Each pesticide or pesticide class comes with a specificset of environmental concerns. Such undesirable effectshave led many pesticides to be banned, while regula-tions have limited and/or reduced the use of others. Overtime, pesticideshavegenerallybecomelesspersistentandmore species-specific, reducing their environmental foot-print. In addition the amounts of pesticides applied perhectare have declined, in some cases by 99%.