Most fresh produce samples analyzed by the California Department of Pesticide Regulation in 2011 had no detectable pesticide residues, and residues that were detected generally fell well below allowable limits, the department has announced.

The department collected 2,707 samples of more than 160 types of domestic and imported produce in 2011 from large and small grocery stores and wholesale outlets throughout the state. Analysis showed that:

• 61 percent had no detectable residues.

• 36 percent had residues within allowable limits set by the U.S. Environmental Protection Agency.

• 3 percent had illegal residues, but at levels that posed no acute health risk. Most of the samples with illegal residues were imported.

• 36 percent of the samples were grown in California, and 98 percent of them were in compliance.

When illegal residues are found, DPR removes the produce from sale. For example, an illegal pesticide residue on a peach led to more than 2.4 million pounds of peaches removed from the market, and the department fined two San Joaquin Valley pesticide dealers for selling a product for a use not allowed by the label.

In 2010 and 2011 combined, DPR detected illegal pesticide residues most frequently on snow peas from Guatemala; tomatillos, chili peppers, limes, and papaya from Mexico; ginger from China; and spinach and kale from California. Data for 2011 and previous years are posted at the department's Web site.

California has been analyzing produce for pesticide residues since 1926. In 2011, nearly 25 percent of the samples were analyzed by new technology, liquid chromatography mass spectrometry (LC/MS) that expands the number of pesticides that can be detected, including recently registered pesticides. Costs of the analysis are covered by a special fund generated by fees on sales of pesticides used in California, and registration and license fees.

For more information, check the fact sheet Pesticides and food: how we test for safety.