Bangkok: Microplastics and nanoplastics, tiny particles of plastic, are increasingly being recognized as a global environmental and health concern, as they have been found almost everywhere on Earth, including in animal feed in the UK.
According to Thai News Agency, microplastics are defined as plastics smaller than 5 millimeters, while nanoplastics are even smaller, less than 1 micron. These particles have become part of the Earth's water cycle, leading to their widespread presence.
Megan Wolf, the executive director of the Physician and Scientist Network Addressing Plastics and Health, explains that microplastics are now present in the water cycle, rising into clouds with evaporated water and returning to the ground in snow and rain. This widespread distribution has led to finding microplastics almost everywhere, including within various organs of the human body. While the body can expel larger microplastics through natural mechanisms like coughing, smaller nanoplastics pose a greater risk as they can penetrate deeply into the lungs and spread through the bloodstream.
Research is ongoing to understand the health risks associated with microplastics. While a correlation between microplastic exposure and various diseases has been observed, it remains unclear whether microplastics directly cause these health issues. A 2024 study in the New England Journal of Medicine associated microplastics in arterial plaque with increased risks of heart attack and stroke. Similarly, a 2025 study in Nature Medicine found that individuals who died in 2016 had lower microplastic levels in their liver and brain compared to those who died in 2024, with high levels also noted in dementia patients.
The challenge in researching microplastics' health effects lies in the difficulty of conducting controlled studies on humans, as it is impossible to create a control group free from plastic exposure. Thus, existing research often identifies correlations rather than definitive causal effects.
Microplastics have also been detected in 75% of pet food brands in the UK, as discovered by researchers from the University of Sussex and Exeter in June 2026. This contamination was initially observed in the feces of hedgehogs, traced back to various types of pet food. Out of 38 brands tested, 29 were found to be contaminated, with dry pet food containing higher microplastic levels, although wet pet food is more commonly consumed by pets.
In light of these findings, the medical community advocates for minimizing plastic use to reduce microplastic exposure. Simple actions, such as avoiding plastic bottles and reducing the use of plastic cutlery, can help mitigate potential health risks.