Talk about disappearing into thin air.
One night before local access lanes to New Jersey's George Washington Bridge were closed last fall in an apparent act of political retribution that sparked miles-long traffic jams for four straight days, an air quality monitor run by the New Jersey Department of Environmental Protection in Trenton abruptly ceased collecting data.
The closest state-run monitor to the bridge with its data posted online, the monitor started measuring air pollution again more than two days later – just as a key pollution indicator was starting to decline.
"They're missing data for 2 1/2 days – that's weird," says Ann Marie Carlton, an assistant professor at Rutgers University who studies air quality.
"I was really, really shocked when I saw there was no data. You might see a monitor go offline for a day because they're cleaning it or doing maintenance or calibration, but for it go down for this many days is intriguing."
"Bridgegate" has been a headache for New Jersey Gov. Chris Christie, a Republican who insists he was not aware of plans for the gridlock. He has since fired a top aide who appears to have ordered the lane closures as payback against a mayor who did not back Christie's re-election bid.
Last fall was not the first time the monitor went down – it stopped transmitting data for several hours on two occasions in June, and it went offline for nearly a week at a time in March and November 2012.
Nevertheless, data collected just as the Jersey monitor came back online, supplemented by another monitor in Newark, suggest that air pollution reached potentially dangerous levels during at least part of the lane-closure period from Sept. 9 to 12, as thousands of cars, trucks and buses waited for as long as four hours to cross the bridge.
The monitor, placed atop a firehouse in Jersey City, measured the amount of diesel, oil and other fuel particles in the air. Each particle measures 2.5 micrometers or smaller – about 1/30th the width of a human hair – and together they're known as PM2.5.
At 1 p.m. on Sept. 11 – the third day of the lane closures and the first time the monitor started collecting data after going offline – there were 28.2 micrograms per cubic meter of PM2.5 in the air around Jersey City, according to the monitor's measurements. That amount is double the maximum measured on Sept. 8, the day the monitor turned off.
At the Newark station 5 miles farther away, there were 40.4 micrograms per cubic meter in the air – 5 micrograms higher than federal guidelines implemented under President George W. Bush.
"If you had smokers in a bar, or if you were in a home where a spouse smokes a pack and a half of cigarettes per day, you'd expect exposure to be about 35 [micrograms per cubic meter]," says C. Arden Pope, an economics professor at Brigham Young University who studies air pollution. "The health risks – they're not massive, they're relatively small, but the effects are spread out over an entire population of breathers, and it's involuntary. It's not like they're choosing to smoke or they're choosing to be exposed to this."
As George Thurston, New York University professor of population health and environmental medicine, describes, "Any increase in pollution is of concern, because that increases your risk."
And that risk rises, he continues, if pollution levels remain high.
"It's like a heat wave," he says. "If you're suffering from a one-day heat spell, we don't see that many people dying. But when you have multiple, recurring days from extreme heat, we see death rates go up. You get multiple days, and the impact of those multiple days is much worse."
The New Jersey Department of Environmental Protection declined to comment Tuesday afternoon, referring questions to Christie's office.
The governor's office did not return a call and email for comment. Government offices in New Jersey shut down Tuesday due to heavy snowstorms in the region.