Surveys still suck.

But at least researchers from the U.S. Food and Drug Administration recognize the limitations of self-reported food safety behavior, in this case applied to produce washing practices in the kitchen. From a recent paper in Food Protection Trends:

“Although washing does not guarantee removal of pathogens if the item has become contaminated, it increases the likelihood that pathogens will be removed, compared with not washing or using washing methods that are not recommended. Soaking and use of any type of cleaner are not recommended washing methods. Soaking does not remove contami¬nants as effectively as rubbing or rinsing produce under running water. Cleaners not meant for produce can introduce chemical contaminants, and produce washes are considered no more effective than water. Unlike other types of produce, almost all bagged, pre-cut let¬tuce in the market place is pre-washed. For bagged, pre-cut lettuce that is labeled as pre-washed, additional washing is not recommended as it is not likely to en¬hance safety and introduces the op¬portunity for cross-contamination of the product with pathogens that may be in the home kitchen. …

“This study has some strengths and limitations. One of the limitations is that the data are self-reported. We rely on consumers’ ability to both remember what they do and convey it accurately. Self-reporting is also subject to the de¬sire to give socially desirable responses; an observational study of consumer produce washing showed that far fewer consumers actually wash produce than report doing so in surveys. Also, the findings would have been more use¬ful if we had asked consumers why they washed cantaloupes and bagged, pre-cut lettuce. Finally, our survey suffered from the increasingly common problem of low response rates for household sur¬veys, although this does not necessarily bias the survey results. Some of the main strengths of this study are the sampling method, large sample size and weighting strategy, which allows our findings to be representative of the population. This allows us to make comparisons at the population level.

“Food Safety practices should be¬gin on the farm and be rigorously ap¬plied along the entire chain so that food products are safe for human consump¬tion without the need for extraordinary measures. Consumers, however, are the critical endpoint along the food supply chain. Educational efforts with respect to product washing should focus on explaining why it is important to wash hard rind produce such as cantaloupe be¬fore cutting, but not rewashing produce that is ready to be eaten.”

The abstract is below:

Consumer vegetable and fruit washing practices in the United States, 2006 and 2010
Food Protection Trends, Vol. 32, No. 4, Pages 164–172
Linda Verrill, Amy M. Lando 1 and Kellie M. O’Connell
Vegetables and fruits may become contaminated with pathogens anywhere along the farm-to-plate continuum. Therefore, the FDA recommends that vegetables and fruits that have not already been washed be washed by the consumer before slicing or consuming them. The FDA included in its 2006 and 2010 Food Safety Survey a series of questions about purchasing and washing of strawberries, tomatoes, cantaloupes, and bagged, pre-cut lettuce. The Food Safety Survey is a telephone survey tracking consumers’ knowledge, attitudes and behaviors related to food safety. In 2006, of those who buy these products, 98% wash strawberries, 97% wash tomatoes, 57% wash cantaloupes and 54% wash bagged pre-cut lettuce. Overall, for both years, more women than men wash cantaloupes, and more men than women wash bagged pre-cut lettuce. Cantaloupe washing declined from 2006 to 2010 for men, while lettuce washing increased for women in the same period. Targeted education campaigns should emphasize the importance of washing produce, especially fruits with hard rinds.