A study has found that chemicals in hundreds of everyday items gather in the liver, which can cause serious health problems.
Per- and polyfluoroalkyl substances, also known as PFAs, are man-made chemicals used to make products water, stain and grease-resistant.
They are also called 'forever chemicals' because they break down very slowly, causing them to build up in the body over time.
PFAs have been linked to a long list of health conditions, including cancer, asthma, raised cholesterol, high blood pressure and thyroid disease.
The study found evidence the chemicals build up in the liver, where they can cause disease.
“Experimental evidence indicates that exposure to per-and polyfluorinated substances (PFAS), a class of endocrine-disrupting chemicals, has the ability to promote metabolic changes that can result in fatty liver,” said the authors of the study, which was published in Environmental Health Perspectives.
Fatty liver disease is caused by the storage of extra fat in the liver. It does not cause a serious issue in everyone, but it can lead to liver damage.
“The stable chemical properties that make PFAs ideal for industrial use also allow them to persist and accumulate in the environment, which is of concern because of the potential for long-term human health effects," the authors said. The study was led by researchers at the University of Southern California, Los Angeles.
With thousands of types of PFAs, almost everyone is exposed to them at some stage.
Previous studies have shown PFAs are present in the blood and all the body organs tested, including the heart, liver, bones and muscle.
“These chemicals can cause liver and kidney damage, impair male fertility, affect hormones such as oestrogen, testosterone and cortisol,” said Dr Aswin Pankajakshan, specialist in endocrinology, diabetology and metabolic disorders at NMC Royal Hospital in Dubai.
Significant sources of exposure include unfiltered drinking water, as well as food, the air and early life placental or breast milk, experts said.
“It can go to any gland and cause many problems,” said Dr Ihab El Tayeb, consultant in endocrinology at International Modern Hospital Dubai.
“It can affect foetal development during pregnancy, because it is in food and beverages consumed. It’s also in canned food. That’s why we are all exposed.”
People can limit their exposure by washing fruit and vegetables before eating them, and choosing organic produce, if possible.
Non-stick pans should be replaced with ceramic-coated cookware.
“Do not use microwaves [so] much, especially with plastic food containers,” said Dr El Tayeb.
“Also avoid canned and processed food if you can. And make most of your food at home. Use a water filter if you can.”
Experts say they pose a problem because they can mimic natural hormones in the body.
“Usually natural hormones work by going to a receptor in a specific organ and then their work starts,” said Dr El Tayeb.
“This endocrine disruptors, sometimes it mimics the hormones. It is cheating the body.
"So they go to the receptor to work instead of the original hormone. And when the natural hormone comes it cannot work.”
A separate study, published in the Environmental Science and Technology journal, found about 60 per cent of children's clothing, fabrics used in pillows, bedding and furniture, sometimes even with green certification, were found to contain PFAs.
Potential health effects of PFAs
PFAs have been used in many products worldwide since the 1950s, according to The Centres for Disease Control and Prevention.
PFOA (perfluorooctanoic acid) and PFOS (perfluorooctanesulfonic acid) are probably the best known, said Dr Pankajakshan.
PTFE (polytetrafluoroethylene) is used as a coating for non-stick pots and pots. When heated at high temperatures, utensils coated in the substance release toxic fumes that cause mild to severe toxicity.
“PTFE is also found to be having carcinogenic potential and also disrupt hormonal balance and affect foetal development,” Dr Pankajakshan said.
PFOA is used in carpeting, upholstery, apparel, floor wax, textiles and firefighting foam. It resists heat, water, stains and grease. It lasts a long time, even in people. Studies have shown high levels of exposure may cause testicular and kidney cancer.
PFOS is used to make Scotchguard water repellent. The chemical has been shown to be toxic to fertility, the thyroid, the immune system and kidneys in laboratory animals and in vitro human systems.