KEY POINTS:
The Ministry of Health has updated a list of toothpastes containing the toxic chemical diethylene glycol - also found in antifreeze.
A ministry spokesperson said many of the Chinese-made brands had been brought into the country illegally and were still being tracked down.
The Institute of Environmental Science tested 52 toothpaste products believed to have been manufactured in China and found 16 with unacceptable levels of diethylene glycol.
The amount varied from less than 3 per cent to more than 11 per cent, although the ministry said any amount of toxic chemical was obviously to be avoided.
While the ministry stopped short of telling people to avoid all Chinese-made toothpaste, it said that while people should check the ingredients, diethylene glycol may be present even when not listed on the label.
The chemical can harm some people, particularly young children and those with liver or kidney disease.
Symptoms associated with minor exposure include nausea, vomiting and headache.
Severe exposure can cause liver, blood and kidney disorders, seizure and coma.
The ministry said none of the amounts found in toothpastes would fall into the severe category.
Anyone using one of the unsafe toothpastes should stop immediately and seek medical advice if they have felt unwell.
The ministry said there was no reliable information about how many people might be using them.
Products identified as containing diethylene glycol in New Zealand are:
Excel 120g
Maxam 120g
Evafresh 90g
Tian Qi in green/yellow pack 105g
Hei Mei Cpp 160g
Hei Mei Cpp 105g
Hei Mei with green/yellow pack 160g
Hei Mei with green/yellow pack 105g (2 samples)
Hei Mei in yellow pack with monkey detail 42g
Hei Mei in green pack 160g
Mr Cool 120g
Mr Fresh 120g
Dr Cool 120g
Smile 2 120g
Crescent 181g
Tri Leaf Spearmint 145g.
- NZPA