Cell wall microdistribution of chloropicrin and methylisothiocyanate in treated spruce
G F Daniel, B Goodell
Chloropicrin and methylisothiocyanate (MIT) residues were observed using SEM/EDXA and TEM/EDXA in treated spruce wafers that had been exposed to the vapors of the two fumigant preservatives. Chlorinated residues from chloropicrin were found throughout the wood cell wall, even in acetone extracted material. The residues were most heavily concentrated in extractive materials in the rays, but unlike previous work, no preferential binding to the middle lamellae lignin was noted. This could be a reflection of the different wood species used, or because of the SEM techniques used previously. Sulfur residues from MIT were also observed throughout the wood cell wall of wood treated with this fumigant. Preferential binding of MIT residues to the middle lamellae cell corners was noted in the TEM/EDXA analysis of the samples, suggesting possible preferential binding of MIT residues to the lignin component of the middle lamellae.