Air quality issues associated with human health risks have been identified in Ranfurly.

Air monitoring carried out by the Otago Regional Council (ORC) last winter has identified high levels of PM2.5 in Ranfurly and other locations.

Particulate matter (PM) is the term for a mixture of solid particles and liquid droplets found in the air, and PM2.5 refers to very fine particles which can be easily inhaled.

ORC air quality scientist Sarah Harrison told the data and information committee earlier this month that elevated levels of PM 2.5 were found in all but one of the 14 ‘airshed’ areas which underwent monitoring.

Health New Zealand says the PM inhalations’ effects can include aggravated asthma, cellular and genetic damage, and respiratory and cardiovascular disease (among other illnesses).

“All airsheds except for Kingston recorded elevated PM2.5 concentrations at night, with a secondary spike in the morning, indicating home heating emission sources,” Sarah said. 

“The PM2.5 concentrations of the airsheds varied; Lake Hāwea, Luggate, Ranfurly and Oamaru had the highest mean concentrations for the monitoring period, and Lake Hāwea recorded the highest 24-hour average PM2.5 concentration of 58 µg/m³.”

It was the first time in many years that some of the locations had been monitored for PM2.5, Sarah said. She recommended additional monitoring and investigations.

The monitoring took place ahead of amendments to the National Environmental Standards for Air Quality (NES) which is being updated to better control the release of fine particles into the air by lowering the PM limit.

ORC general manager policy and science Anita Dawe said most of the PM in Otago towns comes from emissions from home heating. 

When asked about additional monitoring, Anita said it would be considered as part of a review into the ORC Air Plan which is due to start this financial year.

Earlier this month the ORC shared a media release which said the number of air pollution exceedances had fallen this winter, according to a measurement of PM10, a coarser particulate matter less associated with severe health effects.