There were fresh calls on Thursday for an independent inquiry into Dow Chemical's controversial sponsorship of the London Olympics after Meredith Alexander, a leading environmentalist, resigned from the Games' ethics committee — the Commission for a Sustainable London 2012 — protesting against Dow's links with the 1984 Bhopal gas disaster and accusing the organisers of “toeing” the company's line.

“I feel that the Commission and the London Games organisers are in danger of becoming apologists for Dow Chemicals. They are repeating and falsely legitimising Dow's assertion that they have no responsibility for the Bhopal tragedy,” she told The Hindu, indicating that other members could follow suit.

Terming the deal “ill-judged,” Ms. Alexander said: “I share Amnesty International's view that Olympic bodies are culpable of entering into an ill-judged relationship with Dow, the company that carries the responsibility for the catastrophic gas leak, a responsibility they have repeatedly absconded from.”

She decided to quit after the Commission failed to address the concerns. She felt that continuing to be part of a body that publicly endorsed Dow was “untenable.”

Ms. Alexander, a seasoned campaigner who works for the charity ActionAid, said Dow's involvement had “hurt” the victims' families and “tainted” the Games. “I felt it was absolutely essential for me to stand up and be counted on this.”

She also wanted to highlight the “toxic legacy” of the Bhopal tragedy. “It's one of the worst abuses of human rights in my generation, and I just could not stand idly by.”

The Commission is an official watchdog set up to monitor and ensure that the London Olympics meets its commitment to deliver the most sustainable Games ever.

Besides a £7-million deal under which Dow is funding a fabric wrap for the Olympic stadium in east London, the company has a 10-year sponsorship arrangement with the International Olympic Committee estimated to be worth at least £100 million.

The deal has sparked protests. Noam Chomsky is among high-profile international figures, including British MPs and former Olympians, who have written to Lord Sebastian Coe, Chairman of the London Organising Committee of the Olympic Games (Locog), urging him to scrap the deal. Barry Gardiner, senior Labour MP and chairman of the Labour Friends of India, demanded a parliamentary inquiry.

Dow, which bought the Bhopal plant from Union Carbide after the gas tragedy, denies any liability. The Games' organisers have defended the decision to award the contract to Dow, saying it was taken after all the issues were “very carefully” considered.