While they are generally considered safe, the actual effectiveness of these washes is debated. Even if they remove surface residues, one can't be sure that all pesticides have been eliminated. And some evidence suggests water is actually good enough. In a study of three commercial washes, University of Maine researchers found that distilled water was equally if not more effective in removing microbes such as bacteria and mold. Another study at Tennessee State University also found that water worked as well as the vegetable wash tested.
And yet, we know that produce washes give some people peace of mind. If this is the case in your household, you don't need to shell out a ton of money for commercial products. You can make your own spray using ingredients you probably already have in your pantry. A solution of equal parts white vinegar and water can dissolve residues and kill bacteria; just spray it on, rub, and rinse with water. For other simple solutions, see Re-Nest's How To: Make Your Own Fruit and Vegetable Wash.
How do you wash fruits and vegetables?