Leading Hong Kong clothing manufacturers are coming together to reduce the environmental impact of their factories in response to growing pressure from international retailers. The group, the Sustainable Fashion Business Consortium, is being launched today, World Earth Day. Many Chinese suppliers are being told to clean up operations from their US and European customers. Leading the charge is Wal-Mart. The world's biggest retailer will in October convene a meeting of 1,000 of its suppliers to set goals for reducing their impact on the environment.