Pyrrolizidine Alkaloids – Hidden Toxins in Food and Medicinal Plants
It is well known that food (such as salad mixtures or honey) can be contaminated with pyrrolizidine alkaloids. But also some medicinal plants such as comfrey (Symphytum officinale), butterbur (Petasites) and coltsfoot (Tussilago farfara), used in medicinal teas, have been reported to contain pyrrolizidine alkaloid and their N-oxides. Some of these pyrrolizidine alkaloids act as hepatotoxic, mutagenic and/or cancerogenic agents after oral consumption and produce some modifications in the human metabolism. Typical representatives are echimidine, senecionine and senkirkin. The legislature has therefore decided that plants and preparations thereof can only be sold if it is guaranteed that the maximum daily intake of pyrrolizidine alkaloids remains below 1 microgram. Reference substances are required for identification and a reliable quantitative analysis by PhytoLab has characterized a total of 20 different pyrrolizidine alkaloids and pyrrolizidine alkaloid N-oxides as primary reference substances according to international guidelines.