Risk assessment of the consumption of a pyrrolizidine alkaloid containing indigenous vegetable crotalaria brevidens (mitoo)

Potential risk from the consumption of leaves of Crotalaria brevidens, an indigenous leafy vegetable of the Lake Victoria basin of East Africa, was assessed. Wild and cultivated forms of this indigenous vegetable contained two major pyrrolizidine alkaloids on thin layer chromatography, but in quantities that were too small to quantify by ¹H Nuclear Magnetic Resonance or Ultraviolet spectrometry. Based on the detection limits of these methods and dietary data from Tarime District, Tanzania, we estimate the Potential Weekly Intake of the vegetable during the peak season of consumption to be 305 ug/week/person. This does not account for detoxification during cooking. While the nutritional benefits of this vegetable likely outweigh any detrimental effects of the alkaloids, the recognized hepatotoxicity of these compounds may outweigh the benefits under some circumstances.

Key words:

• Pyrrolizidine alkaloids
• toxicity
• indigenous leafy vegetable
• Crotalaria brevidens
• East Africa