They suspect it's responsible for thousands of food-related illnesses every year.
[Ads /]
They say the practice has been handed down from one generation to the next.
But the U.S. Dept. of Agriculture's Food Safety and Inspection Service has found it spreads bacteria like salmonella and campylobacter to other foods, utensils - and sometimes all over the kitchen.
Its study found 25-percent of side salads got contaminated by people washing poultry.
And it found bacteria on spice containers, cabinet and refrigerator doors, and many items in test kitchens.
"You can't rinse salmonella off by washing it under water. The only way to kill it is by cooking it to a safe internal temperature of 165 degrees," says Carmen Rottenberg, FSIS administrator.
[Ads /]
In addition to not washing poultry, the USDA says it's important to keep raw foods far away from cooked items.
And sanitize utensils, counters, as well as your hands, often.
Unfortunately the study also found many people may not be washing their hands well either.
75-percent of the study volunteers didn't wash their hands, even though they said they did.
For more on the USDA study, click here.