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Assessment of 3-Nitrooxypropanol “3-NOP” as a feed additive for all ruminants for milk production and reproduction.

Morrison, Donald



A request was received to provide a full risk assessment on the safety and efficacy of an additive (Bovaer ® 10) containing a minimum 10% 3-nitrooxypropanol, under Regulation (EC) No 1831/20031 under the category of ‘zootechnical’ additives, functional group ‘substances which favourably affect the environment’. The additive is a preparation of a minimum 10% 3-NOP, aiming to supply a minimum of 52.8 mg 3-NOP and a maximum of 88 mg 3-NOP per kg of complete feedstuff (moisture content of 12%) for all ruminants for milk production and reproduction. The additive was fully characterised in the application and no causes for concern were identified by the AFFAJEG in the identity and characterisation.
The AFFAJEG concluded that the additive can be considered safe for the target species at a maximum dose of 200 mg/kg DM (176 mg/kg in complete feed), establishing a margin of tolerance of 2. An ADI of 0.3 mg/kg bw was established. Metabolism of 3-NOP produces 1,3 - propanediol in the rumen. Propanediol does not accumulate in the rumen and is not a cause for concern. Concentrations of 3-NOP and its metabolites in milk and edible tissues are not expected to reach levels of concern. The additive should be considered corrosive to the eyes, a skin irritant and potentially harmful by inhalation; it is not a skin sensitizer. It was concluded the additive poses an acceptable risk to the environment.
Based on data from in vitro studies, two meta-analyses and three long-term efficacy trials, the AFFAJEG concluded that the product can be considered efficacious for reducing methane production in ruminants when fed daily at the proposed dose of 52.8 - 88 mg/kg of complete feed.

Report Type Technical Report
Online Publication Date Apr 20, 2023
Publication Date 2023
Deposit Date Apr 9, 2024
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