Here's what the Federal Food and Drug Administration says:

Washing fresh produce before eating is a healthful habit. You can reduce and often eliminate residues if they are present on fresh fruits and vegetables by following these simple tips:

• Wash produce with large amounts of cold or warm tap water, and scrub with a brush when appropriate; do not use soap.
• Throw away the outer leaves of leafy vegetables, such as lettuce and cabbage.

These washing steps should be followed for both conventional and organically grown produce to remove any pesticide residues, dirt or bacteria. Please remember to clean hands, scrub brushes or colandars before using to wash your fresh fruits and vegetables.