The 110 California-grown commodities tested had an even better safety record. Of the 1,134 samples of California produce, 98.6 percent, or 1,118 samples, complied with allowable limits.

“We collect samples from large grocery stores, mom-and-pop shops and wholesale outlets throughout the state,” Reardon explained. “In addition to most frequently consumed fruits and vegetables like apples and lettuce, we sample tomatillos, cactus leaves and other produce used in ethnic cooking.”

In 2009 and 2010 combined, DPR detected illegal pesticide residues most frequently on tomatillos, limes, papayas, chili peppers and bitter gourds from Mexico; spinach from California; and ginger from China.

In 2010, six commodities - bok choy, celery, table grapes, kale, peaches and spinach - were tested for residues by both the multiresidue screen technology and LC/MS.

In 2011, LC/MS will be used to test apples, strawberries, peaches, potatoes, spinach and long beans.

Civil penalties can be imposed against repeat illegal pesticide residue offenders. For example, California-based distributor Cal Fresco LLC was fined $10,000 in August 2010 for importing produce from Mexico with residues of insecticides not registered for use on these crops. Although illegal, the residues were at such low levels that they did not pose a health risk. A press release about this enforcement action is posted at:

The 2010 pesticide residue monitoring data and previous years are posted on DPR’s website at:

A fact sheet, “Pesticides and food: how we test for safety,” which includes information about how consumers can reduce exposure to pesticides in food, is posted at: