Non-destructive, solvent-free quantification of wood preservatives in wood flour and wooden objects using GC-DTIMS

Qualitative and quantitative on-site detection methods for wood preservatives are of high value for the recycling industry and the occupational health and safety. Wood preservatives revealed as toxic to human and environment after decades of use. For the detection of contaminated wood and for processing of matured timber to particle boards a versatile detection method is needed. Especially historical wooden objects were treated with preservatives like pentachlorophenol, lindane or dichlorodiphenyltrichloroethane. This requires a nondestructive on-site detection method, that does not require specialized personnel. In this publication two methods are presented utilizing headspace sampling by solid-phase microextraction, subsequent separation using gas chromatography and detection by a drift tube ion mobility spectrometer (SPME-HS-GC-DTIMS). One method enables the quantitative detection of pentachlorophenol in wood flour and wood chips as they are used in wood processing industries. A limit of detection of 0.1 mg/kg was achieved using DIN 32645, which can be even more lowered. The second method enables non-destructive detection of pentachlorophenol, lindane, dichlorodiphenyltrichloroethane and other preservatives in wooden objects. Therefore, samples were prepared, which show a significantly lower concentration than typical treated objects, and used next to real samples for method validation. With the method contamination of the real samples and of the prepared samples of low concentration were proven.