Do we need to filter our tap water?

Drinking plenty of fluids is incredibly important for keeping body and mind working in optimum condition and we’re lucky enough to be living in a country that provides that on tap. However, do current treatment practices and the chemicals involved pose any significant health risks? Our drinking water’s journey from source to tap has come increasingly under scrutiny as of late with talk of hormones and contaminates leaving many people confused (including myself!). Is there anything to be worried about? We did some digging around and spoke to the experts to see if they could shed some light on some of the most talked about issues.

Is chlorine in our tap water a problem?

Chlorine is used as a disinfectant to rid our drinking water of waterborne microbes and maintain hygienic conditions in the pipes that transport it from treatment works to tap. However, concerns have been raised over the by-products produced from the process, which some research has linked to certain cancers. However, the DWI (Drinking Water Inspectorate) says that the amount of chlorine used is at such low levels by the time it gets to us that it doesn’t pose any harm (UK tap water has well below the 5mg/l standard set by the World Health Organisation). WHO also makes the point that any risks to health from chlorination by-products are extremely small in comparison with the risks associated with inadequate disinfection.

Freelance dietitian Priya Tew from Dietitian UK  opts to filter the chlorine out of her tap water purely to make it nicer to drink. “Personally, I like to drink filtered water due to the taste,” she tells us, and is of the view that filtering does not provide any additional health benefits. For her purposes, she has a filter fitted to her kitchen sink, but also recommends leaving a jug of water covered in the fridge overnight as a good way to remove the chlorine taste. She cautions against leaving it for longer than 24 hours though as without the chlorine, bacteria can start to grow. Carbon filters such as those from Brita can also be beneficial in this regard.

Is lead still an issue?

Lead carries some serious health risks especially for infants and children due to its effect on mental development. If your house was built before 1970, there’s a greater likelihood that your pipes could be made of it. This carries the danger that some may transfer to your drinking water as it flows through them. It’s worth noting though that if you live in a hard water area, that scale caused by it may help in reducing ‘wash off.’ If you’re unsure if you still have lead pipes, a few simple checks inside and your home can help ( here’s what to look for ) and if there’s doubt surrounding whether it’s in your water, you can also ask your water company to test it too.

Is the fluoride added to our tap water a good or bad thing?

For the most part it seems to be good (or at least not harmful). A small amount is found naturally in our tap water however some authorities add it in to help with tooth decay. The maximum amount that it can contain is 1.5mg/l and it varies from region to region ( here's a map  of fluoride levels in different areas). However, questions have been raised as to whether it does actually help with tooth decay and also whether its potential health risks (specifically in relation to the thyroid gland) outweigh its benefits. There are many opinions on the subject, but as nutritional therapist Amelia Freer  points out in a recent article she wrote on tap water , risks are “unlikely to occur with normal, everyday water consumption,” with a 2014 report from Public Health England stating that “water fluoridation is a safe and effective public health measure.” So with that in mind, I’m personally not too worried.

Is bottled water better?

No, not always. If you’re abroad and there’s a problem concerning the local tap water, then bottled water is certainly the safer option (to check the sanitation levels in the country you’re visiting, TravelHealthPro’s  recommended by the NHS). However closer to home, tap and filtered waters seem to be preferable. The reasons for this range from environmental impact to quality and packaging. “Bottled water often comes from a public water source or tap and is then treated, so it can be that you are paying to drink tap water that has just been filtered and put into a plastic bottle,” says Priya. Plus, with the planet already suffering from a surplus of plastic waste , using more just adds to the problem.

Some experts believe that BPA, a chemical used in some plastic bottles, can leach from the plastic into the liquid inside. “It’s an endocrine distributor and in this case mimics oestrogen to interfere with hormone balance,” says nutritional therapist Daniel O’Shaughnessy, The Naked Nutritionist . “BPA is also linked to reproductive health problems and cancers such as breast, ovarian and prostate.” Nutritional therapist Amelia Freer also advises her clients to try and avoid drinking water from plastic bottles with BPA too and opt for glass or stainless steel travel bottles instead.

Hormones and pesticides  - should we be worried?

There are concerns over the presence of oestrogens (from the birth control pill, which makes it way into sewage) and endocrine disrupting compounds (EDCs, from environmental waste) in our tap water, and their effect on our hormone levels. Are they in high enough quantities though to cause us harm? While there may well be small amounts in our rivers, the Drinking Water Inspectorate  (DWI) emphasises that they tend to only be found in immediate proximity to industrial and wastewater discharges and nearly all of them break down naturally due to their unstable nature. Studies funded by the European Commission have also demonstrated that current sewage and water treatment practices are highly effective at removing EDCs too so with all these factors in mind, it appears that the risk is minimal.

What about pesticides in our tap water?

A few raw water sources in England and Wales are at risk of contamination of traces of common pesticides, regarded by some experts as endocrine disrupters. However, the DWI doesn’t feel that at-home water treatment is necessary due to steps taken by water companies to remove them to below the strict European standards applied (0.1μg/l for each individual pesticide in drinking water). This is set not as a health based standard, but as a measure to generally limit the use of pesticides for environmental reasons. Practices include treating the water with activated carbon alone or in combination with ozone (to remove bacteria and microorganisms).

So if I do want to filter, which one should I choose?

There are a wide variety of different filters available ranging from jug filters to ones that can be connected to the water supply.

In addition to this, there are also various different filtering methods. These include carbon-activated, ceramic, ion exchange, mechanical, ozone and reverse osmosis. Carbon filters are probably the most well known and as mentioned earlier, can help with reducing the taste and smell of chlorine in your tap water. “Carbon filters bind contaminants and remove them from the water,” explains Daniel. “These include asbestos, chlorine, lead, mercury and volatile organic compounds (VOCs). However, carbon filters cannot remove arsenic, fluoride, nitrate or perchlorate.”

Daniel’s filtration method of choice is reverse osmosis. “This is probably the best one as it uses a semi-permeable membrane that can trap anything other than water - so you are just getting water. It can also remove fluoride too.” It can be on the expensive side though, with the DWI cautioning that the installation of RO treatment on a metered water supply can increase water bills by up to one third. This is because it produces a waste stream equivalent to 20-30% of the incoming flow. Consumers also need to give notice to their water company of their intention to install a RO system too. If this isn’t an economically viable option though, Daniel recommends a zero water jug such as the ZeroWater Ready Pour Water Filter Pitcher , £24.99.

The final word?

It’s still a little murky however, it seems overall that a filter isn’t essential for tap water from a health perspective due to the strict standards it has to adhere to. Regularly tested, carefully regulated and free, it’s more environmentally friendly than bottled water and when you consider how important it is to stay hydrated, its benefits outweigh its negatives. Out of all the chemicals potentially in it, lead seems to be the one that requires most immediate action (if your house was built before 1970 that is) however, the DWI provides some useful information on its website for assessing the risk.

Whether you still choose to filter your tap water seems to be more a case of personal preference and taste than safety worries (as seen with chlorine above). However, if you are concerned about your water supply or are just curious about it, the results of its testing history are published and available to every consumer on request. As for me though, these findings have gone some way to reassure me so if I do filter my water, it'll be more for flavour than to alleviate any health concerns for now.