A mother has called on a leading baby formula brand to recall a batch of one of their popular product lines after she opened a tin and discovered a dead lizard rotting inside.

Artilina Castanares, a 30-year-old mother-of-two from the outer north-western Sydney suburb The Ponds, said she made the unpleasant discovery on Friday when she opened a newly purchased tin of S-26 Original Process formula.

“I opened it and there was a funny smell. Its tail was sticking up and, thinking it was a thread, I lifted it up and it was a gecko,” Mrs Castanares said.

“I squealed and dropped it. I was in shock from then on,” she said.

Mrs Castanares said she immediately informed “Careline”, the product’s contact hotline listed on the side of the tin, about her discovery.

A spokesperson directed her to return the tin with the dead lizard inside to Aspen Australia, the company’s head office, for an investigation, but was advised she would have to wait up to two months before she heard anything.

“She [the spokesperson] was very casual about it. She said ‘send it in, and well send it overseas for investigation, but be aware it will take 6-8 weeks,’” Mrs Castanares said.

Mrs Castanares said this was an “unacceptable” response as “babies could be at risk.”

“I’m in shock,” she said.