OCCURRENCE AND DETERMINATION OF PCH3-CONTAINING COMPOUNDS IN SURFACE-WATER

A procedure has been developed in which the presence of PCH3-containing compounds in surface waters can be detected in a sensitive and specific way. The compounds of interest are hydrolysed, yielding methylphosphonic acid as a common breakdown product. This acid is concentrated using an anion-exchange column and subsequently transformed into its dimethyl ester by diazomethane. After a clean-up on a microsilica gel column the ester is analysed by means of gas chromatography using a thermionic detector as a specific phosphorus detector. The lowest detectable concentration is approximately 1 nmol of a PCH3-containing compound per litre of water. Samples from the rivers Rhine and Meuse and from two lakes in the Netherlands were analysed. Concentration levels of 0.1 - 1 μg/l of PCH3-containing compounds expressed as methylphosphonic acid were found. The origin of the compounds and their possible accumulation in the environment are discussed. © 1979.