By Scott Christiansen
For the first time since the 1980s, Anchorage has an air quality monitoring station devoted to measuring lead in the air we breathe. The monitor is set next to a windsock on Merrill Field near the east end of Runway 25. It's there because piston-driven airplanes, unlike cars and trucks, still use fuel with lead added to boost octane. It's there because the federal Environmental Protection Agency is attempting to figure out if the most common source of lead in America's urban environs is a health hazard.
At the runway's opposite end is Fairview, one of Anchorage's oldest neighborhoods, with an elementary school and houses near the runway. Fairview also has a community council that has rarely, if ever, considered aviation exhaust a health hazard. There is a debate-a clash that includes politicians and environmental watchdog groups-about avgas (aviation gas) and how fast airplanes should switch to unleaded fuel, but just like the airplanes, that debate seems to fly over Fairview without stopping.
Michael Howard, Fairview Community Council's president, says when airport conversations start, the topic is usually noise. "The council would like to see some permanent noise monitoring put in place," Howard says. "As far as lead in their fuel, we didn't know anything about that."
But the air monitor at Merrill Field, like the neighboring windsock, is an early semaphore of weather to come. It's predictive of turbulence in the political winds that's already begun, even if it doesn't include airport-side neighborhoods such as Fairview. Alaska politicians-particularly those holding statewide offices-have lined up to play defense against an EPA action that seems destined to eliminate leaded avgas, just as the government eliminated leaded automobile gas.
The politicians warn that eliminating leaded avgas too fast could send the standard of living in airplane-dependent rural Alaska backward. Governor Sean Parnell, in a letter to the EPA, told the federal government that without a replacement fuel, a ban on leaded avgas "would truly be a disaster" costing billions of dollars and endangering health in rural Alaska. Rural villages, Parnell wrote, rely on piston aircraft to deliver medicine fuel and food.
When EPA announced in 2010 it would begin studying whether exhaust from airplanes should be regulated, Alaska congressman Don Young was quick to claim the agency was moving too fast. "This premature ban on leaded fuel would kill rural communities in Alaska," Young said in an April 2010 press release. Young's staff also quoted the congressman saying the EPA action was the result of a petition by Friends of the Earth, a national environmental watchdog group.
It is true that Friends of the Earth petitioned the EPA in 2006 to make a finding that leaded avgas is a health threat. It's also true President Richard Nixon signed the Clean Air Act in 1970, after Congress voted to pass it. It took more than two decades of tightening regulations and gradually improving technology to take lead out of automobile gas. In the meantime, little was done to put avgas in check. The watchdog group's petition is just one event in a series that includes the EPA tightening its air quality standards in 2008.
"We don't have the ability to ban avgas with a lawsuit," said Friends of the Earth spokeswoman Marcie Keever, a lawyer involved in the petition to the EPA. Keever says researchers are trying to find replacement fuels, and those must be approved by the Federal Aviation Administration, not the EPA. She says Friends of the Earth understands Alaska has challenges the Lower 48 doesn't have. "We do get that. In a lot of cases, transportation is different in Alaska," Keever said. The EPA has made exceptions in the past, Keever said, and can do that again. (Past allowances included an exemption for avgas stock car racing. NASCAR went lead free in 2008.) "The [EPA's] notice of proposed action, is not a notice of a proposed ban," Keever said.
Congressman Young reacted to the EPA studies with the typical bluster and posturing Alaskans have come to know well and re-elect time and again. Governor Parnell may have joined in the posturing, but he also sent a comparatively sober letter to Federal Aviation Administration urging the agency to appoint at least one Alaskan to a new task force that will study the fuel supply problem.
Alaska senators Mark Begich and Lisa Murkowski sent a joint letter to officials at EPA and FAA. Twenty-five other Senators signed the letter written by the Alaska delegation, which cites FAA requirements for octane-level in fuels and says "arbitrarily imposed" fuel requirements could make flying risky. "Despite ongoing research and testing, there is currently no safe or affordable alternative to leaded avgas," the letter says.
The air monitor at Merrill Field can be described as a vacuum that captures measured amounts of air, drawing it through a filter to trap pollutants. The Anchorage Health Department is running the tests with a grant from EPA. It's expected to cost about $44,000 for one year of monitoring, according to a program action plan provided by the department. The spot on the runway was chosen because of the high frequency of piston engines passing by, just before they power up and accelerate down.
Steve Morris, the city's air quality program manager, says EPA wants to know how much lead is in the air at a point of highest concentration. "If there is going to be high lead, it's going to be right there," Morris said. "The people of concern would be the pilots and airplane mechanics."
Morris would not release data from the Merrill field monitor for this story, saying it is premature. The study began in October and only samples taken over the first five weeks have been recorded. The system does not report air quality data in real time. Instead, filters are retrieved according to a set schedule and shipped to a lab for analysis. The program plan says the data will be combined with weather data, so the EPA will know what the weather was like when each sample was sucked into the monitor.
"So far it has been below the [EPA] standard, but it is hard to say what is going to happen in the future," Morris said.
Lead is a neurotoxin that can cause brain damage. The science is well documented and children are particularly vulnerable to lead in the environment. The EPA proclaimed a victory over leaded automobile gas in 1996, and recently the toxic metal makes headlines only if a toy or other children's product is recalled, or when old lead paint is discovered in a building. Standards for minimum lead exposure on a job site are set by the Occupational Safety and Health Administration, but the Center for Disease Control has never set a minimum exposure that is acceptable for children.
"There is no safe level of lead exposure," says Pam Miller of Alaska Community Action on Toxins, a statewide environmental health organization based in Anchorage. Miller said there's also no doubt Alaskans rely on airplanes.
The EPA monitoring program follows on the heels of other studies that show detectable lead is pumped into the environment through aviation exhaust every day. In Ontario, Canadian officials found air surrounding the Toronto-Buttonville Airport contained 4.2 times more lead than air in other parts of the city. Their report was published 11 years ago. In Chicago, the Illinois Environmental Protection Agency reported in 2002 that air monitors downwind from O'Hare Airport detected significantly higher lead than monitors upwind. A study in California at the Santa Monica airport found lead levels decreased the further away from an airport samples were taken, but did not equal Santa Monica's background levels until the monitor was 1,000 meters from the airfield.
The EPA itself has found children can ingest lead by breathing contaminated air or by direct contact with contaminated soil. It also found that aviation emissions account for almost 50 percent of the remaining airborne lead emissions in the U.S. (Lead smelters account for much of the rest.)
The most recent research was published last July in Environmental Health Perspectives and reported on a study of blood/lead levels in children that was conducted by researchers from Duke University.
The children were in six North Carolina counties, and data on lead in their blood came from a health surveillance program in that state. The study found a relationship between elevated blood/lead levels in children living within 1,000 meters of an airport, and further elevated among children living within 500 meters of an airport. The researchers noted that such a study is less practical in rural places but that their model could be extended to other states.
The Alaska Department of Health and Social Services conducts blood/lead surveillance, but the program is passive and only triggers investigation if elevated lead levels are reported by a doctor who requested a blood/lead test for a patient. Those incidents are rare enough that replicating the North Carolina study in Alaska might be impossible.
"Not every child in Alaska gets a blood/lead test," said Nim Ha, the state's acting program manager for environmental public health. Ha was not familiar with the North Carolina study, but said environmental exposures are difficult to quantify with a smaller population of patients. She says even outbreaks of food poisoning can go under the radar, if few people are exposed and even fewer seek medical attention. Longer-term effects of an environmental toxin would be even harder to track.
"We often face that challenge in Alaska," Ha said. "It is pretty rare that you can link an exposure to a health effect when it comes to toxins in the environment."
The EPA says removing lead from automobile gas reduced airborne lead concentrations nationwide, on average, by 91 percent, and removing leaded avgas from air pollution mix could cut the remaining 9 percent in half. Those statistics, combined with a "no safe level" stance from the CDC, have started political conversations and stirred citizen activity in communities in the Lower 48.
In Vero Beach, Florida, a group of residents petitioned their town last year to pay for soil samples on youth baseball fields near the municipal airport. The action came about after the Indian River County Health Department conducted blood/lead level surveillance in the area. Four cases of elevated levels were found, but none were attributed to the airport, according to the Vero Beach Press Journal. (Two were adults suspected to have occupational exposures. One child had lead levels that dropped on a second test, and a second child did not live near the airport.)
The Floridians are looking for lead in the ground of the baseball field because piston-driven airplanes have flown over the field for nearly 70 years. They figure the heavy parts of the exhaust fall somewhere. This particular ball field, according to the Press Journal, is 3,000 feet from the airfield, near the outside of the 1,000-meter buffer in the Santa Monica air quality study. (Beyond one kilometer, the California study found "background" lead levels.)
Vero Beach may be a bellwether for communities such as Fairview. The baseball parents seem to have the ear of local politicians. The town has a citizens' group called Airport Oversight Committee, and a local newspaper is set to report on tests for lead pollution as local leaders agree to pay for them.
The scientific question about whether lead in aviation exhaust is harmful may not yet be answered-it may never be answered-but that's not likely to stop either the federal government's march toward regulation or grassroots activities from flourishing in towns with busy general aviation airports.
Anchorage has two such airports, Merrill Field and Lake Hood, where leaded avgas is commonplace and where neighborhoods are close enough a pilot can look down a soccer mom's blouse. Stephen Morris, the city air quality manager, says right now there are no lead monitors other than the one at Merrill Field. He said that doesn't mean the monitoring won't be expanded, especially if a year's worth of data finds lead levels exceeding EPA ambient air standards for the city.
It's not unheard of for Anchorage to go a step beyond federal standards when it comes to environmental health. Morris says his department is conducting a study of Anchorage's indoor air, specifically studying benzene in homes with attached garages. The city launched the benzene study on its own initiative-it's funded by a grant from EPA, but the Anchorage Health Department is not required to conduct it.
"We could [expand the lead monitoring] and we could certainly do it as a local initiative even if the EPA was not interested in monitoring lead as a local concern," he said.
Source: http://www.anchoragepress.com
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