340 Original article Coca tea consumption causes positive urine cocaine assay Suzan S. Mazor a , Mark B. Mycyk b , Brandon K. Wills c , Larry D. Brace d , Leon Gussow c and Timothy Erickson c,e Background Coca tea, derived from the same plant that is used to synthesize cocaine, is commonly consumed in South America and easily obtained in the United States. Objectives To determine whether consumption of coca tea would result in a positive urine toxicology screen for cocaine metabolites. Methods Five healthy adult volunteers consumed coca tea and underwent serial quantitative urine testing for cocaine metabolites by fluorescence polarization immunoassay. The cutoff for a positive assay was chosen at 300 ng/ml, the National Institute on Drug Abuse standard. Results Each participant’s urine cocaine assay was positive (level exceeding 300 ng/ml) by 2 h after ingestion. Three out of five participants’ samples remained positive at 36 h. Mean urine benzoylecgonine concentrations in all postconsumption samples was 1777 ng/ml (95% confidence interval: 1060–2495). Conclusions Coca tea ingestion resulted in a positive urine assay for cocaine metabolite. Healthcare professionals should consider a history of coca tea ingestion when interpreting urine toxicology results. European Journal of Emergency Medicine 13:340–341  c 2006 Lippincott Williams & Wilkins. European Journal of Emergency Medicine 2006, 13:340–341 Keywords: assay, benzoylecgonine, coca tea, cocaine, mate de coca a Division of Emergency Medicine, Department of Pediatrics, Children’s Hospital and Regional Medical Center, Seattle, Washington, b Department of Emergency Medicine, Northwestern University School of Medicine, c Toxikon Consortium, Departments of d Pathology and e Emergency Medicine, University of Illinois at Chicago, Chicago, Illinois, USA Correspondence and requests for reprints to Dr Suzan S Mazor, MD, Division of Emergency Medicine, Children’s Hospital and Regional Medical Center, 4800 Sand Point Way NE, Seattle, WA 98105, USA Tel: + 1 206 987 5616; e-mail: suzan.mazor@seattlechildrens.org Received 16 November 2005 Accepted 22 March 2006 Introduction Coca tea, or mate de coca, is commonly consumed in South America and is marketed as an aid to altitude adjustment. The tea, also found in restaurants in the United States, is made from the leaves of the coca plant, Erythroxylum coca, the same plant used to harvest cocaine. Previous studies have demonstrated that cocaine can be extracted from Health Inca tea (Enaco, Peru, South America), one brand of mate de coca [1]. Hospital toxicology screens primarily assay metabolites of a handful of parent drugs. Screens are subject to false- positive and false-negative results and require interpreta- tion on the basis of the patient’s reported history [2]. The hospital screen for cocaine measures benzoyl- ecgonine. As coca is metabolized to benzoylecgonine, we sought to determine whether consumption of a commercially available tea made from coca leaves would result in urine benzoylecgonine concentrations high enough to result in a positive hospital screen for cocaine metabolites. Methods Institutional Review Board approval was obtained. Coca tea was prepared using commercially available Delisse (Enaco) mate de coca tea bags from Peru. Each tea bag was steeped in 8 ounces of water for 15 min. Five healthy volunteers (four men and one nonpregnant woman) consumed coca tea over 15 min. A standard serving of tea is 8 fluid ounces; participant A consumed a single 8 ounce cup of tea, participant B consumed two cups, participant C consumed three cups, participant 4 consumed four cups and participant 5 consumed five cups. All volunteers were in good health; all denied using any drugs of abuse, medications or supplements. Urine samples were collected from each participant before ingestion (control), and at 2, 12, 24 and 36 h after ingestion. Urine toxicology assays for benzoylecgonine were performed by fluorescence polarization immuno- assay using Abbott AxSym system (Abbott Laboratories, Abbott Park, Illinois, USA). The cutoff for a positive assay was chosen at 300 ng/ml, the National Institute on Drug Abuse standard. Results Control urine benzoylecgonine concentrations ranged from 0 to 10.5 ng/ml. At 2 h after ingestion, the urine concentration of benzoylecgonine exceeded the positive reporting threshold (300 ng/ml) in 5/5 (100%) partici- pants. Three out of five participants’ samples remained positive at 36 h. Mean urine benzoylecgonine concentra- tions in all postconsumption samples was 1777 ng/ml 0969-9546  c 2006 Lippincott Williams & Wilkins Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.