BRUSSELS— A European Union scientific committee said Monday that it had evidence to show that a growth hormone used in U.S. cattle production is a "complete carcinogen" and warned that other hormones could cause a variety of health problems.
A second report by the committee alleged "abusive" use and inadequate control of six growth hormones in the United States.
The European Commission, the EU's executive body, was scheduled to review the reports later this week, and officials said the findings could lead to a total ban on U.S. beef imports and the risk of an escalating trade war.
The EU banned U.S. hormone-treated beef in 1989.
It continues to allow imports of about $20 million a year in beef products certified hormone-free. But the commission says recent studies showed that 12 percent of this meat also contained traces of hormone growth promoters, including chemicals banned in the United States.
The World Trade Organization has upheld a U.S. protest about the EU beef ban, ruling that while Europe had the right to protect the health of its citizens, it had not provided adequate scientific evidence for the ban. Last year, it gave the EU 15 months to implement the EU findings, a period that ends May 13.
But the commission says it needs more time to complete 17 scientific risk assessments, some of which are being carried out in the United States by American scientists. In the interim, it has proposed either allowing imports of U.S. beef provided it is labeled as containing hormone residues, or compensating the United States with trade concessions.
The labeling option appeared less likely Monday after the release of the two reports, which flatly rejected Washington's assertion that the hormones are safe. The independent scientific committee for veterinary measures relating to public health said there was substantial evidence to conclude that one hormone, 17beta-oestradiol, "has to be considered as a complete carcinogen."
"It exerts both tumor initiating and tumor promoting effects," it added. "In plain language, this means that even small additional doses of residues of this hormone in meat arising from its use as a growth promoter in cattle has an inherent risk of causing cancer."
However, the committee said it did not have sufficient data to establish a quantitative risk of this or the other hormones it is studying.
"Even exposure to small levels of residues in meat and meat products carries risks," the committee said, particularly for children below puberty. These could include endocrinal, developmental, immunological, genetic, neuro-biological and carcinogenic effects, the experts said.
The second report said that regulatory controls in the United States were "deficient" and in Canada "insufficient" in detecting hormone residues in meat products, in preventing the use of black market products or in enforcing the rule that hormone implants should be confined to an animal's ear.
"In the U.S.A. and Canada, repeated treatment of animals with hormones is common," the scientists said. "Unapproved hormonal substances are available on the black market. Neither the U.S. nor the Canadian meat inspection regulations provide for regular checks of animal carcasses for misplaced implants."
The scientists said U.S. inspectors do not even bother to check for the presence of some hormones in beef, including 17beta-oestradiol.
Both reports have been sent to the U.S. and Canadian governments for comment.
The United States has warned that it intends to impose punitive tariffs on up to $900 million worth of European exports unless the EU complies with the WTO ruling. It plans to announce a list of penalized products early next month.
The scientists expressed particular concern about the risks posed by misplaced hormone implants because they said this could lead to dangerously high concentrations, including "the possibility that the total content of an implant will be present in a portion of minced meat or in a batch of meat products."
They said a single implantation site could contaminate 4,000 glasses of baby food "so much that consuming even one glass would result in a dose to a baby of up to 33 times of what would be acceptable consumption for one day."
The vast bulk of U.S. beef is produced with hormones. The U.S. representative to the WTO, Rita Hayes, said last week that "over four decades of scientific research has found no justification for continuing the EU's ban.
"We are also," she added, "concerned by the lack of transparency of the EU's risk assessment studies."