How can a charity-supported t-shirt come from a dismal factory where staff are abused and do grueling work for low wages?

The Spice Girls and Comic Relief said they checked Ethical Sourcing criteria for Represent, the online retailer who made the t-shirts that sparked an uproar, but subsequently switched manufacturers without their knowledge. One representative stated that he assumed "full responsibility" for the problems identified by a Guardian Survey this week.

But it is not surprising that the workers of the bangladesh The factory where t-shirts were made was paid less than the living wage.

Countries such as Bangladesh are popular places to operate because they offer cheap workmanship alongside the expertise in the clothing industry.

The legitimate minimum wage 8,000 taka (£ 73.85) a month for garment workers in the country, slightly less than the amount received by the workers with whom the Guardian spoke.

The amount was increased by 2,700Tk per month in December, but activists say workers need 16,000Tk to live comfortably in Bangladesh. With such low wages, employees often feel obliged to work many extra hours to make ends meet.

Beyond wages, verification terms in clothing supply chains requires considerable resources, covering a complex network of yarn and fabric manufacturers, end-of-life services and tailoring, all located in developing, remote and mediocre with poor communication infrastructure.

Local laws may regulate fire safety, remuneration and working conditions, but their application is often insufficient because inspectors are inadequate and the potential for corruption of public servants is high. At the same time, workers may find it difficult to raise awareness of the problems resulting from weak union recognition and fear of reprisals.

After the Rana Plaza clothing factory collapse In Bangladesh, where more than 1,000 workers have died, dozens of retailers and brands have signed the agreement on fire safety and building safety. he funded inspections and improving buildings, including fire doors and framing, as well as informing workers about their rights and training managers in the detection and resolution of problems.

Mary Creagh, chair of the UK Parliament's Environmental Audit Committee, who conducted a sustainable fashion survey, previously said: "The best audit [of conditions] … is taken by the workers through their elected representatives in your factories. "Globally, less than 10% of garment industry workers are unionized," she added.

However, measures taken to increase union representation in Bangladesh and other supplier countries have been slow, with union leaders and members being intimidated as business owners and some governments view activists as a threat.

Where local regulation and union representation are weak, retailers have always tried to eliminate poor factories by conducting regular inspections by their own staff or by professional ethical auditors.

Sedex, which has 50,000 members in more than 150 countries, allows brands to share ethical standards data in thousands of factories around the world.

But Peter McAllister, Executive Director of the Ethical Trading Initiative, which brings together companies, unions and campaign groups to try to improve the manufacturing conditions of the garment, said retailers and brands could not rely solely on inspection reports. deliberately ignorant ".

The best retailers have field teams that work closely with suppliers to monitor conditions and verify details of plant capacity and the time required to complete specific work projects.

Such a detailed survey can then identify unrealistic prices – prices that may induce plant owners to reduce costs by forcing their staff to work unpaid overtime or outsource work to less reputable institutions that do not may not have been inspected.

McAllister said the price was one of the best indicators of working conditions: "If something is very cheap, you have to ask yourself if it is really possible to do it in a properly managed factory, with a living wage. "