The Wall Street Journal reports that federal regulators were investigating produce farming and packaging conditions in California’s Salinas Valley long before a company there was linked last week to a spinach-related E. coli outbreak. But their food-safety concerns extend beyond California to include farm areas in other states such as Arizona.

"We are bothered by what’s happening," said Robert E. Brackett, director of the Food and Drug Administration’s Center for Food Safety and Applied Nutrition. "All it takes is contamination at one time and it’s distributed to many people, and it becomes amplified."

As of yesterday, 109 cases, including one fatality, had been reported from 19 states, said David Acheson, the center’s chief medical officer. Salinas Valley, dubbed "the world’s salad bowl," has received the most attention only because of its size, Dr. Brackett said. Since 1995, the area was linked to at least eight of 19 E. coli outbreaks related to fresh-cut lettuce or spinach. But none of those outbreaks has been traced back to a specific grower, he said.

Initial evidence pointed to Natural Selection Foods LLC, of San Juan Bautista, Calif., which has voluntarily recalled its packaged spinach products, but Dr. Brackett said "there may be others involved."

A second company, River Ranch Fresh Foods LLC, of Salinas, Calif., is recalling three brands of its spring-mix salads: Farmers Market, Hy Vee, Fresh and Easy, the FDA said. The company, one of the biggest fresh-produce processors in the U.S., received bulk products from Natural Selection Foods.

For now, the FDA, which regulates fruits and vegetables, is urging consumers to avoid fresh spinach as well as cut, washed and bagged spinach. Ten of the 40 outbreaks related to fresh produce between 1998 and 2004 involved fresh-cut produce.

Last year, Dole Food Co. recalled 250,000 bags of salads after Minnesota buyers were affected with E. coli.

The industry has worked with the FDA to develop safety guidelines. The first, issued in March, called for employers to report infectious diseases and employees to wash hands and sanitize equipment, among others. Although voluntary, these measures have been adopted by most of the industry, Dr. Brackett said.