Until recently, standards for residual pesticides on foods were set by the Food Sanitation Law through “negative lists,” meaning that restrictions and prescribed usage standards applied only to those agricultural chemicals on the list. Positive lists, by contrast, prohibit the use of all agricultural chemicals, in principle, and indicate permissible residual levels only for those pesticides that may be used. Positive lists were introduced with the revision of the Food Sanitation Law in 2006.