research Contribution Of In-Utero Drug Exposure When Interpreting Hair Results In Young Children 1 citations, June 2014 in “Annales de Toxicologie Analytique” Hair analysis alone can't confirm long-term drug exposure in children under 1 year old.
research Disappearance of Tramadol and THC-COOH in Hair After Discontinuation of Abuse: Two Different Profiles 7 citations, January 2019 in “Journal of Analytical Toxicology” Tramadol and THC-COOH can be detected in hair for several months after stopping use.