To prevent food-borne illness, the FDA recommends that perishable food be out no more than two hours, or one hour in temperatures above 90 degrees. Food that sits out longer should be tossed, said Joan Miller, extension educator at Michigan State University Extension.

The bacteria responsible for foodborne illness – E. coli 0157, Salmonella, Listeria, Campylobacter – can wreak havoc on the gastrointestinal tract and, in some cases, lead to serious illness and death.

Picnickers can reduce the chance of food poisoning still further by observing a few simple rules:

• Keep cold food cold, in insulated coolers with gel packs, when carrying it in and out.
• Pack coolers full, to keep the temperature down.
• When possible, use separate coolers for beverages, which will be opened frequently, and perishables, which should remain closed.
• Wash hands with soap and water in the outdoors, and make sure all food handlers do the same.

Another potential source of cross-contamination is the ubiquitous kitchen sponge. Ideally, Miller said, sponges should be allowed to dry between uses and replaced once a week. Consider using dish towels rather than sponges, she suggested. Launder the towels frequently in hot water and allow them to dry completely between uses.

The USDA also recommends not rinsing meat. Bacteria on the surface will be killed when the meat is cooked, and the rinsing process may contaminate utensils and countertops.