CHROMATOGRAPHIC DETERMINATION OF PHOSPHINE (PH3) AND HYDROGEN-SULFIDE(H2S) IN THE HEADSPACE OF ANAEROBIC BACTERIAL ENRICHMENTS USING FLAMEPHOTOMETRIC DETECTION

A gas chromatographic method is presented which distinguishes phosphin e from hydrogen sulfide and other possible headspace gases of anaerobi c microbial cultures. In anaerobic cultures spiked with phosphine, thi s gas is recovered in the liquid and gaseous phase down to 10 pg per m l of gas or liquid. No biogenically produced phosphine was found. Phos phine in amounts as small as 30 ng per 1 can be stored for several day s in glass bottles covered with rubber septa, filled with nitrogen, in the presence or absence of water or of an anaerobic bacterial culture . Due to the selectivity of the detector and the retention characteris tics of the porous layer open tubular polymer column alkanes, alkenes and organosulfur compounds routinely found in anaerobic bacterial head spaces do not interfere with the analytical quantification of phosphin e.