Abstract Thiamine mononitrate administered via feed or water for drinking is safe for the target animals having a wide margin of safety. The use of thiamine mononitrate as an additive in animal nutrition is safe for consumers. Since no data on inhalation toxicity of thiamine mononitrate has been provided, inhalation of dust is considered as potentially hazardous. Similarly no data is available on skin and eye irritation. Thiamine mononitrate is regarded as a skin and eye irritant. On the basis of published literature, thiamine should be considered as a sensitiser. A risk for the environment resulting from the use of thiamine mononitrate in animal nutrition is not foreseen. Thiamine mononitrate is regarded as an effective source of vitamin B1.