Emerging formulations of preservatives made with micronized basic copper carbonates with azoles and/or quat to control copper tolerant fungi have been used to replace formulations containing soluble copper to reduce the leaching of copper and the corrosion of metal in contact with wood. This study proposes to use laboratory soil leaching test AWPA standard (E20-08) to estimate the amount of copper soluble and mobile in micronized copper azole treated southern pine at 6.7Cu kg/m3 and micronized copper treated quat at cu retention of 3.3 kg/m3. treated wood were exposed to different soils with pH ranging from 4.7 to 8 for 12 weeks to evaluate the amount of copper leached from treated wood to soil. About 10% of initial copper was leached from MCQ treated wood to soil with pH 4.7 while only 2.0% cu were leached in soil with pH 8. For MCA, 9.6% and 0.6% were leached in soil pH 4.7 and 8, respectively, clearly indicating that copper from MCA and MCQ treated pine can be leached with higher amount at low acidic pH. Slightly more copper was leached from MCQ treated wood compare to MCA.

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