Environmental pollution — from filthy air to contaminated water — is killing more people every year than all war and violence in the world. More than smoking, hunger or natural disasters. More than AIDS, tuberculosis and malaria combined.

Key points: One out of every six premature deaths in 2015, about 9 million, was due to toxic exposure

One out of every six premature deaths in 2015, about 9 million, was due to toxic exposure The financial cost of pollution-related death, sickness and welfare is $5.9 trillion annually

The financial cost of pollution-related death, sickness and welfare is $5.9 trillion annually The worst affected countries are in Asia and Africa, with India topping the list

One out of every six premature deaths in the world in 2015 — about 9 million — could be attributed to disease from toxic exposure, according to a major study released on Thursday in The Lancet medical journal.

The financial cost from pollution-related death, sickness and welfare is equally massive, the report said, costing some $5.9 trillion in annual losses, or about 6.2 per cent of the global economy.

"There's been a lot of study of pollution, but it's never received the resources or level of attention as, say, AIDS or climate change," Dean of global health at the Icahn School of Medicine at Mount Sinai, New York, and the lead author on the report, Philip Landrigan said.

The report marks the first attempt to pull together data on disease and death caused by all forms of pollution combined.

"Pollution is a massive problem that people aren't seeing because they're looking at scattered bits of it," Mr Landrigan said.

And Australians are not immune, according to University of Queensland researcher Professor Peter Sly.

He said while pollution was not widely recognised as a health problem in Australia, there is a body of research which suggests that it is.

"There are peer-reviewed studies which show that exposure to pollutants causes higher levels of respiratory illnesses and impacts foetal growth," he said.

"While we are not Beijing or Delhi, we can still measure and demonstrate health impacts of pollution on the Australian population, and water contamination from firefighting foam is just one recent example."

Africa, Asia worst affected

Experts say the 9 million premature deaths the study found was just a partial estimate, and the number of people killed by pollution is undoubtedly higher and will be quantified once more research is done and new methods of assessing harmful impacts are developed.

Areas like Sub-Saharan Africa have yet to even set up air pollution monitoring systems. Soil pollution has received scant attention. And there are plenty of potential toxins still being ignored, with less than half of the 5,000 new chemicals widely dispersed throughout the environment since 1950 having been tested for safety or toxicity.

Asia and Africa are the regions putting the most people at risk, the study found, while India tops the list of individual countries.

One out of every four premature deaths in India in 2015, or some 2.5 million, was attributed to pollution, the study found.

China's environment was the second deadliest, with more than 1.8 million premature deaths, or one in five, blamed on pollution-related illness.

Air pollution is a major problem in Beijing, China. ( Reuters: Claro Cortes, File )

Several other countries such Bangladesh, Pakistan, North Korea, South Sudan and Haiti also saw nearly a fifth of their premature deaths caused by pollution.

To reach its figures, the study's authors used methods outlined by the US Environmental Protection Agency for assessing field data from soil tests, as well as with air and water pollution data from the Global Burden of Disease, an ongoing study run by institutions including the World Health Organisation and the Institute for Health Metrics and Evaluation at the University of Washington.

Even the conservative estimate of 9 million pollution-related deaths is one-and-a-half times higher than the number of people killed by smoking, three times the number killed by AIDS, tuberculosis and malaria combined, more than six times the number killed in road accidents, and 15 times the number killed in war or other forms of violence, according to GBD tallies.

Poorer countries most at risk

It is most often the world's poorest who suffer. The vast majority of pollution-related deaths — 92 per cent — occur in low or middle-income developing countries, where policy makers are chiefly concerned with developing their economies, lifting people out of poverty and building basic infrastructure, the study found.

Environmental regulations in those countries tend to be weaker, and industries lean on outdated technologies and dirtier fuels.

India has the highest rate of pollution-related premature deaths. ( AP: Manish Swarup, File )

In wealthier countries where overall pollution is not as rampant, it is still the poorest communities that are more often exposed, the report said.

"What people don't realise is that pollution does damage to economies. People who are sick or dead cannot contribute to the economy. They need to be looked after," Richard Fuller, head of the global toxic watchdog Pure Earth and one of the 47 scientists, policy makers and public health experts who contributed to the 51-page report, said.

"There is this myth that finance ministers still live by, that you have to let industry pollute or else you won't develop," he said.

"It just isn't true."

The report cites EPA research showing that the US has gained about $38 in benefits for every dollar spent on controlling air pollution since 1970, when Congress enacted the Clean Air Act, one of the world's most ambitious environmental laws.

Removing lead from gasoline has earned the US economy another $7.6 trillion cumulatively since 1980, according to studies by the US Centres for Disease Control and Prevention.

Some experts cautioned, however, that the report's economic message was murky.

Reducing the pollution quantified in the report might impact production, and so would not likely translate into gains equal to the $5.9 trillion in economic losses.

Pollution is increasingly becoming a serious health concern in developed countries. ( AP: Michel Euler (File) )

While there has never been an international declaration on pollution, the topic is gaining traction.

The World Bank in April declared that reducing pollution, in all forms, would now be a global priority. And in December, the United Nations will host its first-ever conference on the topic of pollution.

"The relationship between pollution and poverty is very clear," Ernesto Sanchez-Triana, lead environmental specialist at the World Bank, said.

"And controlling pollution would help us address many other problems, from climate change to malnutrition. The linkages can't be ignored."

AP