As part of an effort to improve food-handling practices, federal officials have issued guidelines for reducing the number of home food-poisoning cases.

Douglas L. Archer, microbiology director for the Food and Drug Administration's Center for Food Safety and Applied Nutrition, reviewed several ways of minimizing risks at a recent conference.Primary among these is the need to eliminate cross-contamination, a situation where raw meats come in contact with cooked or ready-to-eat foods. This transfer of bacteria from potentially contaminated foods to wholesome ones can happen on cutting boards, utensils or in a food storage area such as a refrigerator.

One example of cross-contamination is the supermarket practice of stocking cooked shrimp alongside raw fish in seafood counters. The proximity of a cooked food to a raw item facilitates potentially dangerous bacterial transmission, Archer said.

Cross-contamination can also occur from hands and the FDA has frequently recommended that cooks wash with soap and hot water between preparation of each ingredient, particularly meats and seafood.

Archer also emphasized that foods need to be cooked at the proper temperature. Eggs heated until the whites harden, he said, would be sufficient to destroy any salmonella. Thorough heating will also destroy pathogens such as Listeria monocytogenes, Escherichia coli, Clostridium botulinum and Vibrio vulnificus in other foods.

"Eating raw meats and shellfish is not good and never has been," said Catherine E. Adams of the U.S. Department of Agriculture's Food Safety and Inspection Service. "And we need to convince people to not eat raw products."

Temperature variations are also an area that causes problems, said Archer. Oftentimes foods are left out too long before being refrigerated. Safety requires that cold foods should be kept below 40 degrees and hot foods heated to at least 165 degrees.

Storage practices are another potential hazard, such as when large amounts of prepared food are placed in a single container and then refrigerated or frozen. Frequently, bacteria will quickly multiply in the center of any such containers before the foods have properly cooled.

Archer recommends that cooked foods be divided into several smaller packages before being stored in the refrigerator. A similar principle applies for thawing: Frozen foods are not to be thawed over extended periods at room temperature. Instead, the items should be placed in the refrigerator, submerged under cold, running water or in a microwave oven.

Pets can also be a potential source of bacteria. They should be kept from food handling areas of the kitchen and not allowed to come in contact with food for human consumption.

Food is not the only place where bacteria may thrive.

Archer also says the pathogens can be found in sponges, dish towels, used paper towels, aprons, cutting boards, sinks, counter tops, wooden utensils and at the base of blender jars. Each of these should be cleansed thoroughly between usage or food preparation.

"Bacteria have been around longer than people. And if you give them enough time at the right temperature then bacteria will grow," he said.

Using a somewhat familiar theme to prevent carelessness in the home, Archer added that it is "people who cause illnesses, not germs."

(BU) Consumers, not manufacturers, are to blame for the majority of America's food-borne illnesses, according to federal health officials.

"The home is the most likely place for food contamination," said Archer. "Manufactured food accounts for a very small percentage of (these episodes)."

There are between 20 million and 40 million reported cases of food poisoning annually in the United States with the cost in medical bills, lost wages and product recalls as high as $10 billion, federal estimates show.

Archer's comments were echoed, in varying degrees, by several other government officials who made presentations at a Food Safety and Nutrition Update conference here, sponsored by the U.S. Department of Agriculture and FDA.

The cumulative message, in Archer's words, was that the United States has "the safest food supply in the world." And when illnesses occur it is often an instance of improper food handling, storage or cooking in the home, he said.

Despite the upbeat analysis, though, federal data indicates that there are increasing instances of microbiological contamination traced to conditions existing at the production stage of commodities such as meat, poultry, eggs, dairy and seafood. But health officials maintain that bacterial and viral threats, when they do exist, can be negated if only consumers observe sanitary practices in their own kitchens.

In explaining the agencies' current educational efforts, Catherine E. Adams, Ph.D., of the U.S. Department of Agriculture's Food Safety and Inspection Service said, "Consumers react when they are scared. Unfortunately, they don't respond to science."

However, some government representatives attending the conference privately acknowledged that industry trade group pressure on FDA and the U.S. Department of Agriculture is partially responsible for the decidedly positive view of the food supply's wholesomeness.

And several recent contamination instances, detailed at the gathering, show the scope of problems posed by harmful bacteria. They are:

-The presence of Salmonella enteriditis in raw and undercooked eggs caused two dozen deaths and thousands of illnesses from salmonellosis in the Northeastern and Mid-Atlantic states since health officials discovered a dramatic rise in such cases in 1984. Scientists now believe that the bacteria develops in the yolk before a shell is formed. Archer says that it will be two years before the contamination is brought under control.

-Incidents of Escherichia coli, a particularly virulent bacteria that can cause chronic kidney failure and bloody diarrhea, have risen sufficiently to cause the U.S. Department of Agriculture to intensify surveillance of beef for the pathogen's presence. The bacteria is believed to have caused an epidemic in Minneapolis after schoolchildren were fed precooked beef patties, a manufactured product that only required reheating before serving.

Archer believes that this particular strain of Escherichia coli is spreading from raw and undercooked beef raised in the Northwestern United States much in the same way that Salmonella enteriditis in eggs originated in the Northeast. While Escherichia coli is the fourth most common form of food poisoning nationally, it is the third most prevalent type in the Northwest.

-Federal officials are warning that the emergence of fully and partially cooked entrees in supermarkets can lead to increased incidents of Listeria monocytogenes. The products, some of which are also known as ready-to-eat foods, are particularly vulnerable to bacterial growth if there is improper storage. Part of the problem with Listeria monocytogenes is that it grows in the cold and that typical refrigeration temperatures are not sufficient enough to destory the pathogen.

The potential presence of Listeria monocytogenes in refrigerated meat products "concerns us," said Adams of the U.S. Department of Agriculture. Furthermore, government laboratory tests of production facilities and food items have found Listeria in all product categories.

-There have been several recent episodes where Clostridium botulinum has been linked to improperly stored, partially cooked vegetables such as garlic, onions and cabbage, said Archer. Botulism is a severe illness that is often fatal, was believed to be eradicated by proper canning techniques. But the latest episodes were linked to fried onions, garlic in oil, cole slaw and baked potatoes. In each case the food was stored in conditions that allowed the botulinum spores to develop. "We were surprised that botulinum could grow on garlic or onions, but bacteria change (over time), and they do it rapidly and adapt well," Archer said.

-The practice of feeding meat animals antibiotics or growth hormones continues to create controversy. The drugs, which are the same anabolic steroids used by some atheletes, promote muscle development and growth in animals. Over long periods of time, the compounds can create "super" or hard-to-kill bacteria. These pathogens, if consumed by humans via the meat, cause illnesses that do not respond to antibiotic treatment.

"When you feed antibiotics to animals you do create populations of organisms that are drug-resistant.