Cape Town - An international conference on air pollution opened in Cape Town on Monday with a call on South African industry to show leadership and comply with emission standards.Delegates at the 16th International Union of Air Pollution Prevention and Environmental Protection Associations (IUAPPA) congress heard mostly poor South Africans were exposed to pollutants."The people that are exposed to the smog are almost always the people that cannot afford to pay the doctors' bills for bronchitis, asthma or, worse, lung cancer," Environmental Affairs Minister Edna Molewa said in a speech delivered on her behalf by senior department official Judy Beaumont.Reducing air pollutants and greenhouse gas emissions could be achieved by changing the way business was conducted, she said."One of the greatest opportunities we foresee is the leadership role of industry in setting clear plans for the introduction of the necessary technologies, to ensure that they are able to meet economic targets and be within the minimum emission standards."DeathsBy so doing they were ensuring that the air people breathed was not harmful to their health.Molewa said she recognised this presented problems of technology and finance."I call upon industry to respond to this challenge constructively."The minister also cited UN Environment Programme figures, which linked air pollution in urban areas to "up to two million premature deaths world-wide each year, and is estimated to cost [about] two percent of GDP in developed countries, and five percent in developing countries".The theme of this year's conference is "Many Nations - One Atmosphere: Plotting the Path to Sustainability".Specific topics set for its five-day programme include air quality in the developing world; air pollution and climate change; bio-diversity, eco-system services and crop damage; and, international co-operation on air pollution.Speaking at the opening, IUAPPA chair Richard Mills said the fact that SA contained elements of both a developing and developed country made it a good venue for the conference."South Africa is in many ways at the epicentre of the climate and clean air issues. The impact of these problems on the country is visible and substantial, and that is a critical starting point," he said.It is the second time the conference has been held in SA. The 11th international meeting was in Durban in 1998.