Microplastics In Brain? How Environmental Damage Is Harming Human Body

Microplastics have been a burgeoning and pervasive hazard to the environment, which has now become a human health risk. In recent studies, scientists have discovered that microplastics have invaded critical human organs including brain tissue, reproductive organs, placenta, bone marrow, and more. Researchers are now calling for urgent action to mitigate environmental pollution. 

Microplastics Have Infiltrated Brain Tissues

A study by the National Institutes of Health (under the United States government), has found an average of about 0.5% plastic by weight in the brain samples that were taken in early 2024. The paper also found the quantity of microplastics in brain samples from 2024 was about 50% higher than the total in samples that date to 2016. Speaking to the Guardian, scientists broke down the gravity of the situation.

Researchers looked at 12 brain samples from people who had died with dementia, including Alzheimer’s disease. These brains contained up to 10 times more plastic by weight than healthy samples. An examination of the livers, kidneys and brains of autopsied bodies found that all contained microplastics, but the 91 brain samples contained on average about 10 to 20 times more than the other organs. 

Related Study: Microplastics In Semen

In another recent study, microplastics were detected in every human semen sample tested. The study, titled Prevalence and Implications of Microplastic Contaminants in General Human Seminal Fluid: A Raman Spectroscopic Study, provides an in-depth analysis of microplastic presence and its possible effects on semen quality. This discovery raises significant concerns about the potential impact of these contaminants on human reproductive health. 

The research aimed to explore the presence and types of microplastics in semen samples from individuals without occupational exposure to such contaminants. Researchers collected semen samples from 40 participants undergoing premarital health assessments in Jinan, China. Using Raman microspectroscopy, they identified, quantified, and categorized the microplastic polymers. Sperm motility was evaluated through computer-assisted analysis, and morphology was assessed using Diff-Quik staining.

The study's findings highlight the widespread contamination of human bodies with microplastics and suggest potential reproductive health impacts. Despite the observation of sperm abnormalities, the study did not find a direct correlation with specific types of microplastics. However, the differential effects on sperm motility between polystyrene and polyvinyl chloride warrant further investigation.

Other studies have similarly found microplastics in human semen, including research in Italy and China. In animal studies, microplastic exposure has been linked to reduced sperm count, abnormalities, and hormone disruption, highlighting the potential risks to reproductive health.

Key Findings:

1. Ubiquity of Microplastics: Microplastics were detected in all 40 semen samples, with an average of 2 particles per sample, ranging in size from 0.72 to 7.02 micrometres.
2. Prevalent Polymers: Eight distinct polymer types were identified, with polystyrene (PS) being the most common (31%), followed by polyethylene (PE) and polyvinyl chloride (PVC).
3. Sperm Motility and Microplastics: Semen samples exposed to polystyrene showed higher sperm progressive motility compared to those exposed to polyvinyl chloride (43.52 ± 14.21% vs. 19.04 ± 13.46%).
4. Sperm Morphological Abnormalities: While abnormalities were observed, there was no significant association with specific plastic types.

Global Microplastic Pollution

Microplastic pollution is a global issue, with particles found from the highest peaks of Mount Everest to the deepest ocean trenches. People are exposed to these contaminants through food, water, and even air. Recent studies have detected microplastics in human blood, placentas, and breast milk, indicating widespread contamination.

Urgent Need for Further Research

Chinese scientists leading the study emphasise the urgent need for further research to understand the full extent of microplastic contamination and its implications for human health, particularly reproductive health. Sperm counts in men have been declining for decades, and up to 40% of low counts remain unexplained. This study adds to a growing body of evidence suggesting that chemical pollution, including microplastics, could be a significant factor.

Call to Action

The research highlights the need for immediate action to address the rising tide of plastic pollution. Luigi Montano of the University of Rome, who led a related study, calls for global intervention to halt the exponential increase in plastic waste. Over 180 nations are currently negotiating a UN treaty to regulate plastic production and cut pollution.

As Ning Li of Qingdao University and colleagues note, "Understanding the extent of human contamination and its relation to reproductive outcomes is imperative." The potential impact of microplastic pollution on reproductive health could have far-reaching consequences, making it essential to address this issue promptly to prevent further harm to both the planet and human health.