As world leaders meet in Glasgow at COP26 to curb emissions of greenhouse gases and combat climate change, a new study finds that the world’s top economies and their consumption habits are responsible for half the global deaths from noxious particle pollution. Most of these deaths are occurring in developing countries laying bare stark environmental inequities.

Particle pollution, which is dangerous when inhaled, is different from the greenhouse gases which are heating the planet, but is also a byproduct of fossil fuel burning.

Each year, around four million people die prematurely from particle pollution. The study suggests that two million of those deaths are tied to goods sent to and then consumed by the world’s major economies, or members of the Group of 20 (G-20). One premature death was estimated to occur from the lifetime consumption of every 28 people living in a G-20 country.

The G-20 member countries make up nearly two-thirds of the global population, 80% of the world’s economic output and three-quarters of international trade. They also have large environmental footprints in consumer products purchased and used, with mostly developing countries producing the goods and incurring much of the consumer-related health damage.

“Most of the people [are] now getting to understand, OK, a lot of consumption [produces] greenhouse gas,” said Keisuke Nansai, lead author of the study. “This paper says, OK, a lot of consumption also leads to four million deaths in the world due to [particulate air pollution]. But the G-20 has two million deaths’ responsibility.”

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Nansai and his colleagues evaluated countries’ environmental footprints using a consumer-based approach, allocating emissions along the supply chain for a product and its final place of consumption. For example, a shirt bought in the U.S. has an emission footprint across several countries. The cotton could be produced in India and sent to China for manufacturing. Power to create the clothes may come from oil perhaps from Saudi Arabia.

Along the production route, harmful pollutants can be released into the atmosphere. The researchers specifically looked at deaths attributed to particulate matter less than 2.5 microns, called PM2.5. These tiny pollutants can travel to the lungs and cause health problems from respiratory illnesses to heart disease to lung cancer.

“My calculation is that all of the premature deaths due to PM2.5 during the supply chain should be attributed to the consumer,” said Nansai. “At a business level, we have a potential to switch our view from the concept from the production-based to the consumption-based footprint thinking.”

The team mapped PM2.5 concentrations and estimated the health impacts from the particulate exposure in 199 countries and regions. Then they linked the information to the trade and consumption of goods in 19 of the G-20 countries (excluding the European Union since they are not entitled to presidency of the group).

They found about 1.98 million premature deaths occurred worldwide at an average age of 67 years. About 78,600 deaths occurred in infants below 6 years old.

More so, 11 of the selected top economies caused more than 50% of premature deaths in other countries. Most of the major economies had large footprints in China and India, which also had the largest total number of premature deaths.


In the U.S., around 62% of the deaths tied to its consumer footprints occurred outside of the country, with significant impacts in China, India, Mexico, Russia, Bangladesh and the Philippines. Canada’s footprint showed 85% of premature PM2.5-related deaths occurred outside of the country.

The study used data from 2010 due to data availability, but Nansai says the results are still relevant today. In countries such as China, India and Nepal, air quality may have slightly improved in recent years but the health risks due to PM2.5 haven’t changed much, he said.

“In terms of health risk of PM2.5, the relationship between the air [pollutant] concentration and the risk is not linear,” said Nansai. “Even though the concentration becomes better, this doesn’t change, so there is a need to improve air quality much, much more.”

World leaders are currently meeting at the United Nation’s COP26 conference in Glasgow to negotiate how to curb greenhouse gas emissions among other environmental pledges. But those negotiations will likely not directly address these consumer-based footprints, primarily because nations are addressing their own emissions produced within their country.

“Unfortunately, still at the government level, each nation [is] still focusing on the domestic issues. That’s a big gap,” said Nansai. “A discussion at COP26 of carbon footprint neutrality rather than direct national emissions would help solve the twin problems of climate and human health.”

Perhaps more helpful, Nansai said, is discussing these issues at the summit meetings attended by the responsible G-20 nations. The 2021 G-20 summit, which took place on Saturday and Sunday, addressed several international issues. Leaders agreed to halt publicly financing coal-fired plants abroad by the end of the year. They also recognized the need to hit net-zero emissions by the mid-century and to provide $100 billion each year to poorer countries more susceptible to climate change.


“G-20 is not representative of all the nations,” said Nansai. “But G-20 has a chance and the platform to start to negotiate a discussion to solve this problem.”

During the meeting, the White House also released plans to promote better international cooperation for near-term supply chain disruptions and expand the supply chain process in the long term, including addressing components such as raw materials, manufacturing, shipping, logistics, warehousing and distribution.

Companies have also taken steps to reduce their environmental impact of consumer goods. Many companies, such as Apple, Microsoft, and Toyota, disclose the amount of greenhouse gas emissions and water use involved in their products, not the amount of associated air pollution.

“Without the international collaboration, this situation will continue,” said Nansai. “My message to all stakeholders, including the national government and also companies, should watch their supply chain environmental impact.”