BRUSSELS, Belgium – Phenylbutazone, or 'bute', residues found in horse meat is of low concern for consumers, according to two European Union agencies tasked with studying the issue.

In March, the European Commission asked the European Food Safety Authority (EFSA) and the European Medicines Agency (EMA) to assess the risks to human health from bute after horse meat was found in a variety of products throughout the EU, and the discovery of phenylbutazone in a small number of horse carcasses intended for human consumption.

Asda, a British supermarket chain owned by Wal-Mart, recently recalled its private-label canned corned beef product after tests revealed traces of bute above the 1 percent threshold established by the Food Standards Agency. Animals treated with the veterinary drug are prohibited from the food chain on concerns it may pose a risk to human health.

The agencies concluded that the low likelihood of exposure and the overall low likelihood of toxic effects meant that consumers shouldn't be too worried about bute found in horse meat. However, the agencies also said that it's not possible to set a threshold at which bute in food is safe.

"Phenylbutazone was previously evaluated by EMA in 1997 to establish maximum residue limits (MRLs) in food products of animal origin," the agencies reported. "The data available at that time did not allow a conclusion to be drawn on the level of phenylbutazone that could be considered safe in food of animal origin. As no MRL could be established, animals treated with phenylbutazone are not allowed to enter the food chain."

The agencies recommended measures to strengthen traceability and improve monitoring and reporting data of residues of veterinary medicines in live animals and food products of animal origin. Proposed EU-wide measures include introduction of a reliable identification system for horses, harmonizing checks of bute and improving the reporting of monitoring data for the presence of bute in foods.