Harmful “forever” chemicals linked to cancer and heart disease are so widespread that foetuses are being exposed to them before birth, scientists say.
“Forever” chemicals are those made for products such as non-stick pans, clothing, food packaging, carpets and firefighting foam.
Every study published in the past five years that looked at the effects of such chemicals reported detection of them in umbilical cord blood, researchers found.
A team from the Environmental Working Group, an American non-profit organisation, looked at 40 studies examining the presence and health effects in cord blood of perfluoroalkyl and polyfluoroalkyl substances (PFAs).
They are known as “forever” chemicals because they don’t break down in the environment, remaining a threat indefinitely.
They have been linked to cancer and have been found even in the most remote parts of the world, making rainwater unsafe to drink.
Humans may be exposed to “forever chemicals” through contaminated food and water, and inhalation of dust and fumes from consumer products.
A developing foetus may be exposed through the umbilical cord and placenta, and babies through breastfeeding.
Exposure to them is also linked to diabetes, obesity, thyroid disorders, kidney disease, cardiovascular disease and lower birth weight. Studies have found they may also lead to childhood respiratory tract infection and a type of eczema.
All 40 studies that the researchers examined had found a wide range of PFAs in the blood – about 35 in all.
Sixteen studies found links between chemical exposure in cord blood and changes in vital body molecules called cord blood lipids, as well as harm to foetal and childhood development.
At least 14 studies found a link between the toxins in cord blood, detection of the chemicals later in childhood or increased risk of health effects in adulthood – or all three.
The studies, published in peer-reviewed journals, were conducted in the US and 11 other countries, including Brazil, China and Japan.
Tests from the US Centers for Disease Control and Prevention have found that nearly all Americans have two of the most widespread PFAS in their blood.
The chemicals may be found in people’s fluids or tissues, including of the brain, liver, lung, bone, kidney, and breast milk.
People have been advised to avoid products with long-lasting, non-stick and waterproof properties and avoid fast food because of grease-resistant coatings on packaging.