential for inhalation and environmental distribution.

What’s more, these fire-generated microplastics aren’t just smaller; they can also be more toxic. The heat can change their physical and chemical properties, giving them a larger surface area and causing them to release more harmful chemicals, like antimony. This makes them potentially more reactive and dangerous to both the environment and living beings.

Certain groups are at a higher risk of inhaling or ingesting these airborne microplastics after a large fire:

  • Infants and Children: Their developing bodies and higher breathing rates make them more vulnerable.
  • Pregnant Women: There’s concern that microplastics could cross biological barriers and impact fetal development.
  • Adults with High Exposure: This includes first responders, clean-up crews, and anyone living in areas heavily affected by the fire.

These airborne microplastics can travel long distances and even accumulate inside homes, increasing the risk for those already vulnerable. Inhaling microplastics is a major concern, as they can settle in the lungs, potentially causing inflammation, cellular stress, and worsening existing breathing problems.

Conclusion

Microplastics are an emerging and underappreciated variable in the longevity equation. These microscopic particles—found in placentas, infant feces, blood, and even lung tissue—are not inert. Early mechanistic studies and animal models suggest they may contribute to inflammation, oxidative stress, endocrine disruption, and translocation across biological membranes. While we don’t yet have high-confidence, longitudinal human data linking microplastics to disease endpoints, the plausibility is high enough—and the exposure widespread enough—to warrant caution.

Certain populations may be disproportionately affected: infants, children, pregnant individuals, and those in high-exposure environments. For these groups, the potential dose-response curve may be steeper due to immature or compromised detoxification systems. And while the average person can’t control ambient environmental levels, they can reduce cumulative exposure through targeted choices—particularly in food storage, filtration, and personal care products.

We lack rapid, clinically validated diagnostics to assess microplastic burden in humans. But the absence of measurement tools should not be mistaken for absence of effect. In the context of risk reduction, the precautionary principle applies.

As with many threats to long-term health, the path forward is probabilistic, not deterministic. But as we build a more precise framework for understanding aging, microplastic exposure is one variable we can’t afford to overlook. Ultimately, to protect ourselves and future generations, we need to know more about microplastics and how to reduce our exposure. It’s a hidden challenge, but one we’re starting to bring into the light.

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