 Each country adopts their own agricultural policies and Maximum Residue Limits (MRL) and Acceptable Daily Intake (ADI).The level of food additive usage varies by country because forms of agriculture are different in regions according to their geographical or climatical factors.Pre-harvest intervals are also set to require a crop or livestock product not be harvested before a certain period after application in order to allow the pesticide residue to decrease below maximum residue limits or other tolerance levels.