Abstract: A composite wood product and methods for manufacturing the same and determining the concentration and distribution of an organic biocide within a composite wood product are provided. The organic biocide may be added to wood elements (i.e., fibers, flakes, strands, veneers) prior to consolidation and/or heating of the wood particles to form the composite wood product. A tracer additive may be mixed with the biocide, or applied separately to the furnish which is used to produce the composite wood product. The tracer additive may be detected via, for example, x-ray fluorescence. An amount of tracer additive detected may correlate to an amount of organic biocide within the wood elements and/or the composite wood product.