Use of comprehensive two-dimensional gas chromatography for the broad screening of hazardous contaminants in urban wastewaters.

The list of priority chemicals included in various regulations such as the European Water Framework Directive, as well as the list of hazardous contaminants identified in the aquatic environment, are increasing at an accelerated pace. Therefore, there is a need for broad spectrum methods capable of simultaneously determining hundreds, if not thousands, of contaminants. For the analysis of non-polar or semi-polar contaminants, comprehensive two-dimensional gas chromatography (GC x GC) is more powerful than conventional gas chromatography thanks to a separation on two different stationary phases. This paper reports the use of GC x GC for a broad screening of hazardous contaminants in an urban wastewater plant. Comparison between the raw and treated wastewater has been carried out using a semi-quantitative approach. A variety of drugs, personal care products, pesticides, carcinogens and compounds toxic for reproduction, were identified. Most of these compounds were removed or decreased by this wastewater treatment plant. Preliminary results from this single plant will need to be confirmed by a more extensive study before drawing conclusions on the removal efficiency of 2D-GC amenable compounds.