Significance of Metabolite Ratios in the Interpretation of Segmental Hair Testing Results—Differentiation of Single from Chronic Morphine Use in a Case Series Posted on September 10, 2021October 26, 2021 By Becky Carter Milena M. Madry, Sandra N. Poetzsch et al Metabolites; 11(8), 557; 2021 Download the article Seized Drugs/Controlled Substances, Toxicology