Pyrrolizidine alkaloids in food: A challenge for agriculture and consumer protection
Various research projects and studies conducted by the official authorities of the federal states detected pyrrolizidine alkaloids in various samples of food and feed, in some cases in high concentrations. Due to their carcinogenic potential, 1-2 unsaturated pyrrolizidine alkaloids in particular should not be contained in food and feed. Against this background, the German Federal Institute for Risk Assessment is organising the 16th BfR Consumer Protection Forum "Pyrrolizidine Alkaloids - Challenges for Agriculture and Consumer Protection". "At this BfR Consumer Protection Forum, we intend to discuss the problem along the entire food chain with scientist and stakeholders", says Professor Dr. Dr. Andreas Hensel, President of the German Federal Institute for Risk Assessment (BfR). He explained that the goal of the event held in Berlin-Marienfelde on 3 and 4 December 2015 was to present the state of knowledge on the effects of pyrrolizidine alkaloids on human and animal health and to discuss the pathways via which these substances enter food and feed. However, the spread of pyrrolizidine alkaloid-containing plants in the environment and in agriculture is to be ascertained as well. Developing effective strategies for avoiding and minimising the transfer of these substances to food and feed is one of the most important goals from the viewpoint of consumer health protection. Apart from human health protection, the health of animals too is a topic to be explored at the BfR Consumer Protection Forum, since the ingestion of pyrrolizidine alkaloid-containing plants can lead to health problems, especially in grazing animals. In addition to experts from federal and state agencies, universities and other scientific institutions, representatives from agricultural, industrial and consumer associations will present their views on how to handle pyrrolizidine alkaloids in food and feed.
Pyrrolizidine alkaloids are secondary plant substances which a large number of plant species found worldwide produce as protection against herbivores. Their presence in plants varies greatly depending on plant species and part of the plant; it is also influenced by other factors such as climate and soil qualities. If high levels of these plant substances are ingested, this results in acute symptomatic liver diseases (Veno Occlusive Disease, VOD). Liver damage in humans has also been observed following several months of daily intake of moderate doses of pyrrolizidine alkaloids. Some pyrrolizidine alkaloids have additionally been shown to be genotoxic and carcinogenic in animal experiments.
Pyrrolizidine alkaloids have notably been detected in various herbal and other teas and in honey. It was found that high levels can be contained in herbal teas and in certain other types of tea. The reasons for this are only partially understood. One possible pathway is through pyrrolizidine alkaloids-containing wild herbs such as ragwort which are collected along with the raw materials for teas and herbal teas during harvest. However, the possibility of individual cases of plants used in certain teas forming these substances themselves is also being discussed. Pyrrolizidine alkaloids can also get into honey when bees collect the pollen and nectar of pyrrolizidine alkaloid-containing plants.
Agriculturally unused zones and extensification areas are significant. When bee populations visit plants in such areas, this can become a problem for honey producers (bee keepers), especially in the blooming period of June and July, because this is when the harvested honey can have high concentrations of pyrrolizidine alkaloids.
In terms of animal health, pyrrolizidine alkaloid-containing plants are important which grow in grazing areas and land where green fodder and soilage are cultivated or grow naturally or where they populate such areas from uncultivated areas. This also applies to extensified areas which are used as pastures kept to preserve the landscape. In such cases it is important to find ways to minimise the spread of these plants.
The 16th BfR Consumer Protection Forum aims to collate the state of knowledge about possible health risks arising from pyrrolizidine alkaloids for humans and animals. In addition, the analytical possibilities for the detection of pyrrolizidine alkaloids in food and feed and the carry-over of pyrrolizidine alkaloid to food will be illustrated. Effective strategies for avoiding contamination of food and feed with pyrrolizidine alkaloids will also be discussed.
About the BfR
The German Federal Institute for Risk Assessment (BfR) is a scientific institution within the portfolio of the Federal Ministry of Food and Agriculture (BMEL) in Germany. It advises the Federal Government and Federal Laender on questions of food, chemical and product safety. The BfR conducts its own research on topics that are closely linked to its assessment tasks.