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Lead is a neurotoxic heavy metal

Lead in drinking water samples five times legal limit, schools discover

Surprise lead discovery by schools project

School children recently made the shocking discovery that lead, a neurotoxic heavy metal, is present at up to five times the legal limit in water samples taken at 14 schools in the UK.

That probably wasn’t the intended outcome when 600 schools took part in the Great British Water Project run by the Don Hanson Charitable Foundation, which describes it as “a nationwide, interactive experiment… to study the quality of tap water across the UK”.

The maximum permitted limit is 10 micrograms per litre. But 14 of the schools taking part in the project found levels of up to 50 micrograms. The finding was confirmed by the Foundation itself, which no doubt was surprised.

“Lead is a dangerous metal which can cause serious poisoning if it builds up in the body.” (WaterSafe)

Read on to learn whether the tap water in your home or business may be contaminated by higher than permitted levels of this heavy metal, and find out what you can do about it.

Are there health implications?

Lead is a neurotoxin (a poison which acts on the nervous system). Since it was banned in products like paints and petrol, the majority of people in the UK are not at risk of poisoning. However, NHS Scotland warns that in most cases “it is small amounts consumed over time that build up in the body” and that:

“one of the main potential risks can be through drinking tap water if your property has lead pipes” (NHS Inform)

Even low levels in drinking water may be problematic. WaterSafe warns that “babies and young children are most at risk as their development can be affected”. And the Drinking Water Inspectorate (DWI) states: “the presence of lead… can have detrimental effects on heart and kidney function as well as mental acuity.” (DWI, 2020)

Is there lead in your drinking water?
How safe is your drinking water?

Lead contamination of drinking water probably higher than reported.

Whilst the DWI points out that “lead failures contribute a small proportion to the overall compliance risk index”, it acknowledges that “risks to public health from lead merit an ongoing conversation on the matter”.

Contamination by this particular heavy metal accounted for a small number of water company compliance failures in 2020. Faecal bacteria accounted for the highest proportion of failures. Of 10,551 tests conducted in 2020, 40 failed to meet the standard of 10 micrograms of lead per litre. To compare, iron accounted for 62 failures (from 46,849 tests) and nickel at 35 (from 10,534 tests).

However, it’s important to treat these figures with caution. The actual number of failures is likely to be greater than reported. Covid restrictions during 2020 saw a decrease in the number of test samples collected from domestic properties. More samples were collected from reservoirs and treatment works, which the DWI says are “of little value”:

“2020 figures for lead are not an indication of improvement in compliance with the lead standard but an indication of the impact of the pandemic on sampling.” (DWI)

Lead pipes and fittings in older properties should be replaced
Pipes and fittings in older properties should be inspected.

Why is lead in UK tap water? How many homes might be affected?

Lead pipes and solder were banned from UK water infrastructure decades ago. So, it’s properties built before 1970 which are most likely have lead pipes and solder which have not yet been replaced. These could be inside the property itself (which the owner is responsible for), or in the service and communication pipes serving the property.

“Even in properties with no lead pipework there may be other sources of lead in drinking water, such as brass fittings or improperly used lead-based solders.” (Watersafe)

Brass fittings contain small amounts of lead which corrode if water is left standing in them, or if the water is acidic (soft). Keep reading for more information on higher risks at properties in soft water areas.

An estimated 8 million older properties in the UK still have lead drinking water pipes or fittings (Speight). Residential and business properties are affected, as well as schools. ‘Excess’ levels have also been found in drinking water supplies to care homes and churches. And lead pipes have even been found on the premises of water utility companies themselves, which the DWI considers “disappointing”.

How can we protect ourselves from heavy metals in tap water?

1. Inspect your property and replace old pipes and fittings.

This is especially important if you have young children at home. Homeowners and businesses are responsible for the plumbing within their property boundary. So it’s worth checking your pipes and fittings (unpainted lead pipes are grey). Any lead pipes or fittings will need replacing with copper or plastic pipes, with non-lead solder on fittings and joins.

Whilst it’s illegal to use lead solder on pipes supplying drinking and washing water, it is not banned outright. It can still be used on heating systems. Use a trustworthy, approved plumber who will not knowingly or unknowingly use unsafe solder on your water supply pipes. WaterSafe can help you find an approved plumber.

NHS Inform advises that children and adults with symptoms of poisoning, who live in properties with lead pipes, should contact their GP.

2. Install a drinking water purifier.

Even if you don’t have old pipes in your property, lead in your drinking water might still be a problem. This is especially likely if you live in a soft water area.

Soft water areas are at particular risk of contamination because soft water is acidic and dissolves pipes. Soft water is common in south and west Wales, Northern Ireland and Scotland. In England, soft water areas include Devon and Cornwall and Yorkshire.

Water companies add orthophosphate to our drinking water supply to mitigate the impact of lead. Orthophosphate is a corrosion inhibitor; it binds to metal surfaces and so should prevent leaching from pipes. However, as the Hanson schools initiative and the DWI 2020 report show, clearly this is no failsafe.

So the best thing you can do, after checking your property for old pipes and fittings, is install a water purifier.

PurityPRO water purifiers protect against lead in drinking water
A PurityPRO water purifier installed with Quatreau Touch tap.

Water purifiers protect against contaminants in UK tap water.

PureH2O’s technologically advanced reverse osmosis water purification systems remove 99.99% of all organic contaminants and impurities and 98% of all inorganics. This means you will be protected from lead, as well as other heavy metals such as copper, which is associated with Alzheimer’s disease.

With a PureH2O purifier, you’ll also be protected from all natural impurities, as well as man-made contaminants. These include toxic ‘forever chemicals’ PFASs, chlorine by-products associated with bladder cancer, pesticides and fertilisers, microplastics, hormone and drug residues to name but a few.

Our water purifiers are compact and fit in a standard 600mm cupboard. They are energy and water efficient and easy to maintain, requiring servicing just once a year. They provide peace of mind and help you take control of what goes into your body.

Pure water is delicious and safe for the whole family to drink. It’s far purer than any filtered or bottled brand – it’s drinking water as nature intended. Our purifiers are for everyone, but you might find it reassuring to know that they’re used by some of the UK’s leading food and drink businesses, including Raymond Blanc at Belmond Le Manoir aux Quat’ Saisons and Planet Organic stores.

“The unique characteristics of PureH2O make it an essential ingredient in the diet of health conscious individuals. It’s the thinking person’s water.” – Renee Elliott, Founder / Managing Director, Planet Organic

How to order a water purifier for your home or business.

We have a range of purifiers to suit your drinking water requirements. We supply our systems to homes, offices, restaurants and hotels and back up your installation with an annual service by trained engineers. Call us on 01483 617000 email or fill out our contact form.


The Drinking Water Inspectorate covers England and Wales; Scotland and Northern Ireland are served by The Drinking Water Quality Regulator.


Drinking Water Inspectorate ‘Drinking Water 2020’, Crown Copyright 2021: accessed 27.10.21

NHS Inform ‘Lead Poisoning’ accessed 28.10.21

Speight, V ‘What Contaminants Lurk in the UK’s Drinking Water? An Expert Explains’ The Conversation, 14.09.21 accessed 26.10.21

Tapper, J ‘Science project reveals high lead levels in schools’ water’ The Observer, 05.09.21 accessed 25.10.21

WaterSafe ‘Lead in Water’ accessed 27.10.21


Don Hanson Charitable Foundation Schools Programme ‘The Great British Water Project’ accessed 25.10.21


PureH2O Ltd manufactures, installs and maintains the world’s most innovative water purification systems and the most technologically advanced boiling, chilled and sparkling water taps. Since 1991 we have been committed to providing our domestic and commercial customers with the purest, safest, most sustainable choice of drinking water, which helps them reduce their environmental impact by avoiding single-use plastic bottled water.

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