A commissioner of the watchdog established to monitor the sustainability of the London 2012 Games has resigned over the issue of Dow Chemical's sponsorship of the Olympic Stadium wrap…Campaigners have called on London 2012 organisers to drop the £7m sponsorship deal, claiming the company has outstanding liabilities relating to the 1984 Bhopal disaster…Dow has consistently claimed that it has settled all liabilities relating to the disaster following its acquisition of Union Carbide [part of Dow], the owner of the plant at the time of the incident, which led to the deaths of up to 20,000 people and serious injuries for tens of thousands more.