Extreme Light Pollution in Australian Cities Poses CVD Risk

Scientists warn light pollution could be damaging your heart

4 July 2024

A two-article series from the Victor Chang Cardiac Research Institute and a number of other prominent Institutes and universities around the world has highlighted the dangers of light pollution on heart health.

With Australians being exposed to almost twice the level of light pollution as people living in the UK and Germany, the Institute’s Director Professor Jason Kovacic says there needs to be more awareness of the health impacts of light pollution and strategies about how to combat it.

Professor Jason Kovacic

The manuscripts, published in the Journal of the American College of Cardiology, focus on global warming, air pollution, exposure to wildfire smoke and toxic chemicals, and the lesser-known drivers of heart disease, including soil, noise, and light pollution.

Exposure to artificial light at night is associated with an increased risk of coronary heart disease and other cardiovascular events, which researchers say is in part related to changes in the body’s circadian rhythm.

Professor Kovacic says: “Most Australians are aware of the most common risks of heart disease such as being overweight, a lack of exercise or smoking, but very few would be aware that light pollution is also adding to this health burden.

“When we are exposed to artificial lights at night, our sleep patterns are disrupted, and it’s easy to see why. Streetlights are left on all night, which can stream in through windows, and far too many of us are on devices until late in the day.

“Every year around 20 million people worldwide die from cardiovascular disease with pollutants, including light pollution, playing an ever-increasing role.”

Professor Kovacic and his fellow authors from the University of Edinburgh, Icahn School of Medicine at Mount Sinai, Global Observatory on Planetary Health Boston College, Centre Scientifique de Monaco, and the University Medical Centre Mainz examined the current evidence on the links between light pollution and heart health. They highlighted one study of 60,000 people that found those with the highest light pollution exposure were 23 percent more likely to be hospitalised for coronary heart disease and 29 percent more likely to die from it.

Professor Kovacic says these findings were especially concerning given the levels of light pollution Australians are exposed to, as demonstrated by the Global Atlas Map on light pollution.

The light pollution map, which uses US Government satellite data and covers every street in the country, reveals that light pollution is a growing problem in every Australian city. Professor Kovacic adds:

“Whilst most of Australia is bathed in darkness at night, our cities have incredibly high levels of exposure. This reflects where most Australians live but it’s interesting to note that our exposure in a country that prides itself on its natural environment has greater light pollution than highly populated countries like Germany and the United Kingdom.”

Country statistics reveal that Australians are also exposed to more light pollution than other G20 countries, including France, Japan, Brazil, Mexico, India, and China. Light pollution exposure has also increased by over a third in Australia since 2012.

Pollutants are known drivers of cardiovascular disease, but they affect the body differently. Smoke and other toxins can be directly inhaled deep into the lower respiratory tract, reach the blood, and then be transported to organs and throughout the body. They can cause oxidative stress, damaging cells and organs, including the heart.

Other pollutants, such as noise and light pollution, can affect sleep patterns, drive inflammation, and lead to an increase in blood pressure and weight gain—key heart disease risk factors.

Note to journalists

The country statistics refer to Rad./1k pop figures—the total light exposure over the country divided by the population. While Australia has many unlit areas, the total light emission each person is exposed to is higher than that of the UK and Germany.

This graph demonstrates how light pollution has been increasing in Australia since 2012.

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For all media enquiries and interview requests, please contact:

Julia Timms
Head, Media & Communications
j.timms@victorchang.edu.au
+61 457 517 355

Acknowledgement of Country

The Victor Chang Cardiac Research Institute acknowledges Traditional Owners of Country throughout Australia and recognises the continuing connection to lands, waters and communities. We pay our respect to Aboriginal and Torres Strait Islander cultures; and to Elders past and present.

Victor Chang Cardiac Research Institute - The Home of Heart Research for 30 Years