Fonterra is reassuring the public and New Zealand's trading partners that the chemical dcd found in some of its milk products poses no risk to human health.
Dcd is applied to pastures to prevent fertiliser by-products from leaching into waterways.
Fonterra announced the dcd discovery on Friday and is rejecting claims that it delayed making the chemical's presence public.
And while it admits the scare has created concerns internationally, chief executive Theo Spierings said "safety is part of our DNA".
Spierings said Fonterra received the first test results in September 2012 and the Ministry of Primary Industries (MPI) assured them it was not a food safety issue.
"We have been closely involved in a working group with MPI, the fertiliser companies, scientists and other dairy industry representatives gathering information, scientific opinion, and undertaking further tests," Spierings said.
Fonterra stressed that there is no risk to human health.
"The minute traces of DCD detected were around 100 times lower than acceptable levels under European food safety limits. If there had been a food safety issue, we would have been the first to speak out," said Spierings.
DCD has been removed from the market and Fonterra said it can back up assurances about the safety of its products with "strong science".