China

2008 EPP fellow in Environmental Chemistry, Dr. Alfredo Alder

Tao Zhang
July - October, 2008
PhD student at Nankai University, China

During my stay at Eawag I did research on the development of a chemical analytical method for the detection of precursors of the perfluorinated compounds Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) in sludge and wastewater with LC-MS/MS. The aim of the work was to establish stable instrument parameters allowing reproducible measurements. Parameter setting has been finished for the following compounds: Perfluorooctanesulfonamide (FOSA), N-methyl per-fluorooctane­- sulfonamide (N-MeFOSA), N-ethyl perfluorooctanesulfonamide (N-EtFOSA), N-methyl perfluorooctanesulfonamidoacetic acid (N-MeFOSAA), N-ethyl perfluorooctane­- sulfonamidoacetic acid (N-EtFOSAA), 8:2 Fluorotelomer unsaturated carboxylic acid (8:2 FTUCA) and 6:2 Fluorotelomer unsaturated carboxylic acid (6:2 FTUCA). Detection limits of the instrument are around 1-4 pg.

Moreover, I started an experiment on sludge sample extraction and cleanup. During my experiments, I also encountered some problems, e.g. low sensitivity on N-methyl perfluorooctane-sulfonamido ethanol (N-MeFOSE) and N-ethyl perfluorooctanesulfonamido ethanol (N-EtFOSE) with LC-MS/MS, and lab contamination on Perfluorinated carboxylic acids (PFCAs). These issues need to be solved in the future.