Pollution from G20 consumption kills 2 million people a year

3 November 2021
Japanese-Australian study reveals deaths caused by consumption
Monitoring pollution at production sites is fairly straightforward. Now Professor Manfred Lenzen and Dr Keisuke Nansai have tracked deadly pollution caused by consumption in rich countries, raising questions about who is responsible.
Haze pollution over Istanbul. Particulate matter caused at the end of consumption supply chains has been tracked by a joint Japan-Australia research team. Photo: Shutterstock

Haze pollution over Istanbul. Particulate matter at the end of consumption supply chains has been tracked by a joint Japan-Australia research team. Photo: Shutterstock

The haze that blurs a blue sky or a beautiful skyline is caused by tiny particles called PM2.5, particulate matter less than 2.5 microns wide, about 30 times smaller than the width of a human hair. Despite their microscopic size, global PM2.5 is responsible for more than 4 million premature deaths a year.

Now, a new study shows that half of those deaths are caused by consumption-induced pollution from the world’s 20 biggest economies.

Their very small size is what makes PM2.5 matter so dangerous. The matter can be produced in manufacturing, fuel combustion or from vehicle exhaust. Easily inhalable, it can accumulate inside the lungs, where it can dramatically increase the risk of cancer and other deadly diseases. While this pollution spreads throughout the atmosphere, it is the poor that are especially vulnerable to these tiny particles, causing widespread premature death.

Lead author Dr Keisuke Nansai said: “Most deaths are in developing countries, and without international coordination the situation will worsen.”

Dr Nansai is Research Director at the Material Flow Innovation Research Program of the National Institute for Environmental Studies in Japan. He conducted much of the study as a Visiting Professor at the Centre for Integrated Sustainability Analysis (ISA) in the School of Physics at the University of Sydney. 

The research is published today in Nature Communications.

While most countries acknowledge they contribute to PM2.5 levels, there is little agreement on how much and therefore who is financially responsibile. While direct measurement of PM2.5 production from factories and cars is reasonably straightforward, it is much harder to determine how much of this pollution is caused by consumption.

This is a vital question to answer, Dr Nansai said, who tackled the problem while working with Professor Manfred Lenzen at the University of Sydney.

Unlike direct production, which first affects the producing nation and then spreads across borders, PM2.5 pollution caused by consumption may originate in distant nations and have negligible effects on the consuming nation.

Dr Keisuke Nansai was a Visiting Professor in the School of Physics.

Dr Keisuke Nansai was a Visiting Professor in the School of Physics. 

Dr Nansai said: “Pollution in the form of production emissions creates a motive to implement joint PM2.5 reduction measures in neighbouring countries. Such cooperation is unlikely among countries that are geographically distinct.”

G20 members make up more than three quarters of international trade and world economic output. Therefore, Dr Nansai and his colleagues reasoned that an understanding of the impact that consumption in these nations has on PM2.5 levels would provide a reliable benchmark.

Using Eora, a database developed at the Centre for Integrated Sustainability Analysis, to measure global supply chains around the world, the study mapped out the emissions made by consumption alone.

The study shows that consumption in the world’s biggest economies, such as the US and UK, causes a significant number of premature deaths in faraway nations, such as China and India, whereas the premature deaths caused by production are more common in neighbouring nations.

Professor Manfred Lenzen.

Professor Manfred Lenzen.

Professor Lenzen said: “This research shows that buying products sometimes means putting lives at risk. While we know that our carbon footprint jeopardises our grandchildren’s livelihoods, this research shows how our consumption harms other people’s health in a much more immediate and direct way.”

COVID-19 is a respiratory disease that is most lethal to the elderly. Similarly, the premature victims of PM2.5 are also mostly elderly. However, unlike COVID-19, the study found another group susceptible to the PM2.5 produced by consumption.

“We found that the consumption of G20 nations was responsible for 78,000 premature deaths of infants [up to 5 years old] worldwide,” Dr Nansai said. This impact was felt hardest in poorer nations.

Dr Nansai and his colleagues stress that if consumption is not considered, then most countries will not think they should pay any penalty for these deaths.

“As long as responsibility for infant deaths due to production emissions is the only issue pursued, we can find no rationale for nations to confront the mass death of infants [in faraway nations],” they write in the study.


This research was supported in part by a Grant-in-Aid for Research from the Japanese Ministry of Education, Culture, Sports, Science and Technology, and by a Fund for the Promotion of Joint International Research of the Japan Society for the Promotion of Science.

Dr Keisuke Nansai

Lead author, National Institute for Environmental Studies in Japan

Professor Manfred Lenzen

Co-author, Centre for Integrated Sustainability Analysis, School of Physics, University of Sydney

Related articles