title: DDT moratorium in Arizona--agricultural residues after seven years.
abstract: The moratorium on agricultural use of DDT in Arizona that began in January 1969 proved very effective during the first 7 years of enforcement. Residues on green alfalfa declined significantly to a probable inherent level of 0.02 ppm wet weight. Soil residues of sigmaDDT-related degradation products declined significantly, averaging 23 percent; residues in desert soils declined 60 percent. The sigmaDDT half-life in irrigated soils was about 7 years; it decreased to 2.5 years in nonirrigated soils.
mesh_terms: D001130:Arizona; D002849:Chromatography, Gas; D003634:DDT / Q000032:analysis*; D000455:Medicago sativa / Q000032:analysis; D010573:Pesticide Residues / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D013997:Time Factors
chemical_list: D010573:Pesticide Residues; D012987:Soil; D003634:DDT