A nationwide recall of 2 million pounds of pistachios in the wake of a salmonella scare has increased calls for more stringent food testing laws.

The contamination was only detected because of voluntary testing by a manufacturer for Kraft Foods Inc. almost two weeks ago. Private auditors hired by Kraft later found problems they think caused the contamination at a supplier's processing facility in central California.

If Kraft had not chosen to prioritize testing, 2 million pounds of pistachios that touched off government warnings and a scare this week probably would still be on the market. Neither the Food and Drug Administration nor state laws require food manufacturers to test the safety of their products.

"We're relying on companies to find the contaminated foods on their own, and since there's no national standards for this, some companies don't bother to test at all," said Rep. Diana DeGette, D-Colo., a critic of the nation's food safety system. "What if these nuts had been distributed by a company that doesn't test? We wouldn't have found out until people got sick."

DeGette and numerous other lawmakers want the FDA to monitor testing in all segments of the processed food industry, and for companies to be required to release test results.

Federal health officials warned people this week to avoid eating all pistachios and products containing them while they determine which products may be tainted. The nuts Kraft manufacturer Georgia Nut Co. tested on March 20 came from Setton Pistachio of Terra Bella Inc., the second-largest pistachio processor in the nation.

Inspection reports obtained by The Associated Press on Wednesday show the California plant had two minor violations when inspectors visited last year, none serious enough to cause a health risk. But the company's sister plant in New York failed a surprise inspection last month after state authorities found cockroaches and rodent droppings. A spokesman for both companies said the Terra Bella plant supplies pistachios to the facility in Commack, N.Y., but he declined to comment further.

The investigation of contaminated pistachios contrasts sharply with that in the salmonella outbreak that began late last year involving peanuts, the subject of a criminal investigation and thousands of recalls.

The problem was not traced to peanuts until hundreds of people around the country got sick. The company involved, Peanut Corp. of America, is under criminal investigation for allegedly shipping products it knew to be tainted. The company's owner has refused to answer questions from lawmakers, citing constitutional protections against self-incrimination.

Private industry reported the pistachio problem immediately, rather than waiting for public health officials to intervene. And as of Wednesday, authorities had not confirmed any illnesses.

"You can call it a fluke, you can call it good luck, or you can call it good judgment on the part of Kraft," said Dr. David Acheson, FDA's assistant commissioner for food safety. "They're not required to tell us. They did and we're moving on it."

Acheson said the FDA does not mandate testing so companies are free to decide whether to take that step before distributing food products to stores.

Officials with the Grocery Manufacturers Association, an industry group that represents major food manufacturers, say Kraft has one of the most aggressive food safety systems in the business.

But they say getting the government to require testing of all foods is not the answer, since different foods are at risk of becoming contaminated at very different steps in the manufacturing process.

"You don't want to do testing just for the sake of doing testing," said the association's chief science officer, Robert Brackett. "That tends to be this one-size-fits all situation where it may work really well for some products and not for others. What we really focus on is for companies to build the safety into their programs in the first place."