Is your tap water safe to drink?
Could dangerous chemicals in your drinking water be harming your health? Pressure is building on the UK Government to take more stringent action on the levels of so-called “forever chemicals” in our drinking water, amidst growing evidence that they can lead to health problems, increasing the risk of cancer, heart attacks and even birth complications.
Earlier this week, Joe Biden announced a major bid to improve the safety of drinking water supplies across the US by introducing a drastic crackdown on the acceptable levels of polyfluoroalkyl substances (PFAS). Under the new federal proposal, water providers will have to keep PFAS at no more than four nanograms per litre (4ng/l), the lowest level that can be reliably measured.
Politicians and academic experts are now calling for Rishi Sunak to introduce similar restrictions. Right now, the UK’s current drinking water restrictions allow for PFAS levels of up to 100ng/l, 25 times higher than Biden’s proposed limit.
If the new US limit was imposed here, there would be a need for a drastic clean-up of the UK’s water supplies. A recent analysis found that 1,900 samples taken across the country contained levels of these chemicals exceeding 4ng/l .
So how can PFAS affect us, and what can we do about it?
How do these chemicals get into our water?
PFAS encompass around 10,000 different chemicals that are used in various consumer and industrial processes, mainly for their non-stick properties. They are known as “forever chemicals” because they do not break down in the environment, and so over time they leach into our water supply.
“Drinking water is not the only way that these contaminants can enter the human body,” says Vanessa Speight, professor of integrated water systems at the University of Sheffield. “There is significant contamination in soil, food and the environment. The contribution of drinking water to PFAS exposure varies from one person to another.”
What is their impact on our health?
Scientists have spent many years trying to understand the precise health risks of PFAS and the thresholds at which they occur. However, studies have now linked them to a broad range of health issues, ranging from reproductive problems to immune system suppression, increased cholesterol, kidney cancers and fertility problems, particularly in men.
“Reproductive health effects such as decreased fertility, developmental delays in children, and certain cancers are now believed to be linked to PFAS with enough certainty to proceed with regulation,” says Speight.
Is the water in different parts of the UK more chemical-laden than others?
People living in certain parts of the UK are more at risk of being exposed to high amounts of PFAS in their drinking water than others. For example, according to Stephanie Metzger, sustainable chemicals policy advisor at the Royal Society of Chemistry, parts of London are at an elevated risk due to the high numbers of PFAS in the Thames.
“Existing Environmental Agency data shows PFAS hot spots around the country,” she says. “The Thames has the largest number of individual record PFAS substances, though experts are confident there are many more out there that are not currently included in tests.”
Metzger says that there is an urgent need for politicians to invest in better technologies for testing the water in different parts of the country, particularly if we want to set lower limits of PFAS pollution in line with the US.
“The UK needs targeted funding to strengthen its analytical testing capacity,” she says. “Scientists are working on more and more sensitive methods to improve this, but the reality is that, at present, we may not be equipped to test to the threshold being set in the US.”
What can we do about it?
Speight suggests that the best first step for anyone concerned about the levels of PFAS in their water is to ask their water company for the latest sampling results for their particular location. If those measurements exceed 4ng/l, then she recommends considering purchasing a home treatment device, such as a tap-fitted filter or a filter pitcher.
However you have to be careful with the brand you choose, because not all water filters on the market are capable of removing these chemicals. Any activated carbon, ion exchange or reverse osmosis water filter should be effective at doing the job.
“These are the treatment technologies that are best for removing PFAS and related compounds from drinking water,” she says. “Activated carbon is already used in drinking water treatment and would be helping to remove PFAS compounds from treated drinking water in your location.”
Should we be drinking bottled water?
Switching to bottled water might seem like a simple solution, but unfortunately much of the available bottled water in supermarkets is processed from drinking water, and so may well contain exactly the same amounts of PFAS and related compounds.
“Non-treated bottle water sources, for example spring water, are subject to the same types of contamination as mains drinking water,” says Speight. “Bottled water can also be contaminated with microplastics, which pose their own health risks.”
If you are going to go for bottled water, opt for brands that treat their water before bottling it such as Aquafina and Nestlé Pure Life.
Another option if you are on the move, is to buy a filtered water bottle, again going for brands that have an activated carbon, ion exchange or reverse osmosis filter.
What should the Government do?
As well as investing more in testing technologies, which can detect a larger variety of PFAS compounds in our water, Speight feels that we need a more thorough picture of the extent to which our water is contaminated and how this varies on a daily or weekly basis.
“The recent mapping study that identified high levels of PFAS in our water, gave a picture of water contamination across the UK, but over a short period of time,” she says. “Nonetheless, it showed that these compounds have occurred in UK treated drinking water at some locations about the current 100ng/l threshold, and more locations are likely to have concentrations higher than the 4ng/l proposed limit. So the UK does need to urgently collect a detailed dataset across different seasons and source water conditions to more fully understand the situation and design appropriate treatment.”