Advances in removal of chromated copper arsenate elements in wood waste, contaminated water and soils

Chromated Copper Arsenate (CCA) is a water-based mixture of heavy metals widely used as a timber preservative. Despite its efficacy in prolonging the lifespan of treated wood, CCA has become a subject of environmental scrutiny due to the leaching of toxic components into surrounding soil and water.

CCA components in soil have been reported with levels as high as 3,300, 2,800 and 2,100 mg/kg for As, Cr and Cu, respectively; way above the recommended levels of 12, 64, 63 mg/kg for agricultural soils. Therefore, the use of CCA as a wood preservative has been restricted in most developed countries. Developing countries, however, continue to utilize CCA treated wood as utility poles.  The elements of CCA have potential health risks upon dermal contact with CCA residues from treated structures as well as exposure from contaminated soil and water.