The Scottish river with the UK's highest levels of dangerous 'forever chemical' TFA - and the one without it

Only one waterway out of 14 tested in Scotland did not contain traces of a potentially harmful chemical, a study has revealed.

Researchers from York University studied samples from 32 rivers across all four of the UK’s nations, with a total of 14 tested north of the Border.

A general view of buildings next to the River Ness | Getty Images

And the River Ness was the only waterway out of all those tested that did not show traces of trifluoroacetic acid (TFA).

The River Ness, which stretches only over about six miles, starts at Loch Dochfour, at the northern end of Loch Ness, and flows towards Inverness before ultimately emptying into the Moray Firth.

A total of 98 per cent of the 54 sites tested were found to be contaminated with TFA.

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TFA, commonly referred to as a “forever chemical”, typically forms by the degradation of pesticides, pharmaceuticals and refrigerants. There are growing concerns about the health risk for people given the levels of the chemical detected in drinking water supplies. The chemical has also been found in wine, food, human blood and breast milk.

The analysis of samples taken overall from Scottish rivers was far from positive.

One sample, taken from the River Kelvin in Glasgow, produced the second-highest value of TFA ever recorded in surface water globally. Only a river monitoring study in Germany had returned a higher chemical value.

The research was funded by environmental charity Fidra. The goal was to find out how much TFA could be found in surface water across the UK, and compare levels to the degree of contamination found in other countries.

Alistair Boxall, professor of environmental science at the University of York who carried out the research, told the BBC: "We will all be drinking water containing TFA every day, so we'll be exposed throughout our lifetime. It's that long-term, low level exposure that is the big concern."

The University of York is ranked top in Yorkshire, keeping the same position from last year. It is ranked 12th overall in the UK, with an overall score of 788.

Fidra said the UK study had shown average TFA concentrations were at the higher end of the global scale when compared to similar studies. The organisation said the widespread detection of the chemical showed the urgent need for source control.

Fidra’s report said: “While the study is extensive compared to many other investigations, examining numerous surface waters across the UK and throughout all seasons, further work is recommended in regions of the UK not covered to gain a wider picture of the risks of this molecule to UK waterbodies.”

Andreas Hensel, president of the German Federal Institute for Risk Assessment, said: "Currently, there are no expected adverse health effects from consuming water or food contaminated with TFA.

“The new classification is an important step in preparing further measures to ensure that this remains the case in the future.”

Water UK, which represents the UK's water companies, said in a statement: "We want to see PFAS, including TFA, banned and the development of a national plan to remove it from the environment which should be paid for by manufacturers."

Helmut Burtscher-Schaden, environmental chemist at Austrian environmental organisation Global 2000, has previously said: “We are likely ingesting significantly more TFA through our diet than previously assumed. Urgent action is needed to stop further TFA emissions into the environment.”