By Basant El-Faramawy
A Chinese study monitoring Mount Everest's northern slope has found that the mountain receives a year-round supply of airborne microplastics and nanoplastics. These tiny particles, less than 5mm in length, have also been detected in human arteries, lungs, placental tissue, brains, livers and bowels, raising concerns about both environmental and public health impacts.
Microplastics pervasive in environment and human body
Microplastics are now found everywhere from ocean depths to soil, water supplies and the fish we eat. Research has identified them in almost every human organ, including blood, lungs, placental tissue and the brain. Scientists warn the particles may induce inflammation, DNA damage, hormone disruption and potentially increase the risk of heart attacks.
Health risks from microplastic exposure
A 2024 study published in the New England Journal of Medicine by Italian researchers found microplastics in carotid artery plaques of people with early-stage cardiovascular disease. Over three years, those with microplastics in their plaques had a 4.5-fold greater risk of stroke, heart attack or sudden death. A 2025 study in Nature identified microplastics in human brain tissue; individuals diagnosed with dementia had up to 10 times more plastic in their brains than those without the condition.
How microplastics enter the body
Humans absorb microplastics through food, water, juices and the air we breathe. Dr Maria Knobel, medical director at Medical Cert UK, said exposure occurs by eating, drinking and inhaling fibres and particles from indoor dust, with possible minor skin contact. Once inside, particles can reach the bowel, liver and other major organs.
Impact on digestive system and liver
The bowels are a primary destination for ingested microplastics. Professor Stephen Patrick, Associate Professor in Medical Imaging at UCL, explained that healthy bowels likely block most particles, but conditions like inflammatory bowel disease or alcohol-related permeability allow more microplastics to pass through, creating a vicious cycle where microplastics worsen disease symptoms. Research on liver cirrhosis also found increased microplastics in damaged liver areas, though causality remains unclear.
Microplastics as carriers for other chemicals
Plastic particles act as sponges for hydrophobic chemicals in water sources, concentrating substances such as antibiotics, metabolic waste and banned compounds like BPA. When ingested, these chemicals are released into the body, potentially disrupting hormones and reproductive health.
Reducing exposure
While completely avoiding microplastics is impossible, experts recommend not microwaving food in plastic containers. Dr Knobel cited a 2023 lab study showing microwaving plastic baby-food containers released up to 4.22 million microplastics and 2.11 billion nanoplastics per square centimetre after three minutes. Another study linked higher microplastic levels in stool to frequent consumption of takeaways and ready meals packaged in plastic. Using glass or ceramic containers for reheating is advised.
