Imagine a vehicle that gives off 30 times more harmful nitrogen oxide and 60 times more particulate matter than a modern truck.

Now consider the dangers those emissions pose by contributing to acid rain and smog, and wreaking havoc on vulnerable lungs.

Given New Jersey's densely packed cities and highly trafficked roads, it's a no-brainer that state Attorney General Gurbir Grewel acted last week to join 15 other states in suing the U.S. Environmental Protection Agency to minimize the dangers these super-polluting trucks pose.

At issue is the suspension of a 2016 federal rule designed to keep "gliders" - vehicles that combine rebuilt truck engines with new bodies and cabs - off the roads in an effort to reduce their deadly effects.

The regulation, enacted in the final months of the Obama Administration, limited the sales of glider truck to 300 per manufacturer annually.

In one of his last actions before being ousted in the wake of scandals too numerous to count, former EPA head Scott Pruitt acted to ditch the policy. It was an overly generous gift to the freight truck industry, which sells about 10,000 of the reconstituted vehicles ever year. Pruitt's decision was no gift to the rest of us.

Andrew R. Wheeler, acting administrator of the Environmental Protection Agency, reversed the decision to allow more of these glider trucks on the roads. Wheeler's directive may be just a temporary reprieve, however. In an interview with the Washington Examiner, he described the Obama glider regulations as being unfair to truck manufacturers.

In New Jersey, the state's Department of Environmental Protection warns that trucks and other automobile traffic are the leading source of ozone pollution in the Garden State, giving off emissions that become smog after undergoing a chemical change.

And glider trucks are among the worst offenders.

DEP Commissioner Catherine McCabe calls them a dangerous throwback to a bygone era.

"They emit significantly higher amounts of particulates and nitrogen oxide into the atmosphere, putting at risk the health of people, particularly those who live along highways and in urban areas," McCabe said.

Inhaling smog compromises a person's respiratory system, leaving it inflamed and weakened. Environmentalists liken it to sunburn for the lungs.

In his obscene frenzy to undercut Barack Obama's legacy, President Donald Trump and his enablers are reversing years of environmental progress, in essence sending us back to the days of polluted air, befouled rivers and streams, and potentially dangerous food.

The damage will be incalculable. Its heirs will be our children and their children.

Grewel and his boss, Gov. Phil Murphy, recognize the threat and are right to lend the state's weight to the EPA lawsuit. Unlike Trump's minions, they have their priorities in the right place.

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