Frequently Asked Questions

» Does USDA wash or peel the fruits and vegetables before testing them?
» Why are there any pesticide residues at all on organic food?
» Where did this data come from?
» Why are some of the pesticide levels shown as "N/A"?
» What’s the difference betweeen a pesticide and a pesticide residue?

Does USDA wash or peel the fruits and vegetables before testing them?
USDA tries to prepare the food the same way you would. Most foods are washed and/or peeled. As an example, with broccoli, they remove any damaged or wilted parts, remove the inedible portion of the stem, and then wash the broccoli before testing.

Why are there any pesticide residues at all on organic food?
Pesticides arrive even at organic farms by air, water and dust. There is sometimes enough arriving this way that it is detectable on organic food. Even when there is a detectable amount of pesticide on organic food, it is usually much smaller than the amount on conventionally grown food.

Where did this data come from?
From 1992 to 2008, the US Department of Agriculture (USDA) tested 93 different foods for pesticides. Since USDA often re-tests the same foods, and older tests aren't as relevant for the food you purchase today, this website contains data only from the test years 1999 to 2008. Note: As of April 5, 2011, when we conducted our 2011 update, USDA had not released new data as scheduled.

Why are some of the pesticide levels shown as "N/A"?
If there are fewer than five samples being used to calculate a percentage or a pesticide level, the calculation is highly variable, and possibly misleading. Therefore we show "N/A" instead of the possibly misleading result. The greater the number of samples, the more accurate the percentages and pesticide levels will be.

What’s the difference betweeen a pesticide and a pesticide residue?
Pesticides can break down into related chemicals. When this occurs, USDA often tests for the related chemicals as well as for the pesticide itself. Whatever pesticides and related chemicals are left on the food are collectively called "pesticide residues." Because "pesticide residues" can be a mouthful this website sometimes refers to "pesticides" when "pesticide residues" would be more complete and accurate.