Tests of Packaged Greens Reveal High Level of Bacteria; Are Organic or Loose Greens Clean?
By Consumers Union on Tuesday, February 2nd, 2010
Alex Avery of the Center for Global Food Issues, a project of the Hudson Institute, has argued that organic greens actually will be dirtier because they are fertilized with manure. Organic farmers point out that they must use composted manure, which kills pathogens. In fact, Consumers Union‘s tests found no statistically significant difference between organic and conventional bagged leafy greens in terms of bacteria levels. This means that one can’t assume that packaged organic greens will be cleaner.
What about buying lettuce by the head, rather than as bagged salad? Won’t that at least avoid the possibility that dirtier greens will contaminate cleaner ones as they pass through the washes that are used in the packaging plants? At least one scientific study suggests that cross-contamination does occur, although on the other hand the chlorine in the washes is designed to knock down what microbiologists call the “bacteria load.”
But contamination can occur at other points in the process as well—disease-causing bacteria can be carried by irrigation water or by farm workers—which can affect heads just as easily as bagged lettuce. The E. coli 0157:H7 that appeared in spinach in 2006 and that resulted in three deaths and hundreds of illnesses may have come from the feces of a wild pig. USDA tested 3,828 samples of loose lettuce in 2005-6, and 3,117 samples of bagged lettuce in 2007-8 and the results for Salmonella were about the same: one percent positive for the bagged lettuce, and just under that, .7 percent for the loose lettuce. Thus there is no clear evidence that head lettuce is less likely to harbor bacteria than packaged salad greens
Consumers Union issued a report [PDF] today urging the U. S. Food and Drug Administration (FDA) to set safety standards for greens. FDA food safety legislation pending in the Senate—S. 510, the FDA Food Safety Modernization Act, and a similar bill passed last summer by the House of Representatives—would require the FDA to create both performance and on-farm standards to insure the safety of all leafy greens.
Bacteria are equal opportunity infectors. Because there are so many other advantages to local and organically grown produce, however, including less pesticide use and a generally smaller carbon footprint, Consumers Union, joins sustainable agriculture groups in supporting the Stabenow bill, S. 2758, which provides grants for small farmers and processors to receive appropriate food safety training, education, technical assistance, and extension services. Large operations have much easier access to these services.
Hopefully the Senate will pass both S. 2758, and S. 510 very soon.