Is UK tap water contaminated by “forever chemicals”?

With the recent concern over pollution in our rivers, it’s surprising that the presence of toxic “forever chemicals” in our drinking water remains undiscussed. Yet, there is clear evidence that they are present in our water sources and are therefore likely to be in our tap water.

Experts believe the presence of these chemicals in tap water, by raising our cumulative environmental exposure, increases the likelihood of a range of illnesses. It appears that we may be experiencing a chronic, but hitherto hidden, public health emergency.

Manmade industrial chemicals, known collectively as PFAS or “forever chemicals”, because they don’t break down in the environment, have been used extensively since the 1940s.

There are approximately 10,000 different types, used in all manner of products—firefighting foams, carpets, textiles, non-stick coatings (such as Teflon), car waxes, electronics manufacturing, plastics and even toilet roll.

When these chemicals enter the environment they accumulate in soil, water, animals and humans. 

As chemist and PFAS expert Roger Klein explains, “The problem with PFAS is that they are toxic, don’t degrade and as you drink them you increase your body burden as they are bioaccumulative.”

Courtesy of Focus Features. The film Dark Waters dramatised the class action lawsuit against DuPont, who polluted drinking water in the US

The issue was publicised in the film Dark Waters, which dramatised litigation against chemical company DuPont, which was polluting drinking water in the US with a harmful PFAS chemical used in the production of Teflon.

The resulting epidemiological studies found that this harmful toxin was in the blood of nearby residents.

Dr Julie Schneider, chemicals campaigner and PFAS lead at CHEM Trust, wouldn’t be surprised if our tap water contains PFAS, as she explains that they’ve been found in “over 90 per cent of the surface water sites tested by the Environment Agency” according to a 2021 report, with that same surface water accounting for 68 per cent of drinking water sources in the UK.

Dr Schneider warns: “The presence of PFAS is very concerning because it contributes to peoples’ continuous exposure to these harmful chemicals, in addition to other daily routes of exposure, such as food and consumer products treated with PFAS (such as waterproof clothes, greaseproof food packaging and certain cosmetics).”

She explains that exposure to the most studied PFAS (such as PFOS and PFOA) has been linked to a vast array of adverse effects, including impacts on the hormonal, immune and reproductive systems, as well as increased risk of developing certain cancers.

Even regarding the newer generation of PFAS, she says “less is known but existing studies show they are equally of concern.”

The UK Government’s Department of the Environment, Food and Rural Affairs (Defra) have stated: “UK drinking water standards are of a very high standard and are among the best in the world. Water companies are required to carry out regular assessments and sampling for PFAS to ensure that drinking water remains safe.”

However, in England and Wales the guidance from the Drinking Water Inspectorate (DWI) is a maximum level of 100ng/l (100 parts per trillion) for any individual PFAS in drinking water, whereas in the EU (and Scotland) the statutory standard is the same value of 100ng/l but for for the sum of 20 PFAS, not just one PFA at a time.

The UK standard could therefore be seen as 20 times less protective than the EU one.

In the US, its Environmental Protection Agency has proposed a maximum level of 4ng/l for PFOS and PFOA individually, so it is 25 times more stringent than the UK one.

Indeed, such is the danger of PFAS to humans that the world’s leading expert on its adverse effects, Professor Grandjean, formerly of Harvard, says his calculations agree with the US EPA that the “only safe exposure is zero.”

He outlines the risks, particularly to children: “Our research identified adverse effects at lower and lower levels of exposure. We currently believe the immune system is particularly vulnerable, and we can see that children (and adults) respond less favourably to vaccinations and there is a risk that the vaccination may not work (that is, by generating sufficient amounts of specific antibodies).

"We also know of increased risks of metabolic disease, such as diabetes, obesity and thyroid dysfunction, and decreased fertility, lowered birth weight, and decreased skeletal mineralisation in children.”

Testing for PFAS varies across England, Wales and Scotland—and England's standards may fall short

Across the UK, privatised water companies have been given responsibility for identifying risks and sampling water supplies for contamination with the DWI (a section of Defra) playing the role of “independent” regulator in England and Wales, and the Drinking Water Quality Regulator (DWQR) doing the same in Scotland.

However, Dr Schneider points out that there is a lack of transparency regarding the presence of PFAS in drinking water. Indeed, it proved impossible to get very precise information on the scale of contamination during the course of research for this article.

In England and Wales only 47 PFAS are now routinely tested for, with 20 tested for in Scotland. Moreover, as specified above, the trigger levels are far too high, according to experts. From the limited data available the testing of our drinking water sources appears slow and partial, certainly not in real-time.

When contacted, water company Severn Trent did confirm: “Based on the results obtained from the 47 PFAS compounds sampling, all of our sites sampled to date remain in the lowest risk category Tier 1” (below 0.01ug/l or 10 parts per trillion).

Scotland’s DWQR was similarly unable to give categorical reassurance that PFAS don’t exist in drinking water. It stated: “There is currently very limited data to determine whether there is an issue with drinking water in Scotland.

"Early indications are that most samples are well within the new standard, and the upland location of most of Scotland’s water sources should make them less vulnerable to contamination from man-made sources.”

The DWQR went on to admit: “No specific treatment for PFAS is currently in use in Scotland. The UK water industry is evaluating the effectiveness of various treatment processes for PFAS removal.”

What is becoming clear is that evaluating, then remedying, this evolving public health emergency is going to take a huge amount of money and effort. It is unlikely any private water company will be in a position to do the work alone without government help.

This will, in turn, likely cost billions of pounds in taxpayers’ money and require government legislation to immediately ban the routine use of these toxic chemicals and set a statutory limit for PFAS in UK drinking water.

One long-standing critic of privatisation of water in the UK is Jeremy Corbyn, ex-leader of the Labour Party, who comments: “The scale of pollution in drinking water sources is deeply alarming.

"The chemical crisis is yet another demonstration of the failures of privatisation which has allowed unaccountable companies to prioritise profit over public health.

"We need to bring water back into democratic public ownership, so that we can ensure everyone has access to safe and clean water.”

Read more: How to make your home healthier

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