Pea-souper smog may be a thing of the past in London, but health experts have warned that air pollution is a major burden on the developing world.

Dr Michal Krzyzanowski of the World Health Organization's Centre for Environment and Health told a conference to commemorate the 50th anniversary of the smog that enveloped London at the beginning of December 1952 that there were “striking similarities between developing countries and London 50 years ago.”

The World Health Report 2002, Reducing Risks, Promoting Healthy Life, looked at the impact of urban …