Occurrence of pyrrolizidine alkaloids in food

Last updated:
7 May 2014
The European Food Safety Authority (EFSA) Panel on Contaminants in the Food Chain (CONTAM) has assessed the risk for public and animal health related to the presence of Pyrrolizidine alkaloids (PAs) in food and feed. In response to this, the UK has commissioned a project on PAs in tea, herbal supplements and honey.
Study duration: January 2014 to December 2014
Project code: FS102056
Contractor: Food and Environment Research Agency (Fera)


Pyrrolizidine alkaloids (PAs) are toxins found naturally in a wide variety of plant species. More than 350 PAs are known. Numerous plant families express PAs, some species expressing several PAs and there are some PAs that are expressed by several plant species.

One of EFSA’s recommendations was to collect more occurrence data on PAs in food. Since the alkaloids are genotoxic and carcinogenic, EFSA was unable to set a tolerable intake.

It is envisaged that this study will analyse 250 samples of herbal teas, as well as herbal supplements and honey. These data on PAs in food sold in the UK will enable the FSA to identify and assess any food safety issues from consuming these products.

Research Approach

Samples of herbs and honey will be analysed using the two procedures that have given the best performance and are currently undergoing international testing (liquid chromatography-mass spectrometry, LCMS, and liquid chromatography time-of-flight mass spectrometry, LC-TOF-MS). This allows for a wide quantitative screen of many PAs. Samples will be analysed for about 15 ragwort type alkaloids, 20 comfrey/echium alkaloids and 5 pyrrolizidine alkaloids of other types (eg riddeline, monocrotaline, tussilago).

Analysis of the levels of PAs in infusions of about 25 samples of teas that are known to have the highest levels of PAs and those that are most likely to be consumed will also be carried out.


Additional Info


Published Papers