The impact of microplastics on human brains: an exploration
In recent years, the world has seen a significant increase in the production of plastic, with the amount doubling since the year 2000 and projected to triple by 2060. This ubiquitous material is now a key issue in the world's first plastic pollution treaty, as it has been found everywhere, from the air we breathe to the food we consume and even in our bodies.
A study published in the prestigious New England Journal of Medicine last year found a link between microplastics building up in blood vessels and an increased risk of heart attack, stroke, and death in patients with a disease that clogs arteries. The study, which tested brain tissue from individuals who died in the US state of New Mexico in 2016 and 2021, detected the equivalent of a plastic spoon's worth of microplastics in the brains of the subjects.
However, it's important to note that other researchers have urged caution about the study, stating that the speculation about the effects of microplastics on health exceeds the available evidence. This is not an uncommon sentiment in the field of microplastics and nanoplastics in human health, which is rapidly growing but still emerging.
Experiments have been carried out on mice, including a study in Science Advances in January which detected microplastics in their brains. Chinese researchers have also found that microplastics can cause rare blood clots in the brains of mice by obstructing cells.
While definitive causal evidence in humans remains limited due to the novelty and complexity of the issue, current research—from experimental, animal, and early human studies—suggests that micro- and nanoplastics pose real health risks through multiple biological pathways. Major effects seen or hypothesized include oxidative stress, inflammation, endocrine disruption, DNA damage, and potential organ toxicity.
Humans are continually exposed to microplastics via food, water, air, and consumer products. An average person may ingest about five grams of plastic weekly. These plastics contain additives linked to cancer, hormone disruption, reproductive and cognitive impairments, especially concerning for vulnerable populations including children and pregnant women.
Research highlights environmental justice issues where marginalized groups face increased exposure and health risks along the plastic lifecycle. Scientists emphasize the need for improved materials to reduce microplastic generation and for expanded interdisciplinary studies connecting environmental, animal, and human health impacts.
Despite the ongoing investigations, the World Health Organization found in a review in 2022 that the "evidence is insufficient to determine risks to human health" from microplastics. However, many health experts have cited the precautionary principle, stating that the potential threat microplastics could pose requires action. A report on the health risks of microplastics by the Barcelona Institute for Global Health states that "policy decisions cannot wait for complete data".
In conclusion, while the full extent of the health risks associated with microplastics is still under investigation, the current evidence strongly suggests that these tiny particles pose real health risks. As the world continues to grapple with the plastic pollution crisis, it's crucial to prioritise research into the health impacts of microplastics and take steps to reduce our exposure to these harmful substances.
[1] Environmental Science & Technology [2] Environmental Health Perspectives [3] Science Advances [4] Nature Reviews Materials
- Given the increasing rate of microplastics in our environment, it's concerning to find that these particles may pose real health risks, as evidenced by studies published in Environmental Science & Technology and Science Advances, which have detected microplastics in food, water, air, and even in our bodies.
- In light of growing evidence about the health impacts of microplastics, health experts often refer to the precautionary principle, emphasizing that policy decisions cannot wait for complete data, as stated in a report by the Barcelona Institute for Global Health.
- On the other hand, it's important to note that while microplastics may have potential health risks, the World Health Organization found in a review that the evidence is insufficient to determine risks to human health. However, this does not dampen the call for interdisciplinary studies connecting environmental, animal, and human health impacts, as highlighted in Environmental Health Perspectives and Nature Reviews Materials.
- As the world works towards addressing climate change and promoting health-and-wellness, it's crucial to consider the impact of microplastics on mental-health, given the stress and anxiety associated with ongoing environmental degradation, as well as the need for improved materials to reduce microplastic generation in the realm of environmental-science.
