Asda has recalled batches of its Smart Price corned beef after tests revealed low levels of veterinary medicine bute in some of the products.

All 340g tins of the item have been recalled with customers urged not to eat the product.

Asda had already withdrawn the same product just over a month ago when equine DNA was found. Further sampling has revealed the presence of low levels of phenylbutazone, which is used in veterinary medicine as a painkiller or anti-inflammatory.

A statement from Asda said: “In March 2013 we withdrew tinned Smart Price corned beef (340g) after receiving a positive test for horse DNA above the 1% trace level set by the Food Standards Agency (FSA).

“Tests on further batches have shown a positive result for very low levels of horse medication called phenylbutazone, also known as bute, at four parts per billion.

“The FSA has reassured us that the quantities we’ve found pose a low risk to human health.”

The grocer is also recalling tins of its Chosen By You corned beef as a precaution due to it being produced in the same factory, although it has not tested positive for phenylbutazone.

The FSA said no other Asda products are thought to be affected and that customers who had bought the corned beef should contact the supermarket for a refund.