You may be drinking bad tap water.
Not only that, you may also be boiling potatoes and brushing your teeth incorrectly.
Little-known government advice is urging us to change our tap water habits to reduce the risks of exposure to substances that could harm our health.
These include never using hot tap water for cooking, even if it is just to fill the boiling pot.
Here, MailOnline shares the guidance you probably had no idea about the Drinking Water Inspection (DWI)…
Government advice says Brits should avoid drinking or using hot tap water for cooking (file image)
Never drink from hot water or use it for cooking.
Compared to boiling the kettle, using water straight from the hot tap to cook or make a drink may seem like a simple time-saving trick.
But the DWI warns that people should only use the cold water faucet in the kitchen for both drinking and cooking.
This is because tap water carries a higher risk of being contaminated with metals such as copper and lead, which can have immediate and long-term health effects.
Although most homes no longer have lead pipes, DWI still recommends against consuming tap water, as the water may contain elevated levels of other metals.
It is not even recommended to use this type of water for cooking, such as filling a pot to boil potatoes faster, because boiling will not remove any possible traces of metal.
The DWI says: ‘Remember to only use cold kitchen water for drinking and cooking.
“It is not recommended to drink tap water because it may contain high levels of metals, such as copper, which makes the water taste astringent.”
Do you live in an old house? Leave the tap running until it cools before having a drink.
Exposure to lead in household water can harm mental development in children, as well as cause kidney and heart problems in adults.
Such is the concern that the use of this heavy metal in domestic pipes has been prohibited since the 1970s.
But the DWI warns that some homes in Britain could still contain metal and people should be aware of the potential risk.
Even modern homes are not necessarily safe, as unskilled plumbers or DIY home renovators may have used lead solder, the material used to connect two metal pipes, in the past.
DWI says the easiest way to check for lead pipes in your home is to find the shutoff valve.
If the pipe is a dull gray with a swollen joint next to the faucet and the metal turns a shiny silver when gently scratched with a coin, it and potentially others in the house are likely made of lead.
Once lead is found, DWI advises people to turn on the faucet they use for drinking and cooking before using it to clean out liquid that has been in the pipe for a long period of time and, as a result, has a higher lead content. .
The DWI says this is usually enough water to fill a dishwashing bowl or until there is a noticeable drop in water temperature that indicates it is “fresh” from the mains.
However, he stresses that this is only a temporary measure and that lead pipes or solder should be replaced as soon as possible.
Even brushing your teeth using the upstairs faucet may not be recommended, government officials advise (file image)
Avoid drinking and even brushing your teeth with water from overhead faucets if you have a storage tank on your roof.
Are you thirsty at night?
Please note that it may not be safe to fill a glass of water from the tap upstairs.
By the same logic, it could also be risky to brush your teeth using the bathroom faucet.
According to the DWI, many older properties get their water from above from storage tanks located on the roof or in the attic.
While modern, updated versions of these tanks are now considered safe to drink from, many older models have problems.
Some are too large, meaning the water in them can “sit” for too long and is technically not fresh enough to drink.
Other tanks are made of traditional metals that can rust over time, resulting in bits of metal in the water, albeit in small amounts.
Tanks must also follow a series of strict standards, such as having filters to keep out critters and not being located near a heat source that can cause the water to spoil more quickly.
The DWI says the easiest way to check if the overhead faucet is connected to a water storage tank is to turn the faucet all the way on and place your thumb under the spout.
If it can hold all the water this way, it is probably coming from a tank rather than the main.
What do the experts say?
Professor Alan Boobis, a toxicology expert at Imperial College London and a government adviser, said he does not personally follow DWI advice to avoid metals in tap water, but insisted it was sensible.
“Some substances are probably found in greater quantities in the water that is first drawn from the tap, for example if they leak from the pipes,” he said.
“There would be no harm in following this advice and it may well help to reduce the levels of some of the substances, although they are still likely to be below a level of concern.”
Professor James Coulson, a toxicology expert at Cardiff University, said that like many Britons, he was unaware of the government advice but followed his own precautions.
“Personally, I run the tap for about 30 seconds to make sure the ‘dead space’ has been cleared from the system and visually inspect and smell it before drinking,” he said.
“But that’s just my personal preference.”