Is there Arsenic in our Groundwater and Aquifers?

There has been much research done on arsenic occurrence and behaviour in the environment over the past decade or so, and environmental arsenic problems have been found in various countries across the globe.

Arsenic can naturally be mobilised in water and the ground via microbiological activity and weather reactions. Anthropogenic activities such as groundwater abstraction and metal mining can also initiate or exacerbate mobilisation.

Is there Arsenic in our Groundwater and Aquifers?

Drinking water constitutes a major pathway of arsenic to humans, and although concentrations of arsenic in drinking water are usually lower than the provisional guideline values set by the World Health Organisation (WHO), they can sometimes be far in excess of the statutory drinking-water limits, posing a potentially severe health threat.

Groundwater is generally more vulnerable to arsenic contamination than surface water is. This is due to the interaction of groundwater with aquifer minerals and the increased potential in aquifers for the existence of physicochemical conditions that serve as favourable conditions for the release of arsenic.

Most of the world’s recognised arsenic-related health problems are linked to long-term use of groundwater for drinking. The worst cases have been linked to aquifers in Argentina and Mexico and parts of Bangladesh, China, India, and Nepal.

In the UK, as survey conducted on a private water supply in Cornwall, commissioned by the UK Health Protection Agency, showed that 5% of the drinking water samples taken exceeded the As limits set down by WHO.

According to the UK-based anti-fluoridation group, the National Pure Water Association, fluoridation increases arsenic levels in drinking water (NPWA Press release July 2000). In the UK, the amount of arsenic in most tap water is miniscule, but some private wells are not monitored or tested for arsenic, which could pose a problem.

“Arsenic can replace phosphorus in the DNA structure, resulting in conformational changes and strand breakage. All inorganic compounds of arsenic are toxic, in particular arsine gas, AsH3. It is extremely toxic to humans, with headaches, vomiting and abdominal pains occurring within a few hours of exposure.”