Inorganic preservative levels in soil under treated wood decks after 8 years natural exposure in Borås, Sweden
P A Cooper, Y T Ung, M-L Edlund, J Jermer
Inorganic preservative components (Cu, Cr and As) were measured to a depth of 150 mm under deck structures made with Scots pine lumber treated with several different wood preservatives and installed in Borås Sweden 8 years ago. Higher contaminant levels were observed mainly under the drip lines and in the top 50 mm of soil. Under CCA treated decks, soil arsenic concentrations increased from background levels of about 3.5 mg/kg to 6-15 mg/kg in this zone. Copper and chromium levels were only slightly elevated above backgrounds of about 10 mg/kg and 3 mg/kg respectively. Copper levels were also only slightly elevated under decks treated with Tanalith E, Impralit KDS and Wolmanit CX-S. The Wolmanit CX-8 treated wood had concentrations averaging about 45 mg/kg in the top soil layer under the drip line while the Kemwood ACQ treated deck had concentrations above 100 mg/g in this zone.