Madonna has vowed to commit to an eco-friendly regime - after facing criticism over her "unethical" business interests. The Hung Up star was rebuked for her 'environmentally unaware' investments in oil companies and the "10th all-time most toxic company", aluminium producer Alcoa. But Madonna insists, following her involvement with Saturday's (07Jul07) Live Earth event, she has been forced to re-evaluate her stance on climate change. Her spokesperson says, "Madonna's agreement to sing at the Live Earth event is merely one of the first steps in her commitment to being environmentally responsible. "She is educating herself and her family and has begun to make changes around her that reflect her awareness and concern for the future of the planet."