A FAILURE to adequately regulate or replace wood heaters in Australia despite their major contribution to air pollution is costing lives and money, a growing number of studies suggest.
Research published in the MJA has estimated that in the northern NSW town of Armidale, population 24 504, 14 premature deaths per year are attributable to long term exposure to wood heater pollution, at an estimated financial cost of $32.8 million.
Around 40% of households in Armidale use wood for heating, with each heater linked with $10 930 in health-related financial costs per year, the study estimated.
The study compared fine particulate matter (PM2.5) levels between the winter and summer months to estimate the magnitude of wood heater pollution.
Similar studies have recently found wood heater smoke is linked to premature mortality in Tasmania and Sydney – also showing wood heaters account for more PM2.5 exposure than traffic and power stations in Sydney.
At the time of writing, the Andrews government in Victoria announced it would begin providing $1000 rebates to support low income households to replace their old heaters with energy-efficient reverse cycle systems.
Lead author of the Armidale study, Dr Dorothy Robinson, a statistician and Armidale councillor, welcomed the announcement and said similar schemes were needed throughout Australia.
“Helping low income households enjoy affordable, energy-efficient heating is a win for health and a win for the environment,” she told InSight+.
“Providing every wood heater owner in Armidale with funds to replace heating and upgrade insulation would take a modest amount of funding compared with the estimated cost of the lost years of life of $10 930 per heater per year.”
She cited evidence from the successful Launceston Wood Heater Replacement Program in Tasmania from 2001 to 2004. Funded by the Howard government at a cost of $2.05 million (approximately $29 per resident), the scheme saw the prevalence of wood heaters in Launceston fall from 66% to 30% of all households.
Improvements in air quality as a result of the Launceston scheme were linked with reduced annual mortality in males and reduced cardiovascular and respiratory mortality during winter months, according to a study in the BMJ. However, progress stalled once the subsidies ceased and residents installed new wood heaters.
Professor Fay Johnston, a public health specialist and author on both the Armidale and Launceston studies, told InSight+:
“We really need concerted federal, state and local government support to reduce wood heater pollution.
“There is no evidence that Australia’s main strategies of ‘public education on heater operation’ or gradual tightening of wood heater emission standards, has improved community-level air quality anywhere.
“The only interventions with good evidence for improving the air are those that reduce wood heater numbers.”
It was not a message everyone was happy to hear, Professor Johnston acknowledged.
“Wood heaters are so lovely and appreciated for their attributes – it’s hard to face the harms that go with them,” she said.
However, Professor Johnston said the tide of public opinion appeared to be turning.
A 2020 nationally representative survey by Asthma Australia of 25 000 people found 77% agreed that woodfire heaters should not be allowed in urban or built-up areas, and over half agreed they should be phased out or banned completely.
Professor Johnston said she was not in favour of banning wood heaters or their sales.
“There’s still a place for them on bush blocks in rural and remote areas,” she said. “But they shouldn’t be used in populated areas, especially in places like valleys where air pollution pools.”
Real-world burn conditions were very different from the efficient burn conditions in laboratories where standards were assessed, she noted.
A New Zealand study found that in real-world conditions, modern heaters far exceeded the emissions standards to which they had been built.
Failings in the regulation of the wood heater sector were detailed in a 2013 federal inquiry into the health impacts of air quality. Efforts to revise the standard for wood heaters began in 2003 but broke down when consensus could not be reached between industry and other stakeholders, the inquiry’s final report noted.
Professor Christine Jenkins, chair of the Lung Foundation Australia said there was “a substantial body of evidence for the adverse effects of woodfire smoke on respiratory, cardiovascular and all-cause mortality globally”.
“PM2.5 particles are pro-inflammatory and cause coronary and respiratory inflammation,” she said. “Acute ischaemic events occur more often on high PM2.5 days.
“Larger particles cause airway irritation, mucus secretion and nasal and conjunctival inflammation,” she added.
Dr James Markos, a respiratory physician in Launceston said he had met hundreds of people affected by wood smoke.
“I have seen many people end up in hospital with asthma attacks from it and many more who are affected and who have to use much more medication to treat symptoms and avoid hospital,” Dr Markos said.
Dr Markos said there was no safe level of wood smoke exposure.
“It is identical to the risk of lung cancer from passive smoking,” he said. “So, if you live in a smoky hollow, you are playing Russian roulette with whether you might end up with lung cancer after 20 or more years.”
Professor Michael Abramson, Professor of Clinical Epidemiology at Monash University said there was “a strong case for public money to be spent on replacing old inefficient wood heaters, preferably with modern electric heating, such as reverse cycle air conditioning”.
A spokesperson for the federal Department of Agriculture, Water and the Environment said there had been a downward trend in wood heater emissions since the early 1990s, based on data from the Australian Greenhouse Emissions Information System.
“Under the National Clean Air Agreement, Australia’s environment ministers have committed to reducing emissions from wood heaters,” the spokesperson said.
“Most states and territories have adopted new wood heater emissions and efficiency standards and have published best-practice guidance for using wood heaters.”
Also online first at the MJA
Podcast: Dr Dorothy Robinson, Adjunct Senior Research Fellow at the University of New England in Armidale … FREE ACCESS permanently.