ANALYSIS OF BENZALKONIUM CHLORIDE IN THE EFFLUENT FROM EUROPEAN HOSPITALS BY SOLID-PHASE EXTRACTION AND HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY WITH POSTCOLUMN ION-PAIRING AND FLUORESCENCE DETECTION

A highly reproducible and specific method for the analysis of the quat ernary ammonium compound, benzalkonium chloride, in effluents from Eur opean hospitals is presented. Benzalkonium chloride was extracted with end-capped RP-18 solid-phase cartridges and was selectively eluted. T he resulting solution was analysed by high-performance liquid chromato graphy (HPLC). After elution from the analytical column of the HPLC sy stem, 9,10-dimethoxyanthracene-2-sulfonate was added continuously as a fluorescence marker, forming a hydrophobic ion-pair with benzalkonium chloride. The ion-pair was analysed by fluorescence detection. The me thod was applied to highly complex effluent samples from different siz ed European hospitals. The measured concentrations were between 0.05 a nd 6.03 mg/l. The amounts emitted per bed and year were 4.5-362 g and did not correlate with the size of the hospital. The total amounts wer e 2.6-909 kg/year.