On the environmental-threat-level scale, climate change clearly poses the gravest long-term risk. But in the shorter term? That would surely be air pollution. Millions of people are dying from air pollution already.
In a new report, the World Health Organization estimates that 7 million souls perished prematurely in 2012 as result of the diseases caused by indoor and outdoor air pollution. That's one-in-eight of all fatalities that year. The vast majority—more than 5 million—were in Southeast Asia (which includes Indonesia) and the Western Pacific (China and the Philippines). Almost all the deaths occurred in lower- and middle- income countries.
These latest numbers are higher than previously estimated either by the WHO or other researchers. For example, a study last year focusing on outdoor pollution put the death count at 2.1 million globally. The new study gives a figure of 3.7 million.
The WHO says the higher estimates are the result of a better understanding about pollution-related diseases, and monitoring technology that takes account of more demographic groups, including communities in rural areas. Heart disease and stroke account for 80% of outdoor pollution deaths, it says, and 60% of indoor deaths.
Of course, the immediate and long-term threats of air pollution and climate change are related. The same coal-burning electricity plants near Beijing both affect people's health now and contribute to emissions build-up that will change the climate in the future. Similarly, the soot from inefficient cookstoves kills folks in the present (the report attributes 4.3 million deaths to household air pollution) and causes global warming. "Black carbon" is the second most important greenhouse gas pollutant after carbon dioxide.
The WHO says, from a societal perspective, more sustainable practices in industries such as transport, energy, waste management would pay for themselves. "In most cases, healthier strategies will also be more economical in the long term due to health care cost savings as well as climate gains," says Carlos Dora, the WHO's public and environmental health coordinator, in a press release.