Timaru one of country’s most polluted spots, figures show
Timaru’s air pollution continues to be a problem, ranking amongst the worst in the country. (File photo)
Preliminary data shows Timaru is the third worst location in the country for particulate matter in the four-year period from 2017 to 2020.
The Ministry for the Environment and Statistics NZ’s Our air 2021 report, released on Thursday and is part of the ministry’s environmental reporting series.
The report covers five different air pollution measurements used throughout the country, evaluating them against two sets of guidelines – one national, the other international.
Timaru features in the particulate matter section of the report – PM10, larger particles (but still small enough that they can be inhaled) and PM2.5, finer particles, generally 2.5 micrometres or less in diameter.
Particulate matter refers to a mixture of solid particles and liquid droplets found in the air and are considered to ‘’cause the most significant human health impacts from poor air quality”.
The particles are so small that they can get into the lungs, potentially causing serious health problems.
Timaru’s air quality consistently ranks among the worst in the country, at one point peaking as one of the worst in Australasia.
For the larger particulate measure of PM10, Arrowtown exceeded the New Zealand PM10 standards the most, with an average of 30 days per year, from 2017-2020.
While Timaru’s Anzac Sq and Pomona St, Invercargill, both exceeded the standards on an average of 12 days a year, over the same four year period.
The same three sites exceeded the annual average PM10 World Health Organisation (WHO) guidelines at least once a year.
Anzac Sq, Timaru, had the most exceedances over this period, exceeding the guideline in 2017, 2019, and 2020.
On the smaller PM2.5 measure, Timaru’s Anzac Sq was the third worst, measuring 31 average daily breaches of the WHO 24-hour average guideline per year, behind Masterton East’s 36 days, and Blenheim Bowling Club’s 52 days.
In terms of long-term exposure, Geraldine and Timaru joined five other sites nationwide that recorded at least one breach of the annual mean PM2.5 WHO guideline for air quality from 2017-2020.
The other sites were the Blenheim Bowling Club, Kaiapoi, Masterton East, Masterton West and Rotorua.
Nationwide in 2019 the residential sector contributed 30 per cent of PM2.5 emissions, primarily burning wood for home heating, while dust from unsealed roads was the dominant source of PM10, the report says.
It also notes WHO updated its global air quality guidelines this year for the first time in 16 years, making them more stringent.
But the changes…