No abstract

An analytical method is described for the determination of residues of CIPC, monuron, diuron, and linuron. After extraction from fruits and vegetable crops with acetone and partitioning into hexane, the herbicides are directly hydrolyzed and brominated to yield their respective brominated anilines. These derivatives are determined by electron affinity gas chromatography. Recovery of the herbicides from fruit and vegetables is good. The method is sensitive to about 0.02 p.p.m. of the herbicides.

No abstract

The insecticides in the raw hexane extracts were separated by gas chroma-tography and determined using a battery-operated, radium beta-ray cell as an electron affinity detector. In the work reported, a similar detector was used to determine residues of insecticides, herbicides, and fumigants in other crops, animal tissues, soils, and miscellaneous plant materials.

The 2,4-dichlorophenoxyalkanoic acids with aliphatic moieties ranging from butyric to undecanoic were metabolized by the soil microflora to acids of shorter chain length. Phenoxyalkanoic acids with an even number of carbons in the fatty acid consistently were converted to products with an even number of carbons while compounds with an odd number of carbons in the aliphatic moieties were converted to the corresponding 2,4dichlorophenoxyvalerate, propionate, and ultimately 2,4dichlorophenol as measured by gas chromatography. The results demonstrate a beta oxidation sequence in the degradation of these pesticides in soil.