A Study on the Development of Analytical Method for Polycarbamate by LC-MS/MS and its Decomposition Property in Sediment

An analytical method for polycarbamate in sediment by liquid chromatography tandem-mass spectrometry (LC-MS/MS) was developed. In this method, polycarbamate in sediment is methylated to ethylenebis dithiocarbamate dimethyl (EBDC-2Me) and dimethyldithiocarbamate methyl (DMDC-Me). Concentrations of polycarbamate are calculated from that of EBDC-2Me. The method detection limit (MDL) and method quantification limit (MQL) were 0.94 ng/g-dry and 2.57 ng/g-dry, respectively. The average recovery rate from sediment were 77.8% with a relative standard deviation (RSD) of 2.1%. Recovery rate was improved by the addition of methanol as solvent extraction in the case of organic-rich sediments. Polycarbamate added to sediment was completely lost for a day of preservation. In contrast, polycarbamate added to the crude extract was almost stable for three days of preservation, while it was completely lost for seven days of preservation. The concentrations of polycarbamate in the river and sea sediments sampled at Nagoya city were below the MDL.