Dr Peter Trolove from the Federation of Freshwater Anglers operates spectrometer testing machine at a water testing event.

Staff and volunteers from Greenpeace Aotearoa offered free water testing for nitrate in communities in Canterbury, Aotearoa New Zealand.

These communities have high levels of intensive dairying. The overuse of synthetic nitrogen fertiliser and the urine from dairy cows causes nitrate contamination in drinking water supplies.

Nitrate contamination has been linked to adverse health effects, from bowel cancer to premature births.