“Bute” in horse meat presents very low risk to health, says England’s chief medical officer

BMJ 2013; 346 doi: (Published 15 February 2013) Cite this as: BMJ 2013;346:f1066
  1. Jacqui Wise
  1. 1London

England’s chief medical officer has tried to reassure the public about the safety of horse meat by announcing that someone would need to eat over 500 pure horse meat burgers a day to get close to acquiring dangerous amounts of phenylbutazone.

Phenylbutazone, known as bute, is a commonly used drug in horses. The Food Standards Agency said on 14 February that it had checked the carcasses of 206 horses slaughtered in the United Kingdom between 30 January and 7 February 2012. Eight tested positive for phenylbutazone, and meat from six of them may have entered the food chain in France.

But the chief medical officer, Sally Davies, said, “Horse meat containing phenylbutazone presents a very low risk to human health.”

Recent tests had shown the amount of phenylbutazone to be found was between trace levels and 1.9 mg/kg, she said. “At the levels of bute that have been found, a person would have to eat 500-600 100% horse meat burgers a day to get close to consuming a human’s daily dose. And it passes through the system fairly quickly, so it is unlikely to build up in our bodies.”

Phenylbutazone is a non-steroidal anti-inflammatory drug but because of its toxicity it is not used as a general analgesic in humans. However, it is effective in some severe forms of musculoskeletal and joint disorders, such as ankylosing spondylitis. It is recommended for use only in acute conditions after less toxic drugs have failed. The most serious adverse effects of phenylbutazone are related to bone marrow depression and include agranulocytosis and aplastic anaemia. Leucopenia, pancytopenia, haemolytic anaemia, and thrombocytopenia may also occur.

Davies said, “In patients who have been taking phenylbutazone as a medicine there can be serious side effects, but these are rare. It is extremely unlikely that anyone who has eaten horse meat containing bute will experience one of these side effects.”

The Department of Health said that it was working closely with the Food Standards Agency and the Department for Environment, Food and Rural Affairs to investigate how horse meat got into the UK food chain. They said that there is nothing to indicate a safety risk to consumers who may have eaten the products. However, they said that they support the advice of the Food Standards Agency that phenylbutazone should be excluded from the food chain.

Davies said, “There is currently no indication that phenylbutazone—bute—is present in any of the products that have been identified in this country, but the FSA has ordered further tests to confirm this.”

She added: “It’s understandable that people will be concerned, but it is important to emphasise that, even if bute is found to be present at low levels, there is a very low risk indeed that it would cause any harm to health.”

The European Union’s Standing Committee on the Food Chain has announced that it will draw up plans for large scale testing of beef products to check whether they contain horse DNA.


Cite this as: BMJ 2013;346:f1066