Health Canada says it won't approve the controversial bovine growth hormone (rBST) that allows cows to produce more milk.

The department made the decision after receiving a report that concluded that the hormone would be too dangerous for cows.

It made the decision after reviewing one of two reports it commissioned. A committee of veterinarians concluded that the hormone, which is regularly injected into the cow, causes an udder infection called mastitis, infertility and an increased risk of lameness.

The problems could be so severe that farmers risked having to destroy up to a quarter of their herds.

Joel Weiner is a Health Canada spokesperson. He says the decision was made on sound research. "In this case we've had the benefit of scientific advice from outside experts and that has helped us resolve a difference of opinion internally."

That difference of opinion was at the heart of the controversy surrounding the bovine growth hormone.

Some scientists in the department's bureau of veterinary drugs warned that the product was dangerous. But they complained about bosses who forced them to water down their findings.

Now a committee appointed by Health Canada has reached some of the same conclusions.

Blair Stannard speaks for the Professional Institute of the Public Service. It represents the scientists. "Their concerns centred upon the fact that sufficient attention had not been paid to the safety of the product. And there were concerns, certainly on the animal side and it appeared that Health Canada was trying to have that suppressed somehow."

But this isn't the end of the story. Liberal Senator Eugene Whelan for one is concerned about the pressure scientists say they're under. Last year, they talked about that pressure during testimony before Whelan's committee. It's preparing an interim report on the growth hormone that's supposed to be published sometime next month. Whelan says his committee isn't finished examining the BST controversy. "I'm still not happy about all these things that have taken place and I think we should still continue our investigation and hear more evidence from the scientists before we close the door on this issue," he said.

Health Canada says its decision proves that it's not the secretive organization critics say it is. But while those same critics welcome the decision on the bovine growth hormone, they're still angry over the way it was reviewed.