The Food Standards Agency has dismissed claims that the horse drug 'bute' may have entered the human food chain in horsemeat.
The FSA said horses treated with the drug phenylbutazone are "not allowed to enter the food chain".
The FSA statement added: "During the recent horsemeat incident the Food Safety Authority of Ireland checked for the presence of phenylbutazone and the samples came back negative."
Shadow Environment Secretary Mary Creagh earlier expressed fears that the drug may have entered the food chain through horsemeat slaughtered in UK abattoirs
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