ANALYSIS OF THE DITHIOCARBAMATE FUNGICIDES ZIRAM, MANEB, AND ZINEB AND THE FLOTATION AGENT ETHYLXANTHOGENATE BY ION-PAIR REVERSED-PHASE HPLC

Although large quantities of dithiocarbamate fungicides and ethylxanth ogenate mineral flotation agents are released routinely to the environ ment, little is known about their fate and effects because sensitive a nalytical techniques are not available. A simple and selective HPLC me thod for trace level analysis of dithiocarbamate fungicides and xantho genates (dithiocarbonates) in natural waters has been developed. The m ethod is based on the in situ formation of a 1:1 Cu(II)-dithioligand c omplex and its separation as an ion pair with hexanesulfonate on a C-1 8 reversed-phase column. The compounds are detected at the wavelength of maximum absorption of the Cu(IT)-ligand complex (260-287 Mn), Metho d detection limits are 20 nM dimethyldithiocarbamate (i.e., 3 mu g/L Z iram), 33 nM ethylenebis(dithiocarbamate) (i.e., 9 mu g/L Maneb), and 23 nM ethylxanthogenate (i.e., 4 mu g/L), An on-line preconcentration step can be used to lower the detection limits by a factor of 5-10.