title: Sampling procedures and problems in determining pesticide residues in the hydrologic environment.
mesh_terms: D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D003634:DDT / Q000032:analysis; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis; D003632:Dichlorodiphenyldichloroethane / Q000032:analysis; D008722:Methods; D010573:Pesticide Residues / Q000032:analysis*; D012987:Soil / Q000032:analysis; D014481:United States; D014867:Water / Q000032:analysis; D014877:Water Pollution, Chemical / Q000032:analysis*
chemical_list: D010573:Pesticide Residues; D012987:Soil; D014867:Water; D003633:Dichlorodiphenyl Dichloroethylene; D003634:DDT; D003632:Dichlorodiphenyldichloroethane