China is already home to 16 of the planet's 20 most heavily polluted cities -- a noxious byproduct of its double-digit economic growth.
Seven of 10 homes still burn coal and wood for heat, and half of Chinese men smoke -- a toxic combination of indoor pollution that raises dire questions about the fate of this industrial giant's long-term public health.
Over the next quarter-century, 83 million Chinese -- a number equaling nearly a third of the total U.S. population -- will die from lung cancer and respiratory ailments without the reduction of cigarette smoking and indoor fuel-burning, a new study by Harvard's School of Public Health warns.
"In many places in rural China, the roads are good, people now have cellphones and electricity, but residents are still cooking and heating with the same fuel they have used for centuries," said Majid Ezzati, an associate professor of international health and senior author of the study. "And as a result, people are dying."
In an article published this month in the Lancet medical journal, the Harvard team also concludes that programs to reduce smoking and household use of coal and biomass fuels such as wood for cooking and heating could significantly reduce the deaths.
The question, researchers say, is whether the Chinese government has the political willpower to enact sound public health policy.
"This analysis shows that smoking and fuel use, which affects hundreds of millions of people in China, will be a defining feature of future health in that country," said Hsien-Ho Lin, a graduate student in the department of epidemiology at Harvard's School of Public Health and the lead author of the study.
Ezzati said he was working a few years ago in central China when his team noticed the high number of deaths, which residents did not seem to attribute to their household habits.
"People may know when they are in the house and it's very smoky . . . that it's making them cough -- their chest may hurt and their eyes burn. They talk about symptoms and discomfort," he said.
"They know there is something that's not good from their living conditions. But neither in China nor in other parts of the world do these people say: 'This is making me die early.' "