Press Release

Foodborne Illness: Fresh Produce the Most Frequent Offender

Jun 16, 2008

Foodborne Illness: Fresh Produce the Most Frequent Offender

FOR RELEASE: June 16, 2008

Stan Wellborn, RFF Director of Public Affairs, 202-328-5026
Sandra Hoffmann, RFF Fellow, 202-328-5022

WASHINGTON - As revelations about tainted tomatoes and other fresh products continue to generate headlines and scare consumers, a report by researchers at Resources for the Future shows that produce is the most common cause of food-related maladies in the United States - and has been for many years.

In a recent survey of top scientists on the sources of foodborne illness in the United States, fresh produce emerged as the leader in the number of cases among major food groups.

Published in the Journal of Food Protection, the survey involved leading U.S. food safety experts from academia, government, and industry - bringing backgrounds from microbiology, veterinary medicine, food technology, public health, and epidemiology.

"The study asks highly experienced food safety scientists to estimate how many of the illnesses caused by each of the 11 leading foodborne pathogens, including Salmonella and E. coli O157:H7, are associated with consumption of different types of food," said RFF Fellow Sandra Hoffmann, who has studied food safety issues over many years. "Our data clearly identifies produce as the top culprit in the number of cases of foodborne illness among American consumers."

Foodborne pathogens of all types have been estimated to cause as many as 76 million illnesses and 5,000 deaths in the United States each year. In their study, RFF researchers Hoffmann and Alan Krupnick and Paul Fischbeck from Carnegie Mellon University found that produce caused 29.4 percent of foodborne illness, followed by seafood at 24.8 percent, poultry at 15.8 percent, and processed meats at 7.1 percent. Bread, dairy products, eggs, beverages, beef, pork, and game resulted in much smaller incidences of illness.

"Based on our research, we are not surprised to see that foods like spinach and tomatoes are among the products being blamed for recent illnesses," says Hoffmann. "While many consumers presume that contaminated meat causes most cases of food poisoning, the fact is that fresh produce is as serious a problem."

The study uses a methodology known as expert elicitation that is standard practice in engineering research, but new to estimating food threats. It provides a structured approach to eliciting expert judgment on the probability of rare events. Expert elicitation is needed to look at foodborne illness because the Centers for Disease Control and Prevention (CDC) provide systematic annual data only on outbreaks, which account for only 10 percent of all foodborne illness. "It's difficult to collect data on the remaining scattered, sporadic illnesses. It's even harder to get direct evidence on which foods caused these illnesses, but experts know a great deal about food processing, handling, and biology that can inform a solid judgment," says Hoffmann.

She adds, "Our study provides the first attribution estimates for the United States that systematically capture the remaining 90 percent of cases. Expert judgment is a good supplement to primary data and research, but we'd be thrilled if our work were a catalyst for improving surveillance and reporting on the sources of foodborne illness." The most recent CDC estimates of total foodborne illness by pathogen were published in 1999.

The paper, entitled "Using Expert Elicitation to Link Foodborne Illness in the United States to Foods," was published in the Journal of Food Protection, Volume 70, Number 5, 2007.


Resources for the Future, an independent and nonpartisan Washington, DC, think tank, seeks to improve environmental and natural resource policymaking worldwide through objective social science research of the highest caliber.


Founded in 1952, Resources for the Future is an independent and nonpartisan institution.