Exploitation in the food industry is alive and well. That's according to the latest grim report by the Joseph Rowntree Foundation which studied the experiences of some of the migrant workers (almost invisibly) toiling in our fields, factories and restaurants.

According to the report's authors, who interviewed more than 60 migrants - from China, Latvia, Lithuania and Poland - many of Britain's hidden army of overseas workers live in a climate of fear, are subjected to inhumane conditions, racism, sexism and bullying, and forced to work long hours for less than the minimum wage.

Some have paid (presumably steep) fees to agents in order to secure the work in the first place, but quickly find themselves continually indebted to gangmasters who - in an apparently widespread scam -'overhire' the number of workers needed, in doing so providing just enough employment for each to repay their debts, but keeping migrants locked in a cycle of poverty and exploitation. Such are the levels of despair some migrants have been driven to self harm, according to the foundation.

The extensive survey mirrors the findings of a recent investigation by the Ecologist magazine, which uncovered similarly unpleasant exploitation in some of Britain's fields, glasshouses and packhouses, and revealed how two major suppliers of fruit and vegetables to retailers have been accused of serious exploitative practices and poor health and safety.

The story of one migrant worker I interviewed, Irena Jaysenka (not her real name), is as disturbing as it is typical:

"People are treated like cattle, not human beings, I never expected it could be like this" she told me. Irena's from Lithuania who until the summer last year was employed in the UK's horticulture sector. Like thousands of others - from Poland, Romania, Bulgaria, Ukraine and beyond - she left her homeland in order to try and earn a living harvesting British fruit and veg.

She became unemployed after being dismissed - unfairly and without warning, she said - from her job packing tomatoes for a company supplying UK supermarkets. She'd been away and upon her return was told by the agency that employed her that there was no more work available. She managed to find a job picking strawberries at another farm but was sacked, she claimws, after taking time off to attend a union meeting. "I didn't encounter these problems at all in Lithuania in my whole working life", she said.

"In the beginning it was fine... then they brought in a computerised system for weighing the tomatoes... weigh, check, pack, weigh, check pack... we had to do three to four punnets in a minute. If you had three splits [of tomato packaging] in a day you were out. Everything had to look perfect - if not you had a problem."

Irena described how there would be fourteen people in a line, working from crates of tomatoes weighing 15-20 kilogrammes, and that they would not be allowed to talk. Most days she worked between eight and nine hours, with one half hour break; her longest shift was 14 hours. "Line number two, that was known as the line of death", she said. "There was a Lithuanian supervisor and you'd be put with her to be dismissed." Despite being employed at the same packhouse for more than two years, packing thousands of punnets in a day Irena - whose son lives in London; her husband remains overseas - says she was sacked after returning from a trip abroad and being told by the agency employing her that "there's no more work."

She was offered no possibility of recourse with no right of reply or appeal process. She believes that her activities for a trade union played a role in the agency's decision to dismiss her, especially as a number of grievances had recently been made, heightening tensions.

Irena found work at another Kent farm supplying fruit and vegetables to supermarkets but says treatment of the migrant - mostly Polish, Bulgarian and Latvian - workers was even worse. She started work harvesting strawberries but was switched to picking vegetables after developing problems in her fingers. Irena was paid the minimum wage and charged £32 per week for accommodation in a caravan, sharing with four others. She worked six days a week.

She claimed that workers at the farm were sacked daily if supervisors thought they were not productive enough: "The agency would calculate what everyone [in the team] had picked, then the least performer would be sacked", she said. "They'd be eight people in a plastic tunnel when you'd go for a break but by the time you get back four could have been sent back to the caravans if work was not up to scratch."

Additionally, Irena said, workers were expected to walk between different fields - sometimes considerable distances, taking 20 minutes or longer - but the time spent doing so would be unpaid, with the agency deducting the total 'transit' time from wages. "There would be a climate of fear... I was dismissed because I came to a union meeting", she said.

The Joseph Rowntree report makes a number of urgent recommendations for tackling the problem, including strengthening the powers of the Gangmasters Licensing Authority (GLA), the body set up in the wake of the Morecambe Bay tragedy which saw more than twenty Chinese workers drown whilst harvesting cockles in 2004.

Their deaths led directly to the introduction of the Gangmasters Licensing Act, with the GLA tasked with regulating labour providers and 'cleaning up' the food processing, packing, agricultural, horticultural, forestry and shellfish gathering sectors. The GLA aims to ensure workers receive a minimum wage, adequate accommodation, safe transport, contracts and decent working conditions.

Despite a successful track record, there are fears that funding cuts could reduce the GLA's operational ability, with the organisation itself acknowledging that it faces 'a major challenge' to continue its work with the prospect of fewer resources. Commentators have rightly questioned any moves to slim down, rather than beef up, the GLA, particularly now, in light of the evidence presented in the Joseph Rowntree report.

Solutions to this complex problem don't simply lie in enforcement however. Producers could probably learn something about the ethical treatment of workers from the giant G's Marketing in Cambridgshire, which supplies lettuces, beetroots, celery, leeks and onions to Britain's supermarkets. The company has won accolades from within the horticulture sector for its treatment - and unique facilities, including a specially-built hostel with a social centre, sports pitches and a bar - for up to 4,000 migrant workers it employs each year.

When I toured the company's main site at Barway, in Suffolk, last year, I visited migrants at work out on the rigs harvesting lettuces and celery. As I reported at the time, it's dirty, relentless and noisy work - few of us probably realise the sweat that goes into putting that salad on your dinner plate - yet conditions are undoubtably better here than at many other farms.

Retailers could - and should - do much more to ensure their supply chains are 'clean' too. The recently announced government plans for a Groceries Code Adjudicator to 'police' the buying practices of the biggest supermarkets has been broadly - if cautiously - welcomed as a step in the right direction for securing a better deal for supermarket suppliers and their (often seasonal) workers. The challenge now though is to ensure the adjudicator has real teeth and that some of the more far reaching proposals don't get watered down in the face of inevitable lobbying by the corporate food sector.

Inspiration could also come from across the Atlantic and the pioneering work of the US Food Justice certification scheme. The Agricultural Justice Project developed the label in response to the often scandalous conditions experienced by workers on US farms, and is pretty much the first of its kind to specifically focus on the rights and wellbeing of those picking and packing everyday foodstuffs.

Maybe something similar should be considered here in the UK? In the meantime, life for many at the bottom of the food supply chain remains bleak. And the salad remains cheap.

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