This is due to the dissipation of residues between the farm and marketplace and the standard food preparation techniques applied prior to testing. The PDP report breaks down residues into preharvest and postharvest applications. Residue data for fresh versus processed products can be dramatically different, as in the case of green beans. Residue detections are fewer in apple juice than in fresh fruit, except for carbaryl and dimethoate. This may be due to the variety of apples chosen for processing into juice and dissipation of residues during processing.
Canned peaches show generally lower residues than fresh product.
PDP compared U.S. and Chilean grapes and peaches from 1994-1996 and U.S. and Mexican tomatoes in 1996 and 1997. More presumptive tolerance violations were found in Chilean grapes and peaches while the numbers of violations for tomatoes were exactly the same between the U.S. and Mexico. The participating states were California, Florida, Michigan, New York, Ohio, Texas, Washington, Colorado, Maryland, Wisconsin and North Carolina.