Air
There is a widely held belief that air quality in Southland, and particularly Invercargill, is not a problem. Given our relatively windy climate, this assumption is not surprising. However, as we are now learning, the air quality in some of our towns is not always as clean as we might think.
Environment Southland now monitors air quality in Invercargill, Riverton, Gore and Te Anau. Monitoring in Invercargill has been running since 2003 and since then the maximum guideline level has been exceeded a number of times.
What is PM10?
The most widespread air quality problem in New Zealand is contamination by microscopic-sized fine particles. The particles are 10 microns or less in size – about a fifth of the width of a human hair – and are referred to as PM10 (particulate matter 10 microns). Studies have shown that most of the PM10 emitted in New Zealand comes from the burning of wood and coal in domestic solid fuel heating appliances (e.g. open fires, wood and coal burners). Industrial sources of PM10, which are relatively few in number, are regulated in Southland.
Excessive concentrations of PM10 are associated with numerous health problems. These range from minor irritation of the eyes and nose, to more severe effects when inhaled such as respiratory diseases and asthma attacks. Children and the elderly tend to be the most susceptible. These health effects in turn can increase hospital admissions, use of medication, and lost productive days.
Some 30 urban centres throughout New Zealand have been identified as having PM10 levels that periodically exceed the maximum acceptable levels specified by international and New Zealand authorities. This level is specified as a concentration of 50 micrograms of particulate per cubic metre of air (or 50 µg/m3 for short).
Environment Southland monitors PM10 continuously in Gore and Invercargill. We also monitor PM10 in towns throughout Southland.
Air Quality - What are the issues?
- Localised air quality issues associated with odour, dust, smoke, agrichemical spray and other discharges to air from the domestic, transport, commercial, agricultural, horticultural, manufacturing and industrial sectors.
- Ambient air quality issues related to wintertime air pollution in urban areas with its associated health effects and nuisance effects (e.g., reduced visibility, dust or odour nuisance) resulting from burning.
- Global air quality issues connected with the reduction in the ozone layer and with greenhouse gas emissions and consequential global warming.
How air pollution affects the human body
When you breathe in suspended particulate matter (PM10) it can attack and inflame your tissues all the way down the respiratory tract. Because these particles are so small, they can go deep inside your lungs and damage the smallest airways called bronchioles.
Particles may also enter the bloodstream. Together with inflammatory mediators, they cause serious effects on the nervous system, as well as the heart and lungs.
Air pollution has the greatest effect on children, the elderly and those with respiratory and heart problems. Here is what air pollution can do to our health:
- Increase and aggravate asthma
- Create disease in the airways of children
- Increase respiratory illness in children
- Damage the lungs
- Increase deaths from respiratory and cardiovascular disease
- Increase hospital admissions for lung and heart disease
- Cause chest pain and nausea
- Cause shortness of breath and (faster) laboured breathing
- Permanently change lung structure
A burning issue
Prohibited Activities
The National Environmental Standard will prohibit a number of activities that emit hazardous pollutants. Most of the activities specified in the Standard are currently discretionary under Southland's Regional Air Quality Plan, meaning that resource consent is currently required.
Environment Southland is the brand name of Southland Regional Council.