Arsenic

Arsenic

Arsenic is a highly toxic element that naturally occurs in many minerals, its name is derived from the Greek work arsenikos meaning male, virile. During the bronze age arsenic was added to bronze to create arsenical bronze, an alloy with harder physical properties. Arsenic became a popular and widely available substance in the UK during the Victorian era where a preparation of arsenic, chalk and vinegar was eaten by women hoping to improve their complexion.

In 1858 more than 200 people were poisoned leading to 21 deaths in Bradford following the adulteration of the production of sweets with arsenic trioxide. The Bradford sweet poisoning case led to the introduction of the Pharmacy Act of 1858. As more become known about the toxicity of arsenic, compounds originally developed as pigments were repurposed as pesticides. In the 1930s a wood preservative called Tanalinth was developed from a mixture of chromate copper and arsenate. Concerns about the toxicity of Tanalinth have led to it being banned in the UK, EU and US.

Agency Limit (ppb)
UK - DEFRA 10
US - EPA 10
EU - EEA 10
WHO 10

Arsenic and our health

Exposure to high levels of arsenic causes acute poisoning with symptoms of vomiting, abdominal pain and severe diarrhoea but longer term, chronic exposure can lead to skin thickening/darkening, abdominal pain, diarrhoea, numbness and cancer.

Arsenic interferes with the biochemical pathways of the body and disrupts the energy systems leading to the death of cells. Chronic arsenic exposure can reduce potassium levels leading to increased risk of heart problems. Arsenic exposure from groundwater is a concern through pregnancy. Infants born to women exposed to higher concentrations of arsenic or for longer periods of time have higher mortality rates.

Long term exposure to arsenic in drinking water is known to increase the risk of bladder cancer and skin cancer. Further studies have proposed that arsenic can increase the risk of cancers of lungs, digestive tract, liver, kidney and lymphatic systems.

Arsenic in our drinking water

Arsenic occurs naturally in many minerals; the leaching of these minerals is a major source of groundwater pollution globally. The groundwater contamination of the Bengal Delta has caused serious arsenic poisoning to a number of people, a 2007 study found that 127 million people in more than 70 countries are probably affected by arsenic poisoning. The world health organisation has described the Bangladesh arsenic crisis as “the largest poisoning of a population in history” it is estimated to kill 43,000 people annually.

Arsenic contamination of groundwater is found in many countries including the UK. A study conducted by the British Geological Survey 2011/2013 looked at private water supplies in Cornwall and found that five percent of supplies had arsenic levels that exceeded the 10 ppm prescribed concentration or value (PCV).

Tests

Arsenic in your drinking water can be detected with the following tests.

Removing Arsenic

Arsenic can be reduced or removed from your drinking water using the following methods.

  • Reverse Osmosis
  • Anion Exchange Columns
  • Activated Carbon Filters

Further reading