Weathering is the cause of numerous damages for outdoor joineries. Protection of wood using a preservative treatment covered with a coating is a process widely used to limit these damages. However, biocides from preservative treated wood are prone to degradation and leaching, having a direct influence on the joinery service life. This document deals with extraction and analytical methods for biocide characterization from Use Class 3 treated woods and collected rain runoffs. Analysis by gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) showed limits of quantification (LOQs) in the order of microgram per litre of injected solution, equivalent to hundreds of nanograms per gram of treated wood. Accelerated Solvent Extractions (ASE) using acetone, and final extract re-concentrated in ethyl acetate were performed with wood powder spiked at three levels of concentration, resulting in satisfying extraction efficiencies between 70% and 130%, except for fenpropimorph which exhibited a low extraction efficiency close to 20%. Another series of extraction with methanol led to good extraction efficiency including fenpropimorph (83% ± 7%). Online Solid Phase Micro Extraction (SPME) coupled to a GC-MS/MS method developed for water analysis led to LOQs in the order of nanogram per litre of extracted water. This water analysis method was used to study wood preservatives depletion from the first rain runoff samples collected during a weathering test. Three wood preservative products were selected for a surface treatment of Scots pine sapwood panels. Samples were exposed outdoors on stainless exposure racks connected to jerrycans for rain runoff collection. Severe exposure settings, with uncoated panels and a 45° inclination, were deliberately chosen in order to maximise climatic factor responsible for wood preservatives depletion. Quick losses were observed in runoffs from uncoated panels, while leaching from coated panels was reduced and more stable. Significant differences in preservative compound leaching were noticed among biocides, from concentrations in the range of mg/L for propiconazole in first rain events, to concentrations close to LOQs for pyrethroids.

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