Harmful chemicals have been detected in everything from clothes to frying pans after manufacturers have tried to hide the dangers they pose for three decades.

Companies were first informed about the health risks associated with the chemicals ‘per- and polyFluorinated Substances (PFAS)’ in 1961; however, they did not take action until the 1990s.

A study conducted by scientists at the University of California has found a link between PFAS chemicals and liver enlargement, poisonings and birth defects in children.

Despite the severe health risks, business executives of the chemical manufacturers DuPont and 3M decided to ignore the dangers and carried on using the toxic substances.

PFAS chemicals have been found in multiple products, such as period underwear, pots, pans, carpets and children’s toys, as well as fabrics and paints.

New data shows that approximately 97% of people living in America have these toxic compounds in their bloodstream.

Once in the blood, PFAS chemicals can affect vital organs and damage DNA – increasing the risk of cancer.

Experts have said that these substances should be handled with “extreme care and contact with the skin should be strictly avoided.”

During the study, a team of academics analysed a variety of DuPont business documents on PFAS chemicals.

Two of the eight pregnant DuPont factory workers in 1980 gave birth to babies with deformities, the analysis shows.

In response, the company said: “We know of no evidence of birth defects caused by PFAS at DuPont,” and claimed that the chemicals were as dangerous as table salt.”

After being faced with lawsuits in 1998 and 2002, the manufacturer published studies on what the industry knew about PFAS that the public did not.

Gynecologist, Dr Tracey Woodruff said: “These documents reveal clear evidence that the chemical industry knew about the dangers of PFAS and failed to let the public, regulators, and even their own employees know the risks.

“As many countries pursue legal and legislative action to curb PFAS production, we hope they are aided by the timeline of evidence presented in this paper. This timeline reveals serious failures in the way the US currently regulates harmful chemicals.”

A DuPont representative said: “We have already reduced our use of PFAS over the past three years through ongoing research and development and will continue to innovate new solutions for customers.”

The study was published in the journal Annals of Global Health.

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