What is Arsenic?
Arsenic is a metalloid element which occurs in the earth’s crust. It is common in geothermal areas and in conjunction with sulphur and metals.
In New Zealand it has been commonly found around, Rotorua, Taupo and Hanmer Springs
In its inorganic form, arsenic is highly toxic to humans.
One of the topics of debate is whether arsenic should be removed from the whole supply, or whether point of use is sufficient. This is because arsenic can also be absorbed through the skin. So while most exposure is from ingestion, not enough is known for a definitive answer. However the cautious approach is recommended
New Zealand Drinking Water Standards give a maximum allowable value of 0.01mg/L.