It contained the preservative sodium benzoate, which on its own was acceptable, but was a cause for concern when mixed with three of the product's artificial colourings.
The fourth colouring was linked with cancer and other problems in laboratory animals; the fifth was banned in 12 countries; and the sixth was the subject of a petition to a US regulator for a ban on grounds of a link to cancer.
Tartrazine 102, sunset yellow 110 and carmoisine 122 - used in Zooper Doopers - are among six artificial colourings tested with sodium benzoate in a study of children at Britain's Southampton University.
The researchers concluded that consuming artificial colourings or sodium benzoate - or both - led to increased hyperactivity in children.
The European Food Safety Authority said the study provided "limited evidence" of a "small effect". However, it ordered a warning be placed on food and drink - except most alcoholic drinks - containing the colours. Britain's Food Standards Agency asked manufacturers to find alternatives.
The Wellington-based Safe Food Campaign's co-convener, Alison White, said New Zealand's food regulators had repeatedly ignored the studies she had cited that showed an effect on children.
Some British food manufacturers, whose products were also sold in New Zealand, had changed from artificial to natural colourings, she said. Food Standards Australia New Zealand spokeswoman Lydia Buchtmann said the colourings listed in Zooper Doopers were all approved as safe for general use.
Asked why the agency hadn't followed the British and European regulatory moves, she said the Southampton study was "very limited".
