In an open letter to Health Minister Nicola Roxon, the 15 scientists also called for all genetically modified food to be labelled.

The call comes as state and federal health ministers prepare to convene at a Food Regulation Ministerial Council meeting in Adelaide tomorrow.

A spokeswoman for the parliamentary secretary for health and ageing, Senator Jan McLucas, said the processes for assessing and labelling any food in Australia were based on world's best practice.

Because genetically modified foods were comparatively new, Food Standards Australia New Zealand adopted ''a very cautious approach to ensure first and foremost that they were safe to eat''.

Adelaide's Institute of Health and Environmental Research director Judy Carman said the food standards body was not responding to the needs of consumers.

''Genetically modified food is fed to everyone,'' Dr Carman said.

''You need to have long-term animal studies so you can work out what the risks of cancers are and various health problems that take years to develop.

''These safety assessments need to be comprehensive and they need to be done by people who are not associated with the genetically modified crop.''

The Institute of Health and Environmental Research is a not-for-profit institute with a scientific interest in the safety of genetically modified organisms.

A Health Department spokes-woman said Food Standards Australia New Zealand assessed all genetically modified foods for safety on a case-by-case basis. The body only approved those found to be safe for human health and the environment.

The open letter is a Greenpeace initiative and includes two Australian signatories, including Dr Carman.

It states, ''In recent years, it has been found that the effects of genetically engineering our food are more complex and unpredictable than we could ever have predicted.

''Governments and regulatory agencies worldwide have displayed growing caution in response to this new understanding.

''In Australia, meanwhile, our food regulator ... is one of only a few regulators in the world to have approved every single application it has received for [genetically modified] food products.''

A spokeswoman for the standards body could not confirm whether this was correct.

Foods containing genetically modified ingredients, additives or processing aids must be labelled with the words ''genetically modified'' where there is novel DNA and/or protein in the final food, or the food has altered characteristics. An altered characteristic means it is significantly different from its non-genetically modified counterpart.

The standards code allows a food to contain up to 10g/kg (1 per cent) unintended novel DNA and/or protein per ingredient without being labelled. Vegetable oils that generally contain no plant proteins do not require labelling.

It is the states' and territories' responsibility to monitor compliance with labelling regulations.

The letter calls for comprehensive labelling of all genetically modified food, including highly processed products such as oil, starches and sugars. It also includes meat, milk, cheese and eggs from animals fed genetically modified feed.