WASHINGTON, D.C. ? Soft lunch boxes may be lined with a vinyl containing lead, the government says, but safety officials say the containers pose no immediate danger.

Food and Drug Administration officials have told companies to look for a manufacturing technique that does not use lead, which can cause learning disabilities and behavioral problems.

Mitchell Cheeseman, associate director of the FDA’s Office of Food Additive Safety, noted that because food in lunch boxes generally is stored inside bags, the potential for contamination is minimized.

Consumer Product Safety Commission spokeswoman Patty Davis said Friday her organization’s tests showed the lunch boxes were safe for children to handle.

According to the commission’s results, children would have to rub their hands on the lunch box and then lick their hands more than 600 times a day for 15 to 30 days in order to be exposed to a dangerous amount of lead.