PESTICIDE-RESIDUE LEVELS IN SOILS AND CROPS, 1971 - NATIONAL-SOILS-MONITORING-PROGRAM .3

  • 1 January 1978
    • journal article
    • research article
    • Vol. 12  (3) , 117-136
Abstract
Data from the 1971 National Soils of Monitoring Program are summarized. Composite samples of soil and mature crops were scheduled for collection from 1533 4-hectare sites in 37 USA states. Analyses were performed on 1486 soil samples for organochlorines, organophosphates, polychlorinated biphenyl and elemental As; samples were analyzed for atrazine only when pesticide application data indicated current-year use. Organochlorine pesticides were dected in 45% of the soil samples in the following order of frequency: dieldrin, .SIGMA.DDT, aldrin, chlordane and heptachlor epoxide. Most pesticide levels ranged 0.01-0.25 ppm. Crop samples were collected from 729 sites, and all were analyzed for organochlorines. Crop samples were analyzed for organophosphates and atrazine only when pesticide application data indicated current-year use. Organochlorines were detected in 42% of the crop samples analyzed, organophosphates in 13%, and atrazine in 1%.