‘Clean’ NZ air

New Zealand has some of the cleanest and safest air on the planet, a new World Health Organisation report suggests. The report analysed data from more than 100 nations, comparing exposure to ambient air pollution and related death and illness. It showed NZ was either in the top five or 10 nations with the best results for concentrations of PM2.5 — a key measure of air pollution. But Associate Professor Simon Hales of Otago University’s Department of Public Health questioned whether the report’s methods accurately reflected rates in smaller countries. “Their estimates of PM2.5 exposure use data from satellites, which are excellent for large countries with little surface air pollution monitoring data, but do not perform so well at local scale in small countries like [NZ].”