A government adviser in the UK has refused to put his name to a report which says the hormones used in cattle are safe for human consumption.
The report by the Veterinary Products Committee has been effectively discredited by John Verrall, a pharmaceutical chemist and consumer representative on the panel who says that humans are at increased risk of cancer from eating beef from cattle fed growth hormones.
Verrall says that over the last two years a number of important studies have shown that the information used by regulators to assess the safety of hormone residues in food has been wildly inaccurate.
He says it is clear that very much smaller amounts of sex hormones in food than previously thought can cause genital abnormalities in baby boys, premature puberty in girls and increase the risk of cancers later in life.
The European Union has banned the use of growth or sex hormones in cattle since 1982, and imports of such meat are prohibited.
But they are still used in Australia, New Zealand, the United States, Canada, Mexico and Chile.
Britain imports 4,700 tonnes a year of beef from Australia, but it is believed the hormones are used illegally in other countries.
The British government is being pressurised to introduce urgent testing of meat for the hormones by the green lobby group the Soil Association.
Richard Young, a policy adviser for the group, says almost 40 per cent of the beef commissioned in the UK is imported yet it is not subjected to the same level of residue testing as British beef.
The Veterinary Products Committee's report was completed in January and states that most of the evidence presently available suggests that the likely levels of human exposure to hormonally active substances in meat from treated animals would not be sufficient to induce any measurable physiological effect.
Mr Verrall however wants to produce a minority report stating his concerns and has threatened to resign over the issue.
He has heavily criticised the committee for ignoring research that suggests there is no safe minimum threshold of growth hormone residue in meat.
Danish Scientists at Copenhagen University support his view and say that even tiny amounts of hormones eaten by pre-pubescent children can be harmful in the long-term.
The Danish study however concerns a different hormone, oestradiol, and suggests its use could bring forward puberty in girls and raise the risk of genital abnormalities in boys.
Mr Verrall has been refused permission to publish his minority report which states that there is clear evidence of the risk to human health posed by growth hormones and there is no threshold dose-response for oestrogens.
Britain's Department for Environment, Food and Rural Affairs (DEFRA) has not as yet commented on but the issue which has coincided with a warning by the National Farmers' Union that a total ban on beef imports from Brazil should be imposed following the discovery by EU Food and Veterinary Officers that regulations on the use of drugs in cattle were lax and few residue checks in meat were being done.
The poor controls and the outbreak of foot-and-mouth in parts of Brazil have already prompted the United States and Australia to ban Brazilian beef.