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A simple method is described for the quantitative determination of organochlorine pesticides and polychlorinated biphenyls (PCB's) in water at the sub‐ppb level. A micro gas‐phase extractor advantageously replaces other preconcentration and purification techniques. The extract is analyzed by capillary gas chromatography without further enrichment. The recovery at the ppb level was nearly 100% for organochlorine pesticides and more than 80% for PCB's. The complete procedure including sample preparation, steam distillation‐extraction, and capillary gas chromatographic analysis is carried out in less than four hours.

SummaryThis paper describes the results of a study on the deactivation of the surface of glass capillary columns by high temperature silylation (HTS).The different steps, leaching, washing, dehydration and HTS were optimized. A practical procedure yielding a high percentage of very good columns is given. The influence of leaching and HTS on the temperature stability and coating efficiency of capillary columns coated with OV-1 was studied. The inertness of the glass surface after HTS is demonstrated by several examples.

Methyl parathion (1, 3, 10 and 30 mg.kg-1) was injected intravenously in dogs and the serum concentrations were followed in function of time. For each dose the serum level data were fitted to a two- or tri-exponential equation by means of a non-linear least-squares regression analysis computer program. During the first hours after injection a rapid and important decrease of the serum levels was observed, whereas afterwards the levels decreased more slowly with a harmonic mean terminal half-life of 7.2 h (range 6.6-8.8 h) for the 10 mg.kg-1 dose. Simulations using the kinetic parameters obtained for the dose of 10 mg.kg-1 show that elimination of methyl parathion from the body is fast (5 h after injection only 30% of the dose is still present in the body) and that the fraction remaining is mainly located in the peripheral compartments.