The London 2012 green watchdog remains hopeful it will see a low carbon Olympic flame lit at the opening ceremony of this summer’s Games, despite today releasing a report that raises serious questions about the organisers’ efforts to deliver the “greenest Games ever”.

The Commission for a Sustainable London 2012 has launched its final review before the Games next month, highlighting a range of successes by the Olympic Delivery Authority (ODA) that demonstrate “exemplary” standards for green construction.

However, the report also recorded a series of failures by the ODA’s sister organisation LOCOG, which is accused of missing opportunities to improve its environmental performance in a number of areas, including merchandising and communications.

The report was also critical of the Home Office for insisting every ticket holder should be given a plastic bag for liquids or gels when going through security screening as they enter Olympic venues.

It warned this would give visitors a negative first impression of the sustainability of the event, noting that both LOCOG and the Commission had called on the government to use a more sustainable alternative to plastic bags.

“In the main, the construction site and efforts of the ODA have been fantastic,” Shaun McCarthy, chairman of the Commission for a Sustainable London 2012, told BusinessGreen.

“LOCOG will achieve its goal of delivering the most sustainable Games ever, but frankly the competition isn’t all that great. There are some areas where they could have done better.”

The wide-ranging report highlights the importance of ensuring the Games’ opening ceremony delivers a sustainable message to viewers. McCarthy said he was “reasonably confident” the Olympic cauldron would burn a low carbon flame, even though LOCOG failed on its pledge to use a low carbon flame for the Olympic torch relay. The Commission also do not know what form of technology will be used to achieve this.

The details of the opening ceremony have been kept under wraps, but the report warned against the”propensity” of event producers to use helium-filled balloons, as they would cause litter and damage wildlife when they came back to earth.

The Commission also criticised LOCOG’s reluctance to put pressure on suppliers to deliver more sustainable merchandise for the Games, noting it had been rebuffed at least twice when urging LOCOG to develop greener products.

“We have challenged LOCOG frequently on this issue but to no avail,” the report stated. “We have been advised on more than one occasion that they ‘are not a National Trust gift shop’.”

McCarthy told BusinessGreen that he believed LOCOG was wary of taking risks in stocking merchandise that might not be easily sold, given the expense of the Games.

However, the report said it was reassured by LOCOG’s response after concerns were raised that it had signed a contract with an Arkansas-based printers to produce the Games’ tickets. The 11 million tickets will now be shipped across the Atlantic rather than air-freighted, as previously reported.

But the report did question another area which had been slammed by campaigners – LOCOG’s decision to appoint six sponsors as “sustainability partners”, some of which, such as oil giant BP, have questionable green credentials.

“Although it has delivered additional revenue for LOCOG it is difficult to understand what value this has added in sustainability terms over and above the substantial contribution made by many partners,” said the report.

The report also revealed that just two of the six sustainability partners agreed to participate in the “walk in the park” initiative to promote the sustainable features of the Olympic Park, and it urged future organisers to learn from this mistake by drawing up specific objectives so companies could “earn” rather than buy the title of sustainability partner.

LOCOG’s sustainability partners have been a source of embarrassment for the organisers after Meredith Alexander, a commissioner for the Sustainability Commission quit earlier this year over the Games’ links with Dow Chemical. A hoax website was also recently set up by a green group erroneously claiming BP had been dropped as sustainability partner by LOCOG over its environmental record.

The Games’ travel plans also drew criticism, with the report raising questions about “active and accessible travel”. One unnamed corporate hospitality provider also came under fire for undermining efforts to deliver a “public transport Games”, after signing a private deal with a landowner to provide parking for customers.

The Commission plans to issue two further reports after the Games assessing the sustainabiliy of the event and its legacy on different sectors.

Despite the criticisms, McCarthy maintained that LOCOG and the ODA had made significant achievements in the areas of waste, energy, food and transport, that could pave the way for long-term legacy benefits.

“We’ve for the most part been very impressed by the hard work that’s gone into planning a sustainable Games. What we as a Commission want to see is those plans transferring into practice on the day, because if that doesn’t happen, the ability to call these Games truly sustainable would obviously be in doubt,” he added.

However, Simon Birkett, founder and director of campaign group Clean Air in London, hailed the report as evidence that the London Olympics and government was failing to warn the public about poor air quality episodes.

“This report packs a knockout punch,” he said in a statement. “The most-respected independent organisation associated with the London 2012 Olympics is saying the ‘Emperor has no clothes’.”