Microplastics are silently hijacking our brains

Microplastics Contain Human Brains – The Unknown Effect

Tiny plastic fragments have been found in the brains of human donors, but whether they are truly harmful remains unproven.

Widespread Presence in the Body

• From the mountain’s summit to ocean depths, microplastics have infiltrated the air we breathe and the food we consume.
• They have also colonised lungs, hearts, placentas, and breached the brain’s protective barrier.

Emerging Global Concern

The growing ubiquity of microplastics is now a decisive issue in drafting the world’s inaugural plastic‑pollution treaty. The latest UN negotiations will convene in Geneva next week.

Scientific Findings in Brain Tissue

• In February, researchers published a landmark study in Nature Medicine. They tested brain samples from 28 deceased donors in 2016 and 24 donors from last year in New Mexico.
• Microplastics quantity in the samples rose over time.
• Lead toxicologist Matthew Campen told media the equivalent of a plastic spoon’s worth of microplastics existed inside the brains.
• He estimated that 10 grammes of plastic could be isolated from a donated human brain – a quantity comparable to an unused crayon.

Critical Reassessment by Global Experts

• Scottish toxicologist Theodore Henry cautioned that the study should be interpreted cautiously pending independent verification.
• He asserted that speculation about potential health effects had “gone far beyond the evidence”.
• Australia’s RMIT professor Oliver Jones pointed out insufficient data to support firm conclusions at either local or global scale.
• Jones deemed it unlikely that the brain contained more microplastics than those found in raw sewage, contrary to researchers’ estimates.
• He also noted that study participants were healthy before death and that there was no evidence that microplastics caused harm.

Observational Research and Its Limits

Most investigations into microplastics have been purely observational, which cannot establish causation.

Observational Findings

• A 2023 New England Journal of Medicine study linked microplastics accumulation in blood vessels to higher risks of heart attacks, strokes, and death in patients with arterial blockages.
• Mouse experiments, including a 2024 Science Advances study, detected microplastics in their brains.
• China‑based researchers said microplastics caused rare blood clots in mice by obstructing cells – emphasizing the small mammals differ from humans.

World Health Organization Review (2022)

The WHO’s 2022 review concluded the evidence was insufficient to determine risks to human health from microplastics.

Adopting the Precautionary Principle

• Many health experts invoke the precautionary principle, arguing that potential risks demand timely action.
• Barcelona Institute for Global Health warned policy decisions cannot await complete data.
• They suggested that immediate measures—reducing exposure, improving risk assessment methods and prioritising vulnerable groups—can preclude a future public‑health crisis.

Industry Growth and Implications

• Global plastic production has doubled since 2000 and is projected to triple by 2060.
• Increased output amplifies the potential for microplastics to infiltrate ecosystems and human bodies.