Determination of trichloroanisole and trichlorophenol in wineries' ambient air by passive sampling and thermal desorption-gas chromatography coupled to tandem mass spectrometry.

The present paper describes the calibration of selected passive samplers used in the quantitation of trichlorophenol and trichloroanisole in wineries' ambient air, by calculating the corresponding sampling rates. The method is based on passive sampling with sorbent tubes and involves thermal desorption-gas chromatography-triple quadrupole mass spectrometry analysis. Three commercially available sorbents were tested using sampling cartridges with a radial design instead of axial ones. The best results were found for Tenax TA™. Sampling rates (R-values) for the selected sorbents were determined. Passive sampling was also used for accurately determining the amount of compounds present in the air. Adequate correlation coefficients between the mass of the target analytes and exposure time were obtained. The proposed validated method is a useful tool for the early detection of trichloroanisole and its precursor trichlorophenol in wineries' ambient air while avoiding contamination of wine or winery facilities.

On the estimate of capillary electrophoresis blanks: application to detection limits evaluation as recommended by IUPAC.

A new method to obtain the signal associated with an electrophoretic blank is presented to be included in the calibration procedures. The signal assigned to the blank is obtained by direct integration of the background noise using extrapolated values of the base-peak width at different concentrations in order to obtain the zero concentration. Detection limits that are better adjusted to a statistical evaluation are thus implemented, as recommended by the International Union of Pure and Applied Chemistry (IUPAC). The detection limit has been examined for a series of linear alkyl benzenesulfonates (C10-C13) and total linear alkyl benzenesulfonates that are widely used in many different commercial products.