The Ethical Trading Initiative (ETI) urges UK food retailers to trace through their supply chains after it uncovered the exploitation of migrant workers in Italy's tomato crop.

In Britain, 60 per cent of its tomatoes are sourced from Italy, however the ETI has uncovered that the crop's supply chain is victim to mafia involvement, reports Supply Management.

The ETI has published a report entitled 'Counteracting exploitation of migrant workers in Italian tomato production', which states that although it has tried to rid the sector of this problem, the migrant workforce is still struggling under Caporali, or illegal gangmasters.

Italy banned this Caporalato system four years ago following the discovery of working conditions and links to organised crime, but still the supply chain is littered with illegal activity.

Nick Kightley, ETi's food and farming adviser said: "Reliance on migrant workers, and the employment illegalities inherent within the tomato sector, has massive knock-on implications for those UK retailers that want to ensure their supply chains are abuse free."