Scientists discover rising levels of microplastics in human brain

Brain samples from 2024 showed 50% more microplastic contamination compared to 2016, according to research published in Nature Medicine that suggests a potential connection to dementia.

University of New Mexico researchers examined post-mortem brain tissue from 52 individuals, finding higher concentrations of microplastics in the brain compared to other organs such as kidneys and liver.

The study revealed elevated microplastic levels in the brains of 12 people diagnosed with dementia, compared to those without the condition, though scientists emphasise more research is needed to confirm any direct link.

Most microplastics found in the examined brains were polyethylene, widely used in food and beverage packaging, shampoo bottles, and recycling bins.

The research showed no correlation between microplastic presence and age, gender, or ethnicity of the deceased subjects.

Microplastics, defined as plastic particles smaller than five millimetres, enter the human body primarily through inhalation and ingestion. They have previously been detected in the liver, intestines, kidneys, blood, and placenta.

The particles originate from two main sources: primary microplastics intentionally manufactured for products like fertilisers and cosmetics, accounting for 30% of marine microplastic pollution, and secondary microplastics from the degradation of larger items such as plastic bags and bottles, responsible for 70%.

European data indicates that approximately 145,000 tonnes of microplastics are used annually for industrial purposes, with 42,000 tonnes ending up in the environment each year.

The European Commission banned 78 types of microplastics in September 2023 and developed guidelines for managing the issue, following growing concerns about their prevalence in food products and drinking water.

Recent studies have found microplastics in 90% of animal and plant protein samples, with research also detecting significant levels in common food items including rice, Himalayan pink salt, and sugar.