A chemical found in tap water that’s been linked to cancer could also raise Ievels of harmful cholesterol, a study has suggested.
Called perfluorooctanoic acid, the substance has long been used in products such as frying pans and food packaging to stop materials like plastics sticking together.
But it is part of family of substances dubbed ‘forever chemicals’ — known to persist in both the environment and inside people’s bodies for years without breaking down.
Now, US scientists have suggested the compound — which has previously been found in UK tap water supplies — could raise cholesterol levels, raising the risk of heart disease and strokes.
In the study, the scientists fed mice a high carbohydrate and fat diet, the equivalent to that consumed by the average modern American, and drinking water containing various levels of perfluorooctanoic acid.
The rodents were fed water with perfluorooctanoic acid doses ranging from 0.5, 1.4 or 6.2 mg per litre, for 14 weeks, to achieve an exposure level previously recorded in people.
Analysis found mice fed the medium and highest amounts of the chemical saw an increase in levels of LDL cholesterol in the blood and liver — the type most associated with health risks, often referred to as ‘bad’ cholesterol.
LDL cholesterol is a fatty substance that can accumulate in the blood vessels, forming deposits that can interfere with blood flow, risking heart attacks and strokes.
PFAS are found in a swathe of everyday items, from non-stick cookware, clothing, food packaging, carpets, paints, toiletries, and period products
Writing in the journal Archives of Toxicology, the US experts observed that perfluorooctanoic acid appeared to be interfering with enzymes that help the liver eliminate the fatty substance.
‘Approximately one-third of cholesterol is eliminated through conversion to bile [a digestive enzyme] and this pathway represents the major source of daily cholesterol turnover,’ they said.
The scientists noted the chemical appeared to have a stronger impact on cholesterol in female mice, though they added this may be because the rodents drank more water than the males.
They added that further work was needed to explore the implications of perfluorooctanoic acid exposure in humans over long periods of time.
Perfluorooctanoic acid is one of many industrial substances that are commonly referred to as per-and-polyfluoroalkyl substances, or PFAS.
PFAS have previously found in British drinking supplies, in both tap and bottled water.
However, experts have found boiling the water, or using simple filtration jugs commonly available in stores, reduces PFAS concentration in water by up to 90 per cent.
Concerns about the chemicals have been growing for years, and while some have been banned in certain countries, they remain widely used.
They are found in a swathe of everyday items, from non-stick cookware, clothing, food packaging, carpets, paints, toiletries, and period products.
Results from the Our Future Health project demonstrating levels of high cholesterol in the population based on a sample of 227,592 volunteers. Source: Our Future Health
Studies have linked exposure to a host of health issues including cancers of the kidney and testicles, lower immune response, impaired liver function, decreased birth weight and infertility.
While these links are not definitive, part of the concern is due to how widespread PFAS exposure is and how long they persist in the environment.
The UK Government currently sets a limit of 0.1microgram per litre for PFAS in UK drinking water.
An official report recorded one occasion in 2023 when a drinking water sample for England was above this level.
Patients have been urged for years to keep an eye on cholesterol and reduce their risk by eating fewer fatty foods, exercising more and cutting down on smoking and drinking.
Medications like statins, a daily pill taken by about 8million patients, can also be prescribed to help lower cholesterol.
Cardiovascular disease causes about a quarter of all deaths in the UK, some 170,000 deaths each year.
That about 480 deaths a day, or one every three minutes according to the British Heart Foundation.
