Skip to main content
U.S. flag

An official website of the United States government

Migration of iron and manganese into CCA-treated wood in soil contact and the resulting error in leaching results when using energy dispersive x-ray fluorescence spectrometers

Informally Refereed

Abstract

In a laboratory leaching study, we found that chromated copper arsenate (CCA) treated wood, which had been exposed to one of five soils examined, unexpectedly appeared to gain significant Cr (47%) when measured with an energy-dispersive x-ray fluorescence instrument (American Wood-Preservers' Association (AWPA) Method A9-01 2001). Analysis of some of the leached samples exposed to all five soils by inductively coupled plasma (ICP) spectrometry showed that Fe migrated into the CCA-treated samples from four of the five soils and Mn migrated into wood exposed to two of the five soils. The presence of Fe and Mn interfered with measurement of Cr retention using two different bench-top energy dispersive x-ray fluorescence spectrometers. It has been previously shown that Mn and/or Fe can migrate from soil into wood, and we conclude that this may result in a significant error in determining the amount of metals that leach from CCA- treated wood. Thus, AWPA Method A9-01 may need to be modified to indicate this potential error, and leaching data from prior studies that used energy dispersive instruments may need to be reexamined.

Keywords

CCA, iron, manganese, leaching, x-ray fluorescence spectrometers

Citation

Schultz, Tor P.; Nicholas, Darrel D.; Lebow, Stan. 2003. Migration of iron and manganese into CCA-treated wood in soil contact and the resulting error in leaching results when using energy dispersive x-ray fluorescence spectrometers. Forest products journal. Vol. 53, no. 9 (Sept. 2003): Pages 77-80.
https://www.fs.usda.gov/research/treesearch/8437