In many higher-income countries, air pollution is a social justice issue too, with the poorest and those from ethnic minority backgrounds least likely to own a car, but worst affected by dirty air. According to the World Health Organization, air pollution is a public health emergency - 99 per cent of the global population breathe toxic air. Rosamund and I first collaborated to help get air pollution recognised as a cause of death on Ella's death certificate, a first in the UK. [Extracted from the article]