The decision by Ravensdown and Ballance Agri-Nutrients to withdraw the nitrification inhibitor Dicyandiamide (DCD) from the market until acceptable residue levels have been internationally agreed is supported by Federated Farmers food safety spokesperson William Rolleston.
Trace residues of DCDs have been found in cow's milk. While there is no evidence to suggest the product is harmful to humans, there is no internationally agreed acceptable level.
This could put trade at risk if some countries decide to stop importing New Zealand milk because of it.
Dr Rolleston said the amount of DCD was so small that it was due only to the increased sophistication of testing technology that it was able to be found.
"This is the right move for dairying in New Zealand. It really shows the thoroughness of testing within New Zealand's primary industries and the high standard we put on ourselves to protect our reputation as a trusted supplier of food products," he said.
The DCD had been found only in liquid and powdered milk, not further processed dairy products, such as cheese and butter.
Dr Rolleston did not believe this would substantially damage the industry, as the product had been used only on about 500 farms, of about 12,000 in New Zealand.
"The important thing here is for New Zealand to maintain its reputation as a safe and reliable food-producing country which is transparent and upfront.
"The vast majority of New Zealand farms have not used DCD-based nitrification inhibitors, but we want our trading partners to know New Zealand's primary industries take this extremely seriously."
The last applications of DCD would have been in spring so it was unlikely any would still be detectable.
Dr Rolleston said DCD use had arisen after considerable pressure on farmers to find solutions for diffuse nitrogen, but it was more important that any solution be thoroughly scientifically tested in New Zealand conditions to ensure they were safe.
"The pause in DCD use reminds us that we need to ensure the regulatory system is up to date when we use and then test for new products," Dr Rolleston said.