"These are huge numbers. We're talking about millions of people," Shankar said. "So there is a lot of latent demand."
Yet there are some poor Indians trying to keep asbestos out of their communities, even as the government supports the industry by lowering import duties and using asbestos in construction of subsidized housing.
"People outside of India, they must be wondering what kind of fools we are," said Ajit Kumar Singh from the Indian Red Cross Society. "They don't use it. They must wonder why we would."
In the ancient farming village of Vaishali, in impoverished Bihar state, the first word about the dangers of asbestos came from chemistry and biology textbooks that a boy in a neighboring town brought home from school, according to villagers interviewed by The Associated Press.
A company was proposing an asbestos plant in the village of 1,500 people located about 1,000 kilometers (620 miles) east of New Delhi.
The villagers worried that asbestos fibers could blow from the factory across their wheat, rice and potato fields and into their tiny mud-and-thatch homes. Their children, they said, could contract lung diseases most Indian doctors would never test for, let alone treat. Neither India nor any of its 29 states keep statistics on how many people might be affected by asbestos.
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The people of Vaishali began protesting in January 2011. They objected that the structure would be closer to their homes than the legal limit of 500 meters (1,640 feet). Still, bricks were laid, temporary management offices were built and a hulking skeleton of steel beams went up across the tree-studded landscape.
The villagers circulated a petition demanding the factory be halted. But in December 2012, its permit was renewed, inciting more than 6,000 people from the region to rally on a main road, blocking traffic for 11 hours. They gave speeches and chanted "Asbestos causes cancer."
Amid the chaos, a few dozen villagers took matters into their own hands, pulling down the partially built factory, brick by brick.
"It was a moment of desperation. No one was listening to us," said a villager involved in the demolition, a teacher who spoke on condition of anonymity for fear of retribution from the company. "There was no other way for us to express our outrage."
Within four hours, the factory and offices were demolished: bricks, beams, pipes and asbestos roofing, all torn down. The steel frame was the only remnant left standing.
"Still, we did not feel triumphant," the teacher said. "We knew it wasn't over."
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They were right. The company filed lawsuits, still pending, against several villagers, alleging vandalism and theft.
Durable and heat-resistant, asbestos was long a favorite insulation material in the West, but has also been used in everything from shoes and dental fillings to fireproofing sprays, brake linings and ceiling tiles.
Scientists and medical experts overwhelmingly agree that inhaling any form of asbestos can lead to deadly diseases including mesothelioma, lung cancer and asbestosis, or the scarring of the lungs. Exposure may also lead to other debilitating ailments, including asthma and chronic obstructive pulmonary disease.
About 125 million people worldwide are exposed to asbestos at work each year, the WHO says. Because the disease typically takes 20 to 40 years to manifest, workers can go through their careers without realizing they are getting sick.
Dozens of countries including Japan, South Korea, Argentina, Saudi Arabia and all European Union nations have banned asbestos entirely. Others including the United States have severely curtailed its use.
Most asbestos on the world market today comes from Russia. Brazil, Kazakhstan and China also export, though some have been reviewing their positions.
Canada's Quebec province was the world's biggest asbestos producer for much of the 20th century. It got out of the business in 2012, after a new provincial government questioned why it was mining and exporting a material its own citizens shunned.
Asia is the biggest market. India last year imported $235 million worth of the stuff, or about half of the global trade.
The global asbestos lobby says the mineral has been unfairly maligned by Western nations that used it irresponsibly. It also says one of the six forms of asbestos is safe: chrysotile, or white asbestos, which accounts for more than 95 percent of all asbestos used since 1900, and all of what's used today.
"Chrysotile you can eat for breakfast, lunch and dinner!" said Kanat Kapbayel of Kazakhstan's United Minerals and a board member of the International Chrysotile Association.
Chrysotile is a serpentine mineral, meaning its fibers are curly and more flexible than the other more jagged and sharp forms called amphiboles. The lobby and its supporters say this distinction makes all the difference.
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A vast majority of experts in science and medicine reject this.
"A rigorous review of the epidemiological evidence confirms that all types of asbestos fiber are causally implicated in the development of various diseases and premature death," the Joint Policy Committee of the Societies of Epidemiology said in a 2012 position statement.
Squeezed out of the industrialized world, the asbestos industry is trying to build up new markets and has created lobbying organizations to help it sell asbestos to poor countries, particularly in Asia, it said.
Developed nations are still reckoning with health and economic consequences from past asbestos use.
American businesses have paid out at least $1.3 billion in the largest and longest-running collection of personal injury lawsuits in U.S. legal history, according to a 2012 report by the California-based Rand research corporation. Two years ago, an Italian court sentenced two businessmen from Swiss building material maker Eternit AG to 16 years in prison for negligence leading to more than 2,000 asbestos-related deaths. Billions of dollars have been spent stripping asbestos from buildings in the U.S. and Europe.
Arun Saraf, the Indian asbestos association's chairman, said India has learned from the West's mistakes.
He said the lobby's 15 member companies maintain the strictest safety standards in their factories. That includes limiting airborne dust, properly disposing of waste and insisting employees wear safety masks, gloves and protective clothing.
The vast majority of asbestos used in India is mixed with cement and poured into molds for corrugated roof sheets, wall panels or pipes. Fibers can be released when the sheets are sawed or hammered, and when wear and weather break them down. Scientists say those released fibers are just as dangerous as the raw mineral.
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AP journalists who visited a working factory and a shuttered one in Bihar found both had dumped broken sheets and raw material in fields or uncovered pits within the factory premises. Workers without any safety gear were seen handling the broken sheets at both factories. The working factory was operated by Ramco Industries Ltd., while the other owned by Nibhi Industries Pvt. Ltd. was supplying materials to UAL Industries Ltd.
Saraf, who is also UAL's managing director, said the materials left strewn across the factory grounds were meant to be pulverized and recycled into new roofing sheets, and were no more dangerous than the final product as the asbestos had already been mixed with cement.
He said Nibhi was not an association member, but "I have been informed that Nibhi workers are provided with all the personal protective equipment."
Some employees of Ramco's working factory said they were satisfied that asbestos was safe, and were delighted by the benefits of steady work. But several former employees of both factories said they were given masks only on inspection days, and rarely if ever had medical checkups. None was aware that going home with asbestos fibers on their clothing or hair could put their families at risk.
Ramco CEO Prem Shanker said all employees working in areas where asbestos was kept unmixed were given safety equipment and regular medical checkups that were reviewed by government authorities. "Ramco has consistently gone the extra mile to ensure a safe working environment," he said. AP was not given permission to visit these indoor areas.
Indian customers like the asbestos sheets because they're sturdy, heat resistant and quieter in the rain than tin or fiberglass. But most of all, they're cheap.
Umesh Kumar, a roadside vendor in Bihar's capital of Patna, sells precut 3-by-1 meter (10-by-3 foot) asbestos cement sheets for 600 rupees ($10) each. A tin or a fiberglass sheet of similar strength costs 800 rupees.
"I've known it's a health hazard for about 10 years, but what can we do? This is a country of poor people, and for less money they can have a roof over their heads," Kumar said.
"These people are not aware" of the health risks, he said. But as sellers of asbestos sheets wanting to stay in business, "we're not able to tell them much."
The two-day asbestos conference in December was billed as scientific. But organizers said they had no new research.
One could say they've gone back in time to defend their products.
The Indian asbestos lobby's website refers to 1998 WHO guidelines for controlled use of chrysotile, but skips updated WHO advice from 2007 suggesting that all asbestos be banned. The lobby also ignores the ILO's 2006 recommendation to ban asbestos, and refers only to its 1996 suggestion of strict regulations.
When asked why the association ignored the most recent advice, its executive director, John Nicodemus, waved his hand dismissively. "The WHO is scaremongering," he said.
Many of the speakers are regulars at asbestos conferences around the world, including in Brazil, Thailand, Malaysia, Ukraine and Indonesia.
American Robert Nolan, who heads a New York-based organization called Environmental Studies International, told the Indian delegates that "a ban is a little like a taboo in a primitive society," and that those who ban asbestos are "not looking at the facts."
David Bernstein, an American-born toxicologist based in Geneva, said that although chrysotile can cause disease if inhaled in large quantities or for prolonged periods, so could any tiny particle. He has published dozens of chrysotile-friendly studies and consulted for the Quebec-based Chrysotile Institute, which lost its Canadian government funding and shut down in 2012.
When asked by an audience member about funding for his research, he said some has come from chrysotile interests without elaborating on how much. A short-term study generally costs about $500,000, he said, and a long-term research project can cost up to about $4 million.