The report said an 8 per cent nation-wide reduction between 2006 and 2012 resulted in 14 per cent fewer deaths and 15 per cent fewer hospital admissions from man made air pollution. Other reports from the Ministry say that respiratory health is the main effect. These numbers came from a model relating numbers of premature deaths and hospital admissions to measured or estimated concentrations of PM10.
In 2011 Wilton and Familton from Environment Canterbury (ECan) reported to the Conference of the Clean Air Society of Australia and New Zealand on "Health benefits of cleaning up Christchurch's air". ECan air quality scientists have gathered very good records of PM10 concentrations in Christchurch going back for over twenty years. During that time, concentrations have about halved, largely due to the ECan campaign against use of open fires and log burners.