Arsenic in Cornwall: Water Contamination Study

24 November 2014

In places like Bangladesh and China there is a major and gravely serious issue with arsenic in water supply. The concentrations of arsenic found in some water supplies is leading to widespread arsenic poisoning and severe health implications. Alarmingly, one in five deaths in Bangladesh are due to arsenic poisoning. Globally, it is estimated that 200 million people are unknowingly exposed to unsafe levels of arsenic in their drinking water.

Arsenic is a chemical element that is present in many minerals found widely in the earth’s crust. It exists in elevated concentrations in some groundwaters due to the local geology. Arsenic can be introduced into water through the dissolution of these minerals. The presence of arsenic in your water supply poses a significant health risk, especially in concentrations above the WHO recommended 10 micrograms per litre of water (µg/l). Arsenic is a known carcinogen with the International Agency for Research on Cancer (IARC) concluding that inorganic arsenic (the form most commonly found in water) can cause cancer of the lung, skin and bladder. Professor Ramon Vilar from the Department of Chemistry at Imperial College London states: “Having a high level of arsenic in drinking water is a serious problem in many countries, putting people’s health at risk.” A number of the effects of drinking arsenic-contaminated water do not show up for a number of years.

Thankfully, arsenic poisoning from contaminated water is very rare in the UK. Having said that, arsenic is found in tap water in untested private wells across Cornwall and parts of Devon and it is these that present the highest risk. Long-term exposure to smaller concentrations of arsenic can be harmful.

arsenic in cornwall

Image: Levant Mine and Botallack Mines, Cornwall


Arsenic in Cornish Water

How is Arsenic getting into Cornish drinking water?

Cornwall is rich in minerals and its unique geology means that it is a county known for high environmental arsenic. During the Nineteenth Century, Cornwall dominated the arsenic industry so much so that by the 1870s a small number of mines in Cornwall produced over half the world’s arsenic. With arsenic widely distributed in the rocks, soil, and air, it is not surprising to still find it at low levels in some private drinking water supplies.

If you combine Cornwall’s mining history and geology with the fact that there are more than 3500 private water supplies then you can say how potential issues with arsenic contamination can arise. With numerous properties taking their water supply from boreholes, wells or streams, an estimated 9000 people use a private water supply (according to a 2013 report by the Drinking Water Inspectorate). Concentrations of arsenate, the chemical form of arsenic in water, are found where water is sourced from private wells. If you water is not provided by South West Water then there is a chance it could be contaminated with arsenate and other contaminants that you may not notice from the taste or smell.

For more information on arsenic read our Arsenic in Water Supply blog.


geevor arsenic mine cornwall

Image via Geevor Mine, Cornwall



The Effects of Arsenic in Cornish Water Study

The following is an overview into scientific studies into the amount of arsenic in some Cornish water. To read more into the study click here.


Who: The British Geological Survey commissioned by the UK Health Protection Agency (now part of Public Health England).


When: March 2011 – March 2013


Why: More research was needed into groundwater in Cornwall and the potential exposure to the carcinogen arsenic and its impact on human health.


How: Sampling campaign of 512 properties in Cornwall served by private water supplies.


Findings: 5 per cent of drinking water samples collected exceeded the 10 µg/L prescribed concentration or value (PCV) for arsenic.


What’s Next: A further study will look at exposure and determine how much arsenic is being taken up by the Cornish population. It will use toenails, urine and hair to appraise this.


Nanven beach Cornwall

Image: Stream. Porth Nanven beach Cornwall


Removing Arsenic from Water

If you have a private well in Cornwall, it is vitally important to get the water you use tested for arsenic. In lower concentrations, arsenic is particularly difficult to measure accurately. You can pay the Cornish Council and other organisations to take a sample of your water and analyse it. Be aware that seasonal variation, particularly between wet or dry months, can have an affect on any tests carried out. Samples are normally taken from a kitchen tap or one that you use regularly for cooking and drinking.

In other parts of the world digging deeper wells and purification are the methods employed to remove arsenic from water. Advances in purification techniques mean that it is possible to remove all trace of arsenic from your water supply. Aquatec – the Pure Water People are able to remove arsenic from your water supply with our whole house water purification systems. At Aquatec – the Pure Water People we have designed purification systems that ensure that when you pour a glass of water it is as clean as it can possibly be. We believe that all contaminants especially harmful heavy metals should be banished from your drinking water and that arsenic-free drinking water should be expected.