WASHINGTON (Reuters) - The U.S. Food and Drug Administration lacks access to food safety tests that could have helped identify problems at a peanut plant at the center of one of the biggest food recalls in U.S. history, members of Congress said on Thursday.

The salmonella outbreak traced to a Peanut Corp. of America plant in Blakely, Georgia, has sickened more than 550 people, more than half of them children, and may be linked to eight deaths.

“We would like to have more information. There is no question,” Stephen Sundlof, director of the FDA’s Center for Food Safety and Applied Nutrition, told a hearing of the Senate Agriculture Committee.

Under law, a company does not have to notify the agency if it discovers salmonella or other contamination. The only time FDA can require information from a plant is if tainted product was shipped from it.

In the case of Peanut Corp. of America, the FDA says the plant found 12 instances of salmonella since 2007, only to retest the product to obtain a negative result before illegally shipping the products for sale.

The FDA and the Justice Department are conducting a criminal investigation of the company.

“I’d like to see some people go to jail,” said Patrick Leahy, a Democrat from Vermont. “This was a company that should have shut things down immediately.”

‘GAPING HOLE’

The FDA also puts a lot of faith in states that frequently conduct their own plant inspections, committee members said. States are not required to share the information with the agency.

“It seems to me that is one gaping hole,” said committee chairman Tom Harkin, an Iowa Democrat, who at one point waved peanut products in the air.

Harkin asked the FDA to release records to Congress detailing contracts and inspection reports with state departments of agriculture that check private companies.

The peanut outbreak is the latest in a series of incidents involving lettuce, peppers and spinach that have eroded public confidence in food safety and renewed calls for change at the FDA.

President Barack Obama this week promised a thorough review of the agency.

The current outbreak has led to the recall of more than 1,300 products ranging from crackers and pet food, and has involved dozens of manufacturers including Kellogg Corp and General Mills Inc. PCA last week expanded the recall to include all products made at the plant since January 2007.

Several bills have been introduced in Congress proposing food safety overhauls. The most popular focus on giving FDA more money and authority and splitting the agency to create a separate organization in charge of food safety.

“Many elements of a reform plan ... could be accomplished quickly and deliver real benefits to consumers,” said Caroline Smith DeWall, a director of food safety at the nonprofit Center for Science in the Public Interest.