All of the samples of infant formula tested by police after being suspected of possible tampering have tested negative for 1080.
The tests came after members of the public reported a number of infant formula tins that appeared to have pin-pricks in the seals.
Police collected the infant formula concerned and tests were carried out that showed the infant formula in those tins was safe.
Assistant Commissioner Mike Bush said the police were of the view that the problems with the seals arose from normal manufacturing or handling issues.
"The parents involved here did the right thing," he said.