The report, called 'How Green is Your Supermarket', was compiled by Liberal Democrat MP Norman Baker and focuses on the nine leading UK supermarkets - Tesco, Asda, Sainsbury, Safeway, Morrisons, Somerfield, Co-op, Marks & Spencer and Waitrose.
Using data supplied by the supermarkets themselves, Baker's report sought to establish just how much waste and pollution were being generated by the food retail sector, to what extent local sourcing was being used and how much energy was being consumed.
From the air pollution caused by shoppers taking their cars to the out-of-town store locations to the energy consumed by the growing number of outlets, some of which are now open 24 hours a day, the impact of the food retail sector on the environment is significant.
Take plastic carrier bags, for example. One unnamed retail chain distributed a whopping nine billion bags last year according to the report, more than all the others put together. Half the chains already offer some form of biodegradable bag and all of them offer reusable bags, but more still needs to be done to cut the number of bags in circulation, Baker's report suggests.
Encouragingly, most stores were open to some form of plastic bag tax, but not in the same way as that currently in place in Ireland, where customers are charged €0.15 per bag and where plastic bag consumption has dropped 90 per cent as a result. But according to UK retailers, such a system would mean that fewer carrier bags would be used for rubbish collection, in turn increasing sales of bin liners and paper carrier bags, both of which use more energy to produce and transport.
Some stores are already doing more to tackle the plastic bag problem. The Co-op, traditionally the UK's most environmentally and ethically aware supermarket group, was the first to provide biodegradable bags, and now provides them in 10 per cent of its stores, while Somerfield offers them in all of its outlets. Tesco recently decided to roll out a new biodegradable bag which breaks down within just two years.
The report also shows that the average UK household spends £470 a year on packaging - one-sixth of its total food budget - and this also contributes to the growing levels of waste generated by the retail trade.
Under EU law, all the retailers have to recycle at least 19 per cent of the paper and cardboard they use, but most go much further than this. Waitrose, for example, recycled up to 95 per cent of its cardboard packaging, and the others recycled between 70 per cent and 93 per cent on average.
Again, the Co-op was ahead of the pack, using recycled cardboard and plastic from its stores for the packaging of its own brand products, and is one of the few chains not to use polystyrene trays for the majority of its fresh produce trays. Tesco introduced reusable plastic trays for its fresh produce in 2000.
Retailers are frequently accused of not doing enough to support local producers and suppliers, shopping around for the cheapest supplier in a bid to boost their margins. The Baker report supported these criticisms, showing that just 1-2 per cent of supermarkets' turnover comes from local food providers. This is not only detrimental to the livelihood of Britain's farming community but also has serious implications on the environment - food which has to travel further uses more fuel and causes more pollution.
Co-op, once again, was the notable exception to this, with some 55 per cent of its produce sourced within a 30 mile radius of the store. Waitrose also has a scheme designed to increase local sourcing, while Asda is also a strong supporter of local goods.
With stores now bigger than ever and the liberalisation of opening hours allowing some to stay open all day if they want, energy consumption by the supermarket chains has increased substantially. Some are decidedly more efficient than others - the lowest energy use per store figure was 0.5 Gigawatt hours, while the greatest was 6.4Gwh, nearly twice the sector average. Some chains have set targets for the use of renewable energy - M&S, for example, will take 10 per cent of its energy from renewable sources from next month, while Sainsbury's use of renewable power meant that it is on track to reduce carbon dioxide emissions by 10 per cent by the end of next year.
But emissions are still a major cause for concern when it comes to distributing goods. Just three of the chains used rail to transport products (a reflection of the parlous state of the UK rail network as much as anything else), while some lorries were running at just 60 per cent capacity.
Half of the retailers questioned said they had green travel plans in place at head office and were feeding them out to individual stores, while half also said that they used biodiesel or other alternative fuels - although only for around 11 per cent of their fleet.
Safeway was the market leader in this regard, while Asda was ahead of the rest in shifting more of its distribution to the rail network.
While Baker was broadly supportive of the moves already underway by many retailers to reduce the impact of their business on the environment, he nonetheless called for more action from both the retailers themselves and from government. In particular, he called for a more in-depth investigation of the impact of plastic bag use and a possible change to the recycling legislation to reduce the use of cardboard packaging.
He also called for better reporting of recycling rates from the supermarkets, a commitment to reduce lorry mileage and a pledge to source more products from local suppliers.
The full report, including all 24 recommendations, can be read here.