Scientific Opinion on the effect on public or animal health or on the environment on the presence of seeds of Ambrosia spp. in animal feed

The European Commission requested EFSA to provide a scientific opinion on the effect on public or animal health or on the environment on the further distribution of Ambrosia spp. in the European Union and on the importance of feed materials, in particular bird feed, in the dispersion of Ambrosia spp. The genus Ambrosia (Asteraceae family) is distributed worldwide. Ambrosia artemisiifolia (common ragweed) has heavily colonised several areas of South-East Europe. Ambrosia spp., both in their native range and in invaded areas, are of public health concern due to the allergenic properties of their pollen. The NDA Panel concluded that inhalation of the plant pollen causes rhino-conjunctivitis and asthma, with skin allergies and food allergy playing minor roles. Ambrosia may cross-sensitize patients to other allergens, including food allergens. There is some evidence for allergenicity of Ambrosia pollen in animals. With regard to the effects on the environment of the further distribution of Ambrosia spp. in the European Union, the PLH Panel concluded that there is no direct evidence that Ambrosia spp. cause extinction of plant species. However, there are some indications that A. artemisiifolia could become highly invasive in certain environmentally-valuable habitats and might be linked to an impoverishment of species richness, therefore further ecological studies are needed. The CONTAM Panel focused on the relative importance of animal feed, bird feed in particular, on the dispersion of Ambrosia. Ambrosia seeds may contaminate feed. However, animal feed materials compounded for use in livestock are extensively processed. This processing destroys Ambrosia seeds and hence the contribution of compounded feed to the dispersion of Ambrosia is considered to be negligible. Bird feed often contains significant quantities of Ambrosia seeds and remains unprocessed. Therefore, bird feed seems to play an important role in introducing Ambrosia to new, previously not infested areas.

© European Food Safety Authority, 2010

The genus Ambrosia (family Asteraceae) is distributed worldwide. In Europe, Ambrosia artemisiifolia (common ragweed) is the most common Ambrosia species and has heavily colonised several areas including the French Rhône valley, Northern Italy and South-East Europe (Bulgaria, Hungary, Southern Russia and Ukraine).

A. artemisiifolia is a weed of waste ground and agricultural land that flourishes wherever soil is newly disturbed. Dispersion of Ambrosia occurs naturally through seed drop, movement by animals and surface water, and often follows human activities entering the different regions by transport with agricultural machines and excavated material.

With regard to the effects on the environment of the further distribution of Ambrosia spp. in the European Union, the Panel on Plant Health (PLH Panel) concluded that there is no direct evidence that Ambrosia spp. cause extinction of plant species. However, there are some indications that A. artemisiifolia could become highly invasive in certain environmentally-valuable habitats and that under certain conditions, generally in habitats disturbed by human activities, A. artemisiifolia might be linked to an impoverishment of species richness, therefore further ecological studies are needed.

The Panel on Dietetic Products, Nutrition and Allergies (NDA Panel) concluded that the major adverse health effects of Ambrosia are related to the allergenicity of inhaled plant pollen causing rhino-conjunctivitis and asthma, with skin allergies and food allergy playing minor roles. Ambrosia may cross-sensitize patients to other allergens, including food allergens.

The Panel on the Contaminants in the Food Chain (CONTAM Panel) noted that there is some evidence for allergenicity in animals, particularly in relation to the obstructive airway diseases in horses. There is no evidence that Ambrosia species form secondary plant metabolites that are of clinical significance for livestock.

Animal feeds, including maize, wheat, sunflowers, millet, peanuts, soybean, peas and beans may contain seeds of Ambrosia. Commercial feed for livestock is processed prior to use and the procedures of grinding, pelleting and/or heating almost completely destroy the Ambrosia seeds.  In contrast, bird feed used for the feeding of wild and ornamental birds, which is often contaminated with seeds of A. artemisiifolia, is generally not processed and hence may contribute to the dissemination of viable ragweed seeds.

The CONTAM Panel noted that the contribution of processed commercial feed materials to the further dispersion of Ambrosia seems to be negligible as seeds are destroyed during the processing of compound feeds. In contrast, the CONTAM Panel concluded that bird feed may be an important route of ragweed dispersal especially in not infested areas. Therefore, the prevention of the use of contaminated bird feed is likely to contribute to an attenuation of the further dispersion of Ambrosia in Europe.

Allergenicity, Ambrosia, animal toxicity, bird feed, dispersal, distribution, ragweed