2013 horse meat scandal only found more than 1% horse DNA in Asda's tins of but it also contained four ppb of phenylbutazone, marking the first time since the start of the scandal that bute had been detected in a meat product in the UK food chain. However, one problem raised was over documentation; all of the UK animals with phenylbutazone contamination tested in early 2013 possessed a "horse passport" that allowed the carcasses to be sold for human consumption. The veterinary residues committee (VRC) reminded the public in July 2012 that it had been "repeatedly expressing concern" about phenylbutazone contamination. and recent discoveries
Tesco Ireland UK, but not doing the same in Ireland. This is putting pressure on prices in Ireland as surplus poultry meat from the UK is being dumped on the market. The Irish Advertising Standards Authority in January 2009 found that Tesco Ireland advertising was misleading. Britain's Advertising Standards Authority said a leaflet produced by Tesco Ireland Ltd, was ‘‘irresponsible’’ and breached clauses in the advertising code on substantiation and weight control in May 2010. Tesco pleaded guilty and was fined, after sending unsolicited marketing emails to a number of customers and for having a problem with the email "opt-out" option. The