Destructive and non-destructive methods for the evaluation of chlorinated pesticides concentration and emissions from wooden art objects

Liquid solvent extraction with dichloromethane combined with liquid injection gas chromatography-mass spectrometry (GC-MS) is a well suited method for determination and quantification of chlorinated pesticides in wood tissue. By scaling down the extraction step to micro level, concentration profiles of the pesticides in the wood tissue can be acquired. For this, wood tissue sections with a thickness of 50 µm are prepared with a sliding microtome. The sections are extracted in GC vials with dichloromethane and further analyzed by GC-MS. Chlorinated pesticides can be detected and semi quantified non-destructively on wood surfaces by µ-X-ray fluorescence (µ-XRF). Emissions of pesticides from contaminated art objects can be measured by emission chamber experiments followed by thermal desorption GC-MS analysis of the sampled volatiles. However emission chamber experiments are often difficult to realize, as they are cost intensive, time consuming and the objects need to be transported to the emission chamber. Passive sampling with polydimethylsiloxane (PDMS) can be used alternatively for easy-to-do on-site sampling of pesticide emissions from art objects to further qualify and quantify the emissions by thermal desorption GC-MS.