"US: Dirty Dozen list "misleading"
Growers point to the fact that pesticide levels are kept below tolerances established by the Environmental Protection Agency (EPA), which are measured in parts-per-million and typically include a 100-fold safety margin.
EWG says its rankings are based on the pesticide contamination or–lack thereof–in 48 popular fruits and vegetables based on 28,000 samples tested by FDA and the US Department of Agriculture.
Source: foodsafetynews.com