Some western Sydney suburbs with booming populations are among the least healthy places to live in the city, new maps showing environmental hazards and havens have revealed.
The Blacktown City Council suburbs of Bidwill, Hebersham and Emerton scored 56.5 out of 100 in Monash University’s latest environmental health quality index (EQHI) – the lowest scores in metropolitan Sydney.
GP Dr Kim Loo hands every patient a flyer telling them how to keep cool in western Sydney’s heat.Credit: Dion Georgopoulos
Higher scores in the index indicate a favourable local environment and health conditions, while lower scores indicate a greater risk of premature death.
It’s a concerning result for Blacktown, where suburbs dominated the lower end of scores. It is expected to gain more than 120,905 people by 2041 – the largest increase of any council area in the state.
Meanwhile, less than an hour’s drive from Bidwill is Bayview, which boasts a near-perfect score (99.6), along with a string of other northern beaches areas, including Terrey Hills and Duffys Forest (98.9), and Avalon and Palm Beach (95.8).
The map of Sydney’s steady gradient highlights the yawning divide between the affluent east and disadvantaged communities in the west.
Researchers combined death and socioeconomic data, and 11 environmental factors, including mean temperatures, green space, building density and air quality between 2016 and 2019, calculating an overall score between zero and 100 for 2180 Australian suburbs and regions.
Socioeconomic status was the most influential factor, followed by air pollution and heat.
Researchers hope their model will help guide policymakers seeking to combat environmental risks by planting more trees and introducing public transport options.
It could also be used by families deciding where to relocate: real estate agents could spruik favourable EQHI scores alongside sought-after school zones.
“We are all constantly exposed to environmental factors - the air we breathe, heat, humidity and contact with green spaces – but we don’t understand the combined effect of our environment on our mortality risk,” said senior author and Monash professor of global environmental health Yuming Guo.
The researchers had hoped to include nitrogen oxide (air pollution from burning fossil fuels), walkability and noise, but there was a lack of sufficient data. Future updates could include the risk of flooding and cyclones, mental health, and renal and bone disease, Guo said.
Associate Professor Nicholas Osborne from the University of Queensland’s school of public health said health was “a mosaic of genes, behaviours and environment” and was “difficult to unpick”.
“Is it the people or their environment or a complex interaction?” Osborne said. “Is it all just a proxy for socioeconomic status?”
UNSW City Futures Research Centre professor Susan Thompson said socioeconomic status can be absolutely defining.
“It can determine the environment you can afford to live in, and higher-quality environments will inevitably be more expensive,” Thompson said.
Guo said money did not tell the whole story. Environmental factors played a role, especially in areas with “economic disparities”, the researchers reported in the journal Environment International.
In other words, wealthy people in lower socioeconomic areas are still exposed to detrimental health effects of their environment, just as disadvantaged people living in wealthier suburbs are likely to feel the benefits.
Sydney’s ‘heat island’
GP Kim Loo’s car dashboard read 38 degrees on Tuesday afternoon as she drove through Blacktown. In Bayview, the temperature was 28 degrees.
At her medical practice on a busy road in Riverstone (EQHI 65.6), Loo handed every patient a flyer with practical ways to stay cool: submerge your feet in water, wear wet clothing, use ice towels and drink cold water.
Loo cares for western Sydney and Hills Shire patients with high rates of socioeconomic disadvantage, diabetes and obesity, poor health literacy and English proficiency. She also cares for their wealthy neighbours.
“A lot of my patients have fans, and some have air conditioners, but with the cost-of-living crisis, a lot of them are very cautious about turning them on,” Loo said.
“My patients who work outside – roofers, scaffolders – start work at 4am because it’s too hot during the day.
“My patients who are living in domestic violence [households] … I worry about them when they can’t keep their houses adequately cooled at night,” she said.
One 72-year-old patient working in his son’s shed on a 38-degree day collapsed and went into renal failure.
EQHI’s environmental and socioeconomic factors
- Socioeconomic status (the Index of Relative Socio-Economic Advantage and Disadvantage)
- Fine particulate matter (PM2.5)
- Ozone (O3 )
- Green space: Normalised Difference Vegetation Index
- Night-time light
- Mean summer temperature
- Mean winter temperature
- Summer temperature variability
- Winter temperature variability
- Relative humidity
- Building density
- Road density
Western Sydney Regional Organisation of Councils (WSROC) runs a heat resilience program that contributes to the Greater Sydney Heat Smart City Plan and funds community flyers in 10 languages with tips on how to heat-proof a home and keep the elderly and children safe during heatwaves.
WSROC president and Blacktown Mayor Brad Bunting said rapid housing development combined with geographic conditions could produce summer temperatures 10 to 15 degrees higher than in coastal suburbs – a phenomenon dubbed the “urban heat island effect”.
Google Maps satellite images of newer suburbs Stanhope Gardens and Marsden Park show seas of black roofs that can raise temperatures by as much as 10 degrees on a hot day.
“You’ve got houses packed together with barely any yards, black roads and black roofs because black tiles were cheaper,” Loo said.
George Institute global program for universal health coverage lead Dr Laura Downey said the EQHI was “incredibly useful for theoretical purposes” but should be interpreted with caution.
The results “could mask important details of ‘who’ is dying because of the quality of their environment,” Downey warned.
And, by focusing on mortality data, the EQHI did not consider the effects of environmental factors on quality of life, miscarriage and stillbirth, how they interplayed with sex and gender, or the disproportionately higher burden of disease among Aboriginal and Torres Strait Islanders, she said.
with Liam Mannix
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