Are There Antibiotics in Your Lettuce?:

You’re likely familiar with the fact that your lettuce could be contaminated with pesticides and even rocket fuel, but now researchers at the University of Minnesota have uncovered another risk: antibiotics.

Livestock are routinely given antibiotics to prevent disease outbreaks (which are common due to the typically crowded, unsanitary conditions in which these animals are raised). This, of course, means that conventional meat is loaded with antibiotics, some of which are passed through into manure.

The researchers found that, as one would expect, plants that are fertilized with antibiotic-containing manure uptake antibiotics into their leaves, tissue and roots. Root crops like potatoes, carrots and radishes may be particularly vulnerable, they said.

Consuming antibiotics via your salad could lead to allergies and the development of more antibiotic-resistant superbugs, among many other as yet unknown effects.

This time, however, eating organic is not the answer. Organic crops, which cannot be fertilized with synthetic fertilizers, are the ones most often fertilized with manure. As it stands, manure that contains antibiotics is still allowed under the organic label.

Journal of Environmental Quality July/August 2007, 36:1224-1230

Science Blog July 11, 2007