HOUSTON, Oct. 23 (Xinhua) -- Texas remains to be the biggest greenhouse gas emitter in the United States, according to a report released Wednesday by the U.S. Environmental Protection Agency (EPA).

　　Texas emitted more than 392 million metric tons of carbon dioxide in 2012, more than double that of any other state. The second-largest emitter was Indiana, with 155.1 million metric tons, the report says.

　　Texas ranked high on the list because it is home to many of the largest industrial polluters, including petroleum refineries, power plants and chemical facilities.

　　The EPA's findings are based on data collected last year from over 8,000 facilities in the largest emitting industries, including power plants, oil and gas production and refining, iron and steel mills, and landfills.

　　The report shows a 4.5 percent drop in carbon pollution nationwide, largely due to a shift from burning coal to natural gas and a slight drop in electricity production.

　　Though emissions from power plants have decreased 10 percent in the following two years since the EPA launched the report, fossil-fuel power plants remain the largest contributor to U.S. greenhouse gas emissions.

　　With less than 1,600 facilities emitting over 2 billion metric tons of carbon dioxide in 2012, these plants account for roughly 40 percent of the total U.S. carbon pollution.

　　The greenhouse gas pollution, most of which is from carbon dioxide emissions, is believed to be the primary driver of recent global climate change, which threatens the health and welfare of human beings.

　　It could increase the likelihood of hotter, longer heat waves, fuel more frequent and intense extreme weather events, and worsen ground level ozone, an air pollutant that causes respiratory and cardiovascular health problems.