Ethical champion Felicity Lawrence has struck another blow to the fresh produce industry, revealing the abuse of migrant workers picking clementines Italy.

Published on the front page of the Guardian today (Tuesday), Lawrence’s article entitled Bitter fruit: The dark side of the Christmas orange harvest, exposes the “20,000 undocumented workers” bringing in the Christmas clementine harvest in southern Italy.

She highlighted poor living conditions, where African migrant workers live in damp dark factories, “six or seven to each windowless room”. According to Lawrence, many have no access to running water or sanitation and sleep on beds made of cardboard and old doors.

They then get up before dawn to pick oranges and olives for supply to the UK and northern Europe, with wages as low as €11 a day as the market price for citrus falls below the cost of production in Italy.

She quoted a report by charity Medecins sans Frontieres (MSF), which sent a team to assess the situation in Calabria.

The report found that most migrants' living conditions did not meet minimum standards set by the UN high commissioner for refugees, for refugees living in African camps.

More than 40 per cent lived in abandoned buildings and 36 per cent in crowded houses sharing mattresses, she said.

More than 50 per cent had no access to running water and toilets, and where available, toilets could be shared by 100 people.

Of 770 workers, some 94 per cent had at least one medical problem and three quarters had chronic diseases.

“Skin diseases resulting from poor hygiene and exposures to pesticides were rife,” she said, “as were respiratory infections, including some TB, the latter found particularly among the Romanian population.

“Many of the workers could only afford to eat once a day and were consuming fewer calories than they needed for the eight-10 hours of hard manual labour they worked.”

She also stated that 30 per cent had been subjected to violence, “mostly in the form of beatings by Italians.”

An MSF spokesman said: “It may seem surprising that MSF needs to work in mainland Europe, but we were shocked by the conditions of migrants here. Italy is not a victim of this migration. They are needed by the agriculture in the area, which wants cheap labour to produce cheap food. This is the hypocrisy of the system.”