Oral health brand Colgate is coming under scrutiny after it was revealed one of its products contains triclosan, an antimicrobial agent banned by the US and potentially facing a review in New Zealand.
The agent, found in Colgate Total toothpaste, is often present in soaps, detergents and toys - but in September 2016, triclosan was outlawed by the US Food and Drug Administration (FDA).
In New Zealand, the approved use of triclosan in products was the subject of an application to the Environmental Protection Authority (EPA) for a re-assessment in 2016 - but that needed to be backed up with another request for change before a review took place, which has not yet happened.
The EPA said the person who made the follow-up request would also have to offer up some funds for more research to be undertaken.
But Cawthorn Institute environmental toxicologist Dr Louis Tremblay said it is clear that the triclosan in Colgate Total means it should not be marketed as a mass-consumer product.
"It has some advantages for gum disease if an individual has a problem, but isn't a toothpaste for everyone," he said.
"Chemicals play a beneficial role for the right reasons but can also have harmful consequences.
"Like any medication there are side effects. It's whether the benefits outweigh the side effects."
Consumer NZ researcher Jessica Wilson backed up Dr Tremblay's comments, telling NZME that Colgate Total should be avoided "if there are no good reasons for you to be using this every day".
Dr Tremblay said while he's not calling for a complete ban he believes "it's only a question of time before it's taken out of products" completely.
However Colgate have remained firm in their stance on their use of the chemical in the toothpaste.
"Colgate Total users can be fully confident in the safety of our toothpaste for daily use," a statement from the company read.
"It continues to be approved as safe and effective through a rigorous review by the US Food and Drug Administration and is approved by regulatory authorities in Europe, Australia, Canada, and New Zealand."
High-profile scientist Michelle Dickinson, better known by her pseudonym Nanogirl, says there is simply not "enough information available to assess the level of risk" posed by the chemical.
Most New Zealand manufacturers have already removed the chemical from their products as a result of 2016's triclosan ban by the FDA - with the exception of Colgate-Palmolive.
"Suppliers either advised that their products did not contain triclosan or any of the other ingredients listed by the FDA. Or if it was present, products were being reformulated by October 2017," said Foodstuffs NZ head of external relations Antoinette Laird.
"The only exception was Colgate Total, because of the benefits around the treatment of gingivitis.
"We haven't made a decision to remove products from our shelves, because of the proactive response from our suppliers."
Despite judgements in the US being passed down last year, the product has since returned to the public spotlight after a widely shared article erroneously claimed that Colgate Total was to face an imminent ban.