The Food and Drug Administration said yesterday it will test raw milk weekly around the nation to determine whether it contains certain antibiotics.

The agency said 250 locations across the country will be chosen for testing and raw milk samples will be collected each week from five of these sites, selected randomly.

The samples will be tested for the presence of eight sulfa drugs and three forms of tetracycline. The FDA said that when residues are found, the states will be told and the agency will help track down the source.

Antibiotics are often used by veterinarians to treat infections in dairy cattle. Much of the nation's milk supply is already tested for penicillin and related antibiotics.

"As newer analytical methods become available, milk will be monitored for additional drugs," the FDA said in a statement. "The system will add another layer of protection for consumers."

Rep. Ted Weiss (D-N.Y.) attacked the plan as inadequate.

"Testing five milk samples per week means that each processing location in FDA's program will be visited only once a year," he said in a statement. "FDA's attempt to describe this as a nationwide program is ludicrous. To even call it a modest proposal is a wild exaggeration."

Weiss, who is chairman of the House Government Operations subcommittee on human resources, conducted hearings earlier this year on the FDA's milk-testing methods.

He said more hearings may be needed "to examine whether the agency purposely designed a plan that would not find any residues. FDA's paltry effort will tell the public virtually nothing about the true extent of animal drug residues in milk."

In November, Weiss released a General Accounting Office study that recommended the FDA work with dairy states to improve screening tests for drug residues in milk. The GAO study said the agency should also test, on a random basis, the types and amounts of drugs found in state screening samples.