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
Criticism of Tesco In September 2011 a Greenpeace report revealed that supermarkets in China, including Tesco, were selling vegetables that contained illegal pesticides or at levels exceeding the legal limit. 16 vegetable and fruit samples were taken from Tescos in Beijing and Guangzhou. Among them, 11 were found containing pesticide residues. One leafy vegetable sample turned up two kinds of pesticides, methamidophos and monocrotophos, the use of which have been prohibited in China since the beginning of year 2007. There have been several complaints against Tesco in Hungary, both by customers and employees. Two trade unionists employed by the company were dismissed in