Access to clean drinking water is essential for good health.  Unfortunately, for many people living in developing countries, finding safe drinking water is a difficult task as water is often contaminated with natural or synthetic pollutants including bacteria, salts, pesticides and heavy metals.

Most people living in the United Kingdom assume that their water is safe and free from these kinds of contaminants.  However, that is not always the case!  Some municipal water systems in developed countries contain a number of contaminants that may affect your health. Below we explore the kinds of contaminants that could be lurking in your water and explain what you can do to avoid consuming them.

Types of Contaminants

It is very rare for water (H2O) to be completely pure.  This is because water can absorb other kinds of substances very easily.  Even rainwater contains atmospheric contaminants including carbonic acid and small amounts of salt. 

Most municipal water supplies in the United Kingdom are using very old pipes that are full of contaminants that can be absorbed by water; a serious problem for people who are concerned about their health.  The types of contaminants that water can hold fall into four categories:

   Physical contaminants
Dirt, rocks, sediment and other organic matter.

   Biological contaminants
These are microscopic organisms found in the water.  They include bacteria, parasites, protozoan and viruses.

   Chemical contaminants
These include manmade or natural chemical contaminants like mineral salts, nitrogen, drugs, pesticides and heavy metals.  In the UK, some chemicals are added to municipal water in an effort to make it safer.

   Radiological contaminants
These are chemical substances that have radioactive properties.  They include plutonium and uranium.

The Most Common Contaminants Found in UK Water

The most common contaminants found in drinking water in the UK include:


The United Kingdom has been adding a chemical called chlorine to its water supply for more than 100-years.  It is added in an effort to kill any bacteria that may be residing in the water.

While that sounds like a good idea, there is some evidence that indicates drinking chlorine may cause health problems.  For example, a 2014 research paper found that chlorine might be linked to the development of food allergies. Some forms of bacteria are also immune to chlorine, such as cryptosporidium; the cause of dysentery.


Some water utility companies in the United Kingdom perform artificial fluoridation of water.  This is done in an effort to improve the dental health of consumers.  However, there are some concerns about the negative health impacts that occur after consuming this chemical.

There are a wide variety of microorganisms found in tap water.  Most of these tiny life forms are not harmful to human beings and can be consumed safely.  Chlorine can also be used to kill most of the microorganisms present in water. 

There are a few notable exceptions to this, including the bacteria M. Avium paratuberculosis (MAP). This passes from farm animals into the water supply.  MAP is a very hardy microorganism that can survive chlorination.  Some scientists suspect it may contribute to causing Crohn’s disease, a debilitating health condition.

Cryptosporidium is another common microorganism found in water.  It is also resistant to chlorine and can cause gastrointestinal illness.

There have been a number of studies highlighting the danger of pesticides entering the water supply.  Scientists suspect that some of these chemicals may be linked to a decline in human fertility.  Thankfully, carbon filters are reasonably effective at removing pesticides from drinking water.

Chemicals From Plastic
Water can cause many types of plastics to disintegrate over time, resulting in some nasty chemicals leaching into the water supply.  Scientists have already discovered that some substances released from plastics into water can cause cancer.

Trihalomethanes are chemicals that occur because of interactions between chlorine and certain forms of organic matter found in water.  They have been associated with negative health effects including cancer and changes in the reproductive system.

Heavy Metals & Radioactive Substances

The human body requires some metals for maintaining good health, like magnesium and selenium.  However, some heavy metals can be detrimental to your health including arsenic, radium, aluminum, copper, mercury, cadmium, barium and lead.  Trace elements of these metals are often found in municipal drinking water. 

What Can You Do To Avoid These Water Contaminants?

To avoid the possible health concerns associated with these contaminants, it is important to purify your water.  The most common water purification techniques include:

   Water purification tablets
These tablets will kill bacteria and other microorganisms in water that cause health problems.  They are a great option for camping or traveling.

   Boiling water
Boiling your water is perhaps the easiest way to kill microorganisms.  However, boiling will not remove heavy metals, salts and most chemicals.

   Using chemicals
A variety of chemicals can be used to kill biological contaminants in water, including chlorine, iodine, hydrogen peroxide, silver, organic acids and alkaline agents.

Water filtration can remove many of the contaminants that municipal water contains.  Filtration can be performed using a wide range of materials including sand, diatomaceous earth, carbon filters and porous stone.  Carbon filtration is the most common form of water purification and is used in most water filters.

   Reverse osmosis machines
Reverse osmosis uses pressure to push water through a membrane and remove impurities.  Whilst technically it is a filter, reverse osmosis can produce very pure water that is free of heavy metals, bacteria and physical contaminants.

Perhaps the most effective form of water purification, which involves the water being boiled then condensed and collected.  This is one of the few methods that can produce 100% pure water.