The sachet infant formula had been destroyed and the tinned formula had been placed in the customer service area, which could only be accessed by staff, Mr Ward said.
"We've moved it out of the public area and into a secure area where it can't be tampered with."
He had complete confidence the tinned products was safe, he said.
"If anybody tampered with a can it would be immediately obvious."
Trust House chief executive Alan Pollard said Featherston Supervalue had been proactive in its response.
"All of the infant formula has been taken off the shelves and located in a secure area behind the counter where customers have to ask for it."
Owner operator of Masterton Pak'nSave Paul de Lara-Bell said the store had checked all its tinned infant formula and moved it to the customer service area.
"It's under constant watch by staff and also by CCTV as well."
Sachet formula was off the shelves.
In an email sent to customers, Pak'nSave advised it was limiting formula purchases to two tins per customer per product.
A spokesman for Masterton New World said the store had checked all its tinned infant formula on Tuesday and it was still available on the shelves.
"It's being monitored and we've got posters up explaining what's going on."
CCTV cameras and staff were monitoring the formula, he said.
Sachet formula had been removed from sale.
Foodstuffs, which owns New World and Pak'nSave, said customers would be subject to heightened surveillance, with higher security in-store.
The company said that where possible there would be continuous CCTV monitoring of the shelf.
A Masterton Countdown spokesman said the store's tinned infant formula had been checked before being removed from the shelves and placed at the service desk.
Sachet infant formula was off shelves until further notice.
Other retailers had also tightened security around infant formula.
In an email to customers yesterday, The Warehouse said it had increased security around infant formula, relocating it to the customer service counter and withdrawing it from sale online.
Meanwhile Plunket's chief operating officer Andrea McLeod said Plunket had received a "steady" level of calls on Tuesday night from concerned parents.
"Our nurses gave advice to concerned parents and caregivers based on the information from MPI. The risk of contamination of baby formula is very low and to reduce risks even further, check all packaging carefully. Look for tears, rips, holes, significant bulging or other signs of tampering, and check the entire can/package including bottom and sides."
She advised anyone who was concerned to contact PlunketLine or HealthLine for advice.
Wairarapa police said no incidents relating to infant formula had been reported.
Senior Sergeant Mike Sutton said officers had been advised on the process to follow for safe handling of the poison, which included wearing gloves and masks.
"We have been updated and briefed on what to do if anything is reported."
