Madonna at the Live Earth concert. (AFP)

London, July 8: She provided the finale to yesterday’s Live Earth concerts, even writing a special song to mark the worldwide musical event.

But instead of being lionised, Madonna found herself accused of hypocrisy last night after allegations that she has financial links to some of the world’s biggest polluters.

The Ray of Light Foundation, a charitable fund established by the star to support her favourite causes and named after one of her biggest selling hits, has $4.2 million of shares in a string of companies including Alcoa, the American aluminium giant, the Ford Motor Company and Weyerhaeuser, an international forest products company. All have been criticised by environmentalists.

Alcoa was ranked number nine on a list of all-time toxic companies drawn up by the University of Massachusetts’ political research institute in 2002. Other companies linked to the foundation, including Northrop Grumman, the global defence and technology giant, and Kimberly-Clark, the huge health group, appear on the same list.

The disclosure was made by America’s Fox News network, which obtained the foundation’s most recent tax returns for 2005.

News of Madonna’s links to the companies are an embarrassment to Live Earth’s organisers, who were also forced to defend themselves yesterday against accusations that they had overstated the extent to which man has contributed towards climate change and that the organisation of the Wembley Stadium event was flawed.

Defending Madonna, Kevin Wall, the founder of Live Earth, said yesterday: “I didn’t see the Fox News report but Madonna is here today, which shows her commitment.

“Today we’re not focusing on what she or any of the artists may have done in their past; it is about the future. Whatever is being said, I know that her commitment to this cause runs deep. She is performing for free and has written a new song for us, which I think goes to show that.”

Last night Madonna, 48, brought to a close the last of eight concerts on seven continents, which began in Antarctica early yesterday morning. As well as performing the specially written Hey You, she sang three of her biggest hits: Hung Up, La Isla Bonita and, paradoxically, Ray of Light. She declined to comment on the Fox News report.

Earlier, music stars including Genesis, Snow Patrol and Razorlight performed to a crowd of 65,000 people. Many admitted that they had attended for the music, not the cause.