Washington ? Coming to school menus nationwide: Tainted burgers, fruit and other foods? Reported outbreaks of school-related foodborne illnesses have been rising about 10 percent a year, a congressional study said Tuesday.

The General Accounting Office recommended better coordination among federal agencies that inspect food plants with the state and local agencies that buy most food for schools.

Outbreaks have been traced to a variety of products, including strawberries, milk, hamburgers, spaghetti sauce and fish sticks.

In 1999, the latest year for which data are available, 50 school-related outbreaks were reported nationwide with 2,900 illnesses, GAO said. Accounting for changes in reporting methods, GAO estimated that reported outbreaks increased 10 percent annually during the 1990s.

About 27 million meals are served in schools each day.

Officials don’t know how many outbreaks were caused by lunches served in cafeterias as opposed to food pupils brought from home, but it is believed that school-provided meals were the culprit in most of the cases.

The Agriculture Department heavily subsidizes school lunches and buys 17 percent of the food that is served. State and local agencies buy the rest. USDA “provides little guidance” to those agencies to ensure that the food they are buying is safe, GAO said.