According to Kevin Swift, chief economist at the American Chemistry Council, European producers mostly use oil-derived raw materials for making these same products. “The U.S. has a competitive advantage when oil is seven times as expensive as natural gas, but now we have more like a 50-to-1 advantage,” he said. “The ‘shale gale’ is really driving this. A million B.T.U.’s of natural gas that might cost $11 in Europe and $14 in South Korea is $2.25 in the U.S. Partly because of that, chemical producers have plans to expand ethylene capacity in the U.S. by more than 25 percent between now and 2017.”

A 2011 PricewaterhouseCoopers study estimates that high rates of shale gas recovery could result in a million new manufacturing jobs by 2025. Robert McCutcheon, United States industrial products leader at PricewaterhouseCoopers, said in a statement that the revived natural gas industry “has the potential to spark a manufacturing renaissance in the U.S., including billions in cost savings, a significant number of new jobs and a greater investment in U.S. plants.”

The growing commitment to natural gas faces some headwinds because of continuing concern over the safety of fracking, which involves forcing pressurized fluids into shale formations to fracture the rock and release the gas deposits.

Some environmentalists say that fracking can cause drinking water to become contaminated with chemicals and released methane, which is a powerful naturally occurring greenhouse gas and the primary ingredient in natural gas. Other complaints tie the disposal of fracking wastewater to a series of small earthquakes. Some states and municipalities with questions about fracking have imposed temporary moratoriums on the extraction technique.

Despite these issues, natural gas is expanding its reach in manufacturing. The Nucor Corporation, which makes direct-reduced iron in a process heavily reliant on natural gas, said in 2010 that it would build a $750 million facility in Louisiana. In 2004, the company dismantled a similar Louisiana plant and shipped it to Trinidad.