San Francisco ? Less than a week after the Food and Drug Administration lifted its warning on fresh spinach grown in California’s Salinas Valley, a popular brand of lettuce grown there has been recalled over concerns about E. coli contamination.

The lettuce does not appear to have caused any illnesses, the president of Salinas-based Nunes Co. Inc. said.

The lettuce scare comes amid other federal warnings that some brands of spinach, bottled carrot juice and recent shipments of beef could cause grave health risks – including paralysis, respiratory failure and death.

Executives ordered the recall after learning that irrigation water may have been contaminated with E. coli, said Tom Nunes Jr., president of the company.

So far, company investigators have not found E. coli bacteria in the lettuce itself, Nunes stressed. “We’re just reacting to a water test only. We know there’s generic E. coli on it, but we’re not sure what that means,” he said. “We’re being extra careful. This is precautionary.”

The recall covers Foxy brand lettuce purchased in grocery stores Oct. 3-6 in Arizona, California, Nevada, Washington, Oregon, Idaho and Montana. It was also sold to distributors in those states who may have sold it to restaurants or institutions.

The recalled lettuce was packaged as “Green Leaf 24 Count, waxed carton,” and “Green Leaf 18 Count, cellophane sleeve, returnable carton.” Packaging is stamped with lot code 6SL0024.

FDA spokeswoman Julie Zawisza said the agency is aware of the voluntary recall but had no details.

“As a standard course of action, we would expect the firm to identify the source of the contamination and take steps to … ensure that it doesn’t happen again,” Zawisza wrote in an e-mail.

It’s unlikely that the bacteria in the lettuce fields share the source of the E. coli found in spinach that has sickened nearly 200 people and has been linked to three deaths nationwide, Nunes said.

Pathogenic Escherichia coli bacteria, or E. coli, can proliferate in uncooked produce, raw milk, unpasteurized juice, contaminated water and meat. When consumed, it may cause diarrhea and bloody stools.

Although most healthy adults recover within a week without long-term side effects, some people may develop a form of kidney failure. That illness is most likely to occur in young children, senior citizens and people with compromised immune systems.