The BfR is currently conducting a research project on “Determination of Pyrrolizidine Alkaloids in Food and Feed”. Initially, various samples of off-the-shelf tea, herbal tea and medicinal tea were examined. As the first results of the non-representative tests, a total concentrations of 0 to 3.4 milligrams of pyrrolizidine alkaloids per kilogram of analyzed sample were found.
“We measured unexpectedly high levels of pyrrolizidine alkaloids in some of the tea and herbal tea samples,” says BfR President Professor Dr. Dr. Andreas Hensel. “As data from animal experiments uncovered the detected pyrrolizidine alkaloids as genotoxic carcinogens, the levels are too high and should possibly be reduced”
These include analysis of tea and herbal tea batches prior to marketing but also causal research by the economic operators. Despite the unexpectedly high levels in some of the samples, acute health damage to adults and children is unlikely if consumed over short periods. If, however, higher than average consumption of products currently measured with medium and high levels of pyrrolizidine alkaloids is maintained over longer periods, a risk to health could result, especially for children, pregnant women and nursing mothers if the current data is validated. Because there are considerable fluctuations in the concentrations of individual samples, however, even with teas of the same variety, it is currently impossible to make a definite statement regarding the health risk resulting from continous intake of contaminated tea infusions. Our initial recommendation is therefore that parents do not exclusively give their children tea and herbal tea. Expectant and nursing mothers should also consume tea and herbal tea alternately with other beverages. The first data collected in the research project have to be be verified by Food monitoring authorities.