Primark has transformed the way that millions of shoppers buy anything from T-shirts to skirts, but its popularity could finally be on the wane, now that the fast-growing discount chain has been voted Britain's least ethical clothing retailer.

An exclusive survey for The Times has shown that the country's “green” consumers believe that, out of all the clothing retailers on the high street, Primark is the worst offender when it comes to failing to address social and environmental issues.

Marks & Spencer, following the continued success of its Plan A initiative, is perceived as leading the way, ahead of George at Asda and Debenhams.

The survey, carried out by Populus, also shows that while the overall rating of every other high street clothing retailer has either gone up or remained steady over the past year, Primark's has fallen.

The findings come four months after a damaging BBC Panorama investigation, which found that some Primark suppliers in India were contracting out embroidery work to firms that used child labour.

The retailer was forced to stop using three suppliers as the adverse publicity threatened to bring its amazing growth story of the past decade to a shuddering halt.

A survey by Drapers, the fashion industry magazine, claimed that as a result of the controversy, 44 per cent of Primark shoppers were likely to switch to another chain.

Primark responded by creating a website to promote its ethical record and vowed to work more closely with non-governmental organisations. The chain, which is part of Associated British Foods, yesterday insisted that its sales had not been affected by any fallout from the Panorama programme.

However, David Lourie, an analyst at Good Business, the ethical consultancy, said that the results of the Populus survey showed that the Panorama investigation had dented Primark's image among consumers.

“This just shows how damaging it can be if you fail to pick up on, or address, social and environmental issues,” he said. “Gap is still pretty far down the list, given the controversy surrounding the supply chain problems it suffered a few years ago.

“The worry for Primark now is that consumers on the high street think: ‘If I cannot trust them during the good times, how can I trust them as we go into a recession?'”

Simon McRae, the senior campaigns officer at War on Want, the anti-poverty charity, went further. “Primark claims to be ethical, but workers producing its clothes face poor wages and conditions,” he said. “It is high time the British Government introduced regulations to stop this.”

The Populus survey has revealed that 45 per cent of concerned consumers claim that their biggest concern when judging a clothing retailer is its treatment of workers in developing countries, ahead of sourcing materials from the UK and a commitment never to use fur.

Quality beats price as the most important factor when it comes to deciding where to buy an item of clothing, reflecting a prevailing feeling on the high street that consumers are beginning to look for overall “value” in the credit crunch rather than simply searching for the cheapest price.

The high rating given to Marks & Spencer has been greatly helped by the wave of publicity from campaigns introduced under Plan A, such as the introduction of a 5p charge to cut the use of plastic bags and a clothes recycling initiative with Oxfam.

Under the scheme, anyone donating an unwanted bundle of clothes, with at least one M&S garment, to the charity shop receives a £5 M&S voucher. The scheme was extended in June after a six-month trial.

Mike Barry, the head of corporate social responsibility at M&S, said that out of the 100 environmental pledges outlined when the high street retailer announced Plan A in January last year, 20 had already been achieved.

He added that the retailer was now pushing ahead in other areas, such as reducing its water usage through a partnership with WWF, formerly the World Wildlife Fund.

He said: “Our customers have been very, very clear. Around 75 per cent have been saying that they expect us to take a lead on these kind of issues. Consumers are just as interested during a credit crunch and will expect us to take even more of a leap on their behalf.”

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