Identification and quantitation of alkaloids in coca tea

Abstract

The consumption of coca tea is a common occurrence in many South American countries. The tea is often packaged in individual servings as tea bags which contain approximately 1 g of plant material. The consumption of coca tea leads to ingestion of cocaine and other alkaloids: however, there is little information available regarding the pharmacological or toxicological effects that result from consumption of coca tea. We performed a series of studies with coca tea bags from two South American countries, Peru and Bolivia. The alkaloidal content of the 'coca leaf' in coca tea bags was determined by two different extraction methods: Soxhlet extraction with methanol (exhaustive extraction), and mechanical agitation with methanol. Extracts were purified by solid-phase extraction (SPE) followed by analysis by gas chromatography/mass spectrometry (GC/MS). Coca tea prepared from Peruvian and Bolivian coca tea bags was also analyzed by SPE-GC/MS assay. In addition, urine specimens were analyzed from an individual who consumed one cup of Peruvian coca tea and one cup of Bolivian coca tea on separate occasions. Urine samples were analyzed by immunoassay (TDx R ) and SPE-GC/MS. Analysis of coca tea bags and coca tea indicated that cocaine, benzoylecgonine, ecgonine methyl ester and trans-cinnamoylcocaine were present in varying quantities. With exhaustive extraction, an average of 5.11 mg, and 4.86 mg of cocaine per tea bag were found in coca leaf from Peru and Bolivia, respectively. The average amounts of benzoylecgonine and ecgonine methyl ester in Peruvian coca leaf were 0.11 and 1.15 mg, and in Bolivian coca leaf were 0.12 and 2.93 mg per tea bag, respectively. trans-Cinnamoylcocaine was found in trace amounts in Peruvian tea bags and 0.16 mg/tea bag of Bolivian tea. When tea was prepared, an average of 4.14 mg of cocaine was present in a cup of Peruvian coca tea and 4.29 mg of cocaine was present in Bolivian tea. Following the consumption of a cup of Peruvian tea by one individual, a peak urine benzoylecgonine concentration of 3940 ng/ml occurred 10 h after ingestion. Consumption of Bolivian coca tea resulted in a peak benzoylecgonine concentration of 4979 ng/ml at 3.5 h. The cumulative urinary excretion of benzoylecgonine after approximately 48 h, determined by GC/MS, was 3.11 mg and 2.69 mg after consumption of Peruvian and Bolivian coca tea, respectively. This study demonstrated that coca tea bags and coca tea contain a significant amount of cocaine and cocaine-related alkaloids and the consumption of a single cup of Peruvian or Bolivian coca tea produces positive drug test results for cocaine metabolites.

Possibilities for discrimination between chewing of coca leaves and abuse of cocaine by hair analysis including hygrine, cuscohygrine, cinnamoylcocaine and cocaine metabolite/cocaine ratios

“…In contrast, the mean ratio EME/COC is about one order of magnitude higher for coca chewers, and there is almost no overlap between the ranges of both groups. This should be caused both by its high content in coca leaves [13][14][15][16] and by the enhanced hydrolysis of cocaine to EME in the chewing process.…”

“…Furthermore, low concentrations of tropinone were described [14,15]. Benzoylecgonine (1-2 % related to cocaine in coca tea bags [16]) seems not to be a natural alkaloid in coca leaf but is formed by hydrolysis of cocaine [12].…”

“…The content of alkaloids in coca leaves was qualitatively and quantitatively investigated several times and varies with coca species, age of the plant and the leaf, position in the leaf, soil composition, altitude of cultivation, longitudinal location, environmental factors, the time lapse between leaf harvesting and analysis and the conditions of storage [11][12][13][14][15][16][17][18][19]. The cocaine content of dried coca leaves is usually 0.4-0.7 % (w/w).…”

The Modern Art of Identification of Natural Substances in Whole Plants

“…The limit of detection of this method was 0.001 mg/L (Zou and Li 2006). GC coupled to mass spectrometry is also used for identification and quantification of alkaloids such as cocaine and its metabolites (Jenkins et al 1996).…”

Revisión sobre el uso del mate de hoja de coca en la prevención del mal agudo de montaña.

“…En el Perú, el mate de hoja de coca cuyo principal alcaloide es la cocaína, se sigue recomendando para prevenir el MAM; esta se comercializa en pequeñas bolsas filtrantes de 1 gramo de hoja de coca de la variedad Erythroxylum novogranatense que puede contener unos 4-5 mg de cocaína, al prepararse el mate en agua caliente se puede extraer hasta un máximo del 80% de la cocaína que contiene (11,12), la tasa de absorción gastrointestinal de cocaína ingerida es alrededor del 33% (13), lo que evidencia que hasta 1-1,3 mg de cocaína por bolsa filtrante sería absorbida al torrente sanguíneo. Esta cantidad es muy inferior a los 100 mg de cocaína vía endovenosa reportada en voluntarios no dependientes a cocaína para presentar efectos euforizantes, y a los 10 mg de cocaína para alcanzar concentraciones séricas de cocaína superiores a 100 ng/dL con la que se reportó efectos farmacológicos significativos para producir cambios pupilares, taquicardia, incremento de la presión arterial y cambios respiratorios por efecto adrenérgico (6,14,15).…”