Undesirable substances in animal feed
Tuesday 26 June 2007
Undesirable substances (contaminants) are defined in legislation as 'any substance or product, with the exception of pathogenic agents, which is present in and/or on the product intended for animal feed and which presents a potential danger to animal or human health or to the environment or could adversely affect livestock production'.
In the main, these undesirable substances are either naturally occurring environmental contaminants which are present at low levels in feed and food products, particularly vegetable crops drawing nutrients directly from the soil, or process contaminants which may be introduced into the feeding stuff either during or as a consequence of its treatment, manufacture and storage. Examples include arsenic, cadmium, lead, mercury, aflatoxin B1 and dioxins.
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) – i.e., upper limits – for these substances and is transposed into law in England by regulation 14 of and Schedule 5 to the Feeding Stuffs (England) Regulations 2005 (as amended). Feed with levels above the MPLs is deemed to be unsafe and must be withdrawn and disposed of outside the feed and food chains (e.g., by sending it for alternative uses, for destruction, or returning it to the country of dispatch). Until 2003, it was possible to 'blend down' consignments of feed materials with levels of contamination above the MPL – i.e., to mix them with uncontaminated consignments in order to reduce the overall level of contamination to below the upper limit – but all feed products, including additives and premixtures, must now comply with the MPLs irrespective of any further processing which may be intended.
These controls extend beyond farmed livestock, and cover feed for pets, zoo and circus animals, and 'creatures living freely in the wild' (typically, seeds and peanuts for wild birds visiting domestic gardens). This is the only part of animal feed legislation that applies to wild creatures.
Many of the MPLs were established some time ago, and have not been revised in the light of current experience and scientific evidence. Following the ban on blending down, the European Food Safety Authority's CONTAM panel was asked to undertake a continuing review of these levels, and has since adopted a number of opinions setting out the latest evidence and (where appropriate) making suggestions for further action. It is then up to the Commission to consider adopting the opinions as formal proposals to amend existing MPLs and put them to a vote at the Standing Committee on the Food Chain and Animal Health.
Instances of advice from the CONTAM panel which has been transposed into legislation in the past few years, following a vote in the Standing Committee, include the relaxation of the limits for organic arsenic, which was considered to be less harmful than the inorganic form; the extension of controls on dioxins to include dioxin-like polychlorinated biphenyls (PCBs), the industrial use of which was prohibited some years ago but which remain present in the environment; and amendments to the MPLs for a range of organochlorine compounds, chiefly pesticides.
The CONTAM panel has also adopted opinions on three mycotoxins – deoxynivalenol, ochratoxin A and zearalenone – which can be present in cereals grown or stored under certain conditions. Following discussion with Member States on the incidence of these contaminants, the Commission has adopted a Recommendation setting out guidance values to assist with the monitoring and reporting of their actual presence in feed. The Food Standards Agency is currently drawing up a programme for the undertaking of this work.
There are similar controls on specified contaminants in food for human consumption, and the Agency has recently provided farmers growing cereals for human consumption with guidance on the control of mycotoxins, one of the category of contaminants in question. However, because these cereals may also be used for feed, this guidance is also of importance for livestock health purposes.