Is there lead in UK tap water?

Most UK tap water contains trace amounts of lead, typically below 1-2 parts per billion (ppb). The lead comes not from the water supply itself but from old lead pipes and solder in the plumbing between the water main and your tap. Homes built before 1970 are most likely to have lead pipes.

What is the legal limit for lead in drinking water?

The UK legal limit for lead in drinking water is 10 micrograms per litre (10 ppb), set by the Drinking Water Inspectorate under the Water Supply Regulations 2016. The World Health Organisation also recommends a maximum of 10 ppb. There is no known safe level of lead exposure.

How do I know if I have lead pipes?

Check the pipe where it enters your property (usually under the kitchen sink or in the cellar). Lead pipes are dull grey, soft enough to scratch with a coin, and slightly bulge at joints. If your home was built before 1970, there is a good chance some lead pipework remains. Your water company can also tell you if the mains connection to your property is lead.

How can I reduce lead in my tap water?

The most effective solution is to replace lead pipes with copper or plastic. In the short term, run the tap for 30 seconds to 2 minutes before drinking (especially first thing in the morning) to flush standing water from lead pipes. A point-of-use water filter certified for lead removal (NSF/ANSI Standard 53) also works well.

Lead in Tap Water UK: Risks, Limits & How to Check

What is Lead in Tap Water?

Lead is a toxic heavy metal that can dissolve into drinking water as it passes through old lead pipes, fittings, and solder. Unlike most water quality parameters, lead contamination happens after the water leaves the treatment works — in the pipework between the water main and your tap.

In the UK, lead pipes were commonly used for domestic plumbing until the 1970s. While water companies have replaced many lead mains pipes, the section from the boundary of your property to your kitchen tap (known as the supply pipe) is your responsibility, and many remain in place.

UK Legal Limits

The UK Drinking Water Inspectorate (DWI) sets the legal limit at 10 micrograms per litre (10 ppb). This matches the World Health Organisation guideline. However, many health researchers argue there is no safe level of lead exposure, particularly for children and pregnant women.

For context, typical UK tap water contains between 0.5 and 5 ppb of lead. Homes with lead pipes may see levels of 10-50 ppb or higher, especially from water that has stood in the pipes overnight.

Health Effects of Lead

Lead is a cumulative toxin that builds up in the body over time. Even low levels of exposure can cause harm:

Children: Impaired brain development, reduced IQ, behavioural problems, and learning difficulties. Children absorb lead more readily than adults.
Pregnant women: Lead crosses the placenta and can affect fetal development. It is also associated with increased risk of miscarriage and premature birth.
Adults: Long-term exposure is linked to high blood pressure, kidney damage, and reduced fertility.

How Lead Gets Into Your Water

UK water treatment works add phosphate dosing to create a protective coating inside lead pipes, which significantly reduces lead dissolving into the water. However, this coating can be disrupted by plumbing work, changes in water chemistry, or periods where water sits still in pipes (overnight or during holidays).

How to Reduce Lead in Your Water

Replace lead pipes: The only permanent solution. Costs typically range from £500-2,000 for the internal supply pipe. Many water companies offer grants or free replacement schemes — contact yours to check.

Run the tap before drinking: If you have lead pipes, run the cold tap for 30 seconds to 2 minutes before using water for drinking or cooking. This flushes the standing water that has been in contact with lead.

Use a water filter: Jug filters with activated carbon or reverse osmosis systems can reduce lead. Look for filters certified to NSF/ANSI Standard 53 for lead removal.

Never use hot water for cooking: Hot water dissolves more lead from pipes. Always start with cold water and heat it on the stove or in the kettle.

Check Your Water's Lead Level

Enter your postcode on WaterGrade to see the measured lead level for your water supply zone. Remember that your individual reading may differ if you have lead pipes in your property.