Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on safety and efficacy of iron compounds as feed additives for all animal species: ferrous carbonate; ferric chloride, hexahydrate; ferrous fumarate; ferrous sulphate, heptahydrate; ferrous sulphate, monohydrate; ferrous chelate of amino acids, hydrate; ferrous chelate of glycine, hydrate.
A review of the literature concerning maximum safe levels in animals indicated that 450 mg total iron/kg appears to be safe for bovines and poultry, 600 mg total iron/kg for pet animals. These values are lower than the corresponding currently authorised maximum contents. Because of insufficient data, the FEEDAP Panel is not in a position to derive a maximum safe iron concentration in feed for horses or fish.
No concerns for consumer safety are expected from the use of the iron compounds under application in animal nutrition when used up to the EU maximum authorised level in feed.
Both ferrous sulphates and ferric chloride hexahydrate are corrosive upon contact with mucosae and considered as irritant to skin and respiratory tract. Ferrous fumarate, ferrous carbonate, ferrous chelate of glycine, hydrate and ferrous chelate of amino acids, hydrate are considered as irritants to skin, eyes and mucous membranes. Due to the presence of nickel, all additives under assessment should be considered as dermal and respiratory sensitisers and ferrous chelate of amino acids, hydrate also because of its proteinaceous nature.
Handling ferrous carbonate and ferrous fumarate may lead to an iron exposure by inhalation exceeding the threshold limit value. Users may be exposed to nickel by inhalation at levels exceeding the occupational exposure limit by more than one order of magnitude for ferrous fumarate, ferrous carbonate and ferrous chelate of amino acids hydrate; therefore, these additives pose a risk to users by inhalation.
The supplementation of feed with the iron compounds under assessment is not expected to pose an environmental risk.
The iron compounds under assessment, except ferrous carbonate, are considered efficacious sources of iron in animal nutrition for all species and categories. Ferrous carbonate has the potential to be an efficacious iron source for adult animals only.
The FEEDAP Panel made several recommendations concerning (i) the name of some of the additives; (ii) the specification of some additives; (iii) the characterisation of ferrous chelates of amino acids, hydrate; (iv) the monitoring of arsenic and nickel in the additives; (v) the currently authorised maximum iron content in complete feed to be reduced for bovines and poultry from 750 to 450 mg/kg, and for pets from 1,250 to 600 mg/kg; (vi) the protection of the user, particularly by reduction of exposure by inhalation; (vii) the use of ferrous carbonate in young animals; and (viii) the use of iron-based additives in water for drinking, which is seen as critical to ensure compliance with the legally established maximum supply of iron to animals.