President Donald Trump’s weakening of pollution and fuel-efficiency standards for new cars will lead to as many as 299 premature deaths annually by midcentury, while also doing nothing to rein in potentially catastrophic global warming, according to the government’s official environmental analysis of the policy.

The proposed change in standards, rolled out in August, would also cost Americans nearly 17,000 days of work a year because of increased illnesses, the analysis by the National Highway Traffic Safety Administration says.

Though the proposed standards and the environmental impact statement came out in August, scrutiny of the document has increased in recent days, with the opening of public hearings around the country. Critics say the administration’s own environmental analysis proves why the mileage standards for new cars, and the amount of pollution they are allowed to emit into the air, should not be weakened, as the new proposal recommends.

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“Premature death is the ultimate health effect and this policy, taken with many other policies being proposed by this administration, are all leading to more air pollution,” said Paul Billings, senior vice president for advocacy at the American Lung Association. “And that is leading to these clear adverse health effects.”

The only big winners in this would seem to be the oil companies."

The Trump policy would significantly weaken standards for cars, freezing them after 2021 at about 37 miles per gallon. It would eliminate rules drawn under President Barack Obama that would require cars and light trucks to average about 54 miles per gallon by 2025. The Trump policy also attempts to take away the waiver granted to California and other states to set their own more stringent standards, a change that the states are fighting in court.

Trump appointees in the Department of Energy and the Environmental Protection Agency argue that the easing of standards will usher in an era of cheaper vehicles, while preserving U.S. manufacturing jobs. Opponents say that carmakers were poised to meet the tougher standards and that the U.S. will be left behind as the rest of the world switches to less polluting cars.

The likely negative health impacts from allowing more pollution are outlined in a chart deep in the NHTSA’s environmental impact statement. It predicts 199 additional cases of acute bronchitis a year, 62 added emergency room visits from respiratory distress annually and a total of 16,819 missed work days per year. The premature death total of 299 annually would come under one predictive model, while another model suggests premature deaths would top out at 134 a year.

The negative health outcomes could be overcome with other actions, like different emissions regulations or changes in consumer behavior, say toward buying more electric cars, the analysis says. But environmental groups say those are the sorts of changes that Trump's policies have thwarted.

The report also projects that, under current policies, the Earth would warm by 7 degrees Fahrenheit over pre-Industrial levels by the year 2100, as first reported by The Washington Post. That is well above the 2 degrees Celsius (or 3.6 degrees Fahrenheit) increase that scientists say the Earth must maintain to prevent catastrophic outcomes. The 7 degree increase anticipated in the fuel efficiency report likely would trigger flooding of New York, Miami and other coastal cities, along with a string of other disasters, researchers say.

“The only big winners in this would seem to be the oil companies,” said David Pettit, a senior attorney with the Natural Resources Defense Council. “The whole point of the rollback is to make cars less fuel efficient, so they burn more gas. For this administration, that is a more important value than 299 people a year dying early or 7 degrees of warming….which will make much of the U.S. a wasteland.”

Asked to respond to questions about the findings, an Environmental Protection Agency spokesman referred NBC News back to the agency's original announcement about the vehicle pollution rules.