Development and validation of a method for determination of trace levels of alkylphenols and bisphenol A in atmospheric samples

A method has been developed and validated in order to assess the occurrence of the alkylphenols tert-octylphenol and the isomers of technical nonylphenol as well as bisphenol A in gasphase and aerosol samples of a remote area. Gasphase samples were adsorbed to XAD2 resin, aerosol samples were taken on glass fiber filters. After ultrasonic extraction, clean-up by column chromatography and silylation of the analytes, ten nonylphenol peaks were quantified separately using a GC-MSD-SIM method. The absolute limits of detection and determination are in the range of a few pg per compound, which is a prerequisite for the quantification of the analytes in relatively unpolluted air. The precision of the whole analytical method is in the range of 1–17% and the recoveries range from 57% to 80%. Problems were encountered during method development due to the tendency of the analytes to sorb to glass surfaces. Silanisation of glassware was crucial to achieve acceptable recoveries. The widespread use of the analytes in plastic resins resulted in sample contamination. For this reason a careful choice of sampling material was necessary. Measured concentrations in gasphase samples (lower nanogram per m 3 range) and aerosol samples (upper picogram per m 3 range) are one to three orders of magnitude below already published concentrations.