Thursday, 18 May 2017

Toxic pyrrolizidine alkaloids in herbal medicines commonly used in Ghana.

2017 Apr 18;202:154-161. doi: 10.1016/j.jep.2017.03.008. Epub 2017 Mar 8.

Author information

Institut für Lebensmittelchemie, Technische Universität Braunschweig, Schleinitzstrasse 20, 38106 Braunschweig, Germany.
Institut für Pharmazeutische Biologie, Technische Universität Braunschweig, Mendelssohnstrasse 1, 38106 Braunschweig, Germany. Electronic address:



Herbal medicines have been used for centuries for the management and treatment of various ailments due to the belief that they pose only little or no health risk and side effects, and also, in part, due to their availability, affordability and/or self-supply. However, the increasing information over the recent years on the occurrence of pyrrolizidine alkaloids (PAs) in honey, herbal food and tea products has raised concerns about the safety of herbal medicines with respect to contamination. To this day, little is known on the occurrence of toxic PAs in herbal medicines, especially in tropical West Africa. The aim of this study was therefore to determine the PA content of 70 well-known and widely patronized plant-derived medicinal preparations, which are commercialized in Ghana and some West African countries, in order to ascertain their potential health risk.


PAs of the herbal medicinal products, sourced from specialized drugstores and mostly regulatory approved, were analyzed for their PA content by a HPLC-ESI-MS/MS sum parameter method.


The results show that a total of 60% of the analyzed herbal products were PA positive, indicating an average PA-concentration of 25.0μg/kg. The maximum PA level (1290.0μg/kg) was attributed to a regulatory-approved herbal medicine not known, according to the list of declared ingredients, to contain PA-plant parts. Interestingly, higher PA content (average, 30.2μg/kg) was detected in regulatory-approved herbal medicines, in contrast to lower amount (average, 8.0μg/kg) detected in non-regulatory-approved products.


The findings of this study clearly demonstrate that herbal medicines containing PA plants as ingredients, as well as some of those containing plant species not known to produce PAs, are likely to contain hepatotoxic PA at levels higher than the daily dose in food and herbal medicinal products proposed by the European Medicines Agency (i.e. 0.35μg PA per day for 50kg adult and 0.14μg PA per day for 20kg children). Hence, regulatory authorities are advised to carry out more rigorous quality control tests with respect to PAs so as to minimize the exposure of the consumers to these toxic compounds.


Food safety; Ghana; HPLC-ESI-MS/MS; Herbal medicine; Pyrrolizidine alkaloid