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.

How does arsenic get into my water?

Arsenic dissolves into water as it passes rocks, ores or minerals containing it. It can be found in both ground and surface water sources.

What does arsenic do?

Non-cancer effects of arsenic can include:

  • Thickening and discoloration of the skin
  • Stomach pain
  • Nausea
  • Vomiting
  • Diarrhea
  • Numbness in hands and feet
  • Partial paralysis
  • Blindness

In addition to these, arsenic has been linked to several types of cancer, these include cancer of the bladder, lungs, skin, kidney, nasal passages, liver, and prostate.

How can I remove arsenic from my water?

While a number of technologies are avaialble workdwide, in New Zealand common ones are:

  • Oxidation/Coagulation/Filtration
  • Adsorptive medias
  • Reverse Osmosis
  • pre-filtration of other contaminants is also often needed