Examples include arsenic, cadmium, lead, mercury, aflatoxin B1 and dioxins.
Generally, these undesirable substances are either naturally-occurring environmental contaminants that are present at low levels in feed and food products, particularly vegetable crops drawing nutrients directly from the soil, or are process contaminants that may be introduced into the feeding stuff either during or as a consequence of its treatment, manufacture and storage.
The presence of undesirable substances in feed is controlled by European Parliament and Council Directive 2002/32/EC of 7 May 2002 (as amended), which sets maximum permitted levels (MPLs) for these substances and is given effect in England by regulations 8 and 9 of the Animal Feed (England) Regulations 2010. (Separate but parallel legislation applies in Scotland, Wales and Northern Ireland.) Feed that contains a contaminant at a level above the relevant MPL is deemed to be unsafe and must be withdrawn and disposed of outside the feed and food chains, for example by sending it for alternative uses, for destruction, or returning it to the country of dispatch. The 'blending down' of consignments of feed materials with levels of contamination above the MPL – mixing them with uncontaminated consignments in order to reduce the overall level of contamination to below the upper limit – is prohibited.
These controls apply to feed for both food-producing and non-food-producing animals – that is, feed for farmed livestock (including horses and rabbits), fish, pets, laboratory, zoo and circus animals, and creatures living freely in the wild.
Directive 2002/32 and amendments to Annex I (providing the list of undesirable substances, animal feed products affected and maximum permitted limits) can be found on the Eur-lex website (see 'External sites' links on this page).
The European Food Safety Authority's Panel on Contaminants in the Food Chain (CONTAM) carries out assessments of the safety of various contaminants according to new scientific data. The latest opinions from CONTAM can be found on the EFSA website (see 'External sites' links).
EFSA’s opinions are considered by the Commission and Member States when deciding whether or not a contaminant should be subject to legislative controls. If EFSA's opinion highlights a need for some sort of control of the contaminant, for example because of potential risk to the animal, consumer, worker, environment, or a need for further data on occurrence of the contaminant, the Commission will consider whether legislative controls are necessary. The proposal is then presented to the Standing Committee on the Food Chain and Animal Health (SCoFCAH) and Member States vote on the European Commission’s proposal. If a Qualified Majority Vote in favour is achieved, the proposal is adopted as an amendment to the Directive. Agendas and minutes of meetings of SCoFCAH may be viewed on the EC website. The FSA has published separate guidance on mycotoxins (including aflatoxin B1), which can be found on our website.