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Researchers say more studies are needed to figure out how air traffic at Moffett Field in Mountain View could be affecting lead levels in children. Courtesy NASA.

For the 52,000 residents living around the Reid-Hillview Airport in San Jose, there’s a public health threat looming over the community. Daily aircraft traffic is contaminating the area with lead, and it’s causing a spike in the blood lead levels in children, according to a new study commissioned by Santa Clara County that noted other area airports are also likely contaminating local communities.

The study, released Tuesday, found that children living within 1.5 miles of the Reid-Hillview Airport have elevated levels of lead in their blood, and that the problem gets much worse for those who live closer to or downwind from the airport. County officials say the worrying findings show a spike in blood lead levels as significant as the height of the Flint water crisis in Michigan.

County Supervisor Cindy Chavez said the results are “rock solid” evidence that airport traffic is harming the public, and that exposure to lead is particularly harmful in children. It can lead to lower IQs, decreased success in school, behavioral problems, hypertension and coronary disease.

“What this very thorough study proves is that we literally have a crisis on our hands,” Chavez said at a press conference Tuesday. “This is a public health issue, it’s an environmental justice issue and it’s an equity issue.”

The study dove into public health data spanning a decade, and found that children under the age of 18 living close to Reid-Hillview had blood lead levels over 1.8 micrograms per deciliter. In 3.2% of the children surveyed, that number was as high as 3.5 micrograms, and in 1.7% of children it was 4.5 micrograms. Average baseline lead levels in children across the U.S. are closer to 0.84 micrograms.

Children can suffer substantial and long-lasting health effects from even low levels of lead in the blood, and the Centers for Disease Control and Prevention (CDC) has concluded that there are no safe blood lead levels in children.

Though the analysis honed in on residents living around Reid-Hillview, the study notes that all airports in Santa Clara County servicing piston engine aircrafts — which use leaded aviation gasoline — are likely contaminating other communities as well. Moffett Federal Airfield, Palo Alto Airport, Norman Y. Mineta San Jose International Airport and the San Martin Airport all serve planes that leave behind lead that can be inhaled and ingested by residents below.

Advantage Aviation flight instructor Jimena A. Kho, left, and student pilot Andy Smith prepare for a lesson at the Palo Alto Airport on Sept. 18, 2019. Photo by Sammy Dallal.

The study compiled 2,500 records from these airports, including health records of children, and found similar results.

“Again, we find that child blood lead levels decrease with distance from the nearest airport, are significantly higher among children residing east of the nearest airport, and increase with the volume of piston engine aircraft traffic,” according to the study.

But Sammy Zahran, the author of the study, said he would caution against generalizing the results of the study for all airports in the county, and that each airport is different in terms of volume of traffic and proximity for neighborhoods. In some cases — like at San Martin — the available public health data was paltry, and only 68 children were sampled over a 10-year period.

“I think it would be important to perform analyses at these other airports,” he said.

Chavez also advocated for a broad approach, and said up to 4 million people across the country live within a short distance from airports and could be subject to the same health hazards.

“This issue needs to be resolved both in our community … but it’s also an issue that the FAA (Federal Aviation Administration) and the federal government need to address in order to make it safe for people to breathe the air if they live near an airport.”

Santa Clara County Supervisor Cindy Chavez is raising public health concerns over high blood lead levels found in residents living near airports. Screenshot obtained via Santa Clara County video.

Reid-Hillview Airport has been the subject of scrutiny in recent years, operating right alongside homes and near several schools in east San Jose. Though automobiles have operated on unleaded gasoline for decades, aircraft taking off and landing at Reid-Hillview are still using leaded aviation fuel, spreading the toxic metal in a concentrated ring around the airport.

In 2018, the Santa Clara County Board of Supervisors voted narrowly 3-2 to stop accepting federal grants to operate Reid-Hillview, opening an opportunity for the county to shut down the airport as soon as 2031. Chavez said the study adds a sense of urgency, and that the significant hazards to children living near the airport could be used to petition the FAA for a faster closure. The board is scheduled to review the study at a meeting on Aug. 17.

Dr. Bruce Lanphear, a pediatric epidemiologist, said the airborne lead settles on the windowsills, tabletops and floors of the homes below, putting young children and toddlers at particularly high risk of ingesting the lead. He said the study on Reid-Hillview is one of the most thorough and conclusive reports he’s read over the course of his 25-year career and accounts for all other sources of lead, including lead-based paint that remains in many older households.

“The results all point to the same conclusion — the Reid-Hillview Airport endangers the lives of people who live around the airport, and especially children,” Lanphear said.

Blood samples of children around Reid-Hillview show that residents living within half a mile of the airport are at higher risk than those between a half-mile and 1.5 miles away, with an average 0.2-microgram per deciliter increase for those living in the nearest orbit. That spike alone is roughly half of the estimated increase in blood lead levels examined during the Flint water crisis, Zahran said, but with one key difference: The airport’s emissions have been constant for far longer.

“The height of the Flint water crisis, from start to finish, unfolded in less than a year and a half,” he said. “By contrast, at Reid-Hillview, the release of lead into the lived community is continuous — a daily, unabated stream of an undeniable harmful toxin.”

Chavez described the airport as an “incongruous” land use with the nearby residential neighborhoods, and said that the brunt of the health impacts harm residents who are least affluent in the community. Almost half of the households have a high school diploma, and more than 75% speak a language other than English at home, she said.

Kevin Forestieri writes for the Mountain View Voice, a sister publication of PaloAltoOnline.com.

Kevin Forestieri writes for the Mountain View Voice, a sister publication of PaloAltoOnline.com.

Kevin Forestieri writes for the Mountain View Voice, a sister publication of PaloAltoOnline.com.

Kevin Forestieri writes for the Mountain View Voice, a sister publication of PaloAltoOnline.com.

Kevin Forestieri is the editor of Mountain View Voice, joining the company in 2014. Kevin has covered local and regional stories on housing, education and health care, including extensive coverage of Santa...

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8 Comments

  1. The first unleaded fuel for general aviation aircraft has just been approved by the FAA this month. This was announced at EAA AirVenture. Right now this GAMI fuel is only approved for the Cessna 172, but hopefully will be approved for all other planes over the next year.

  2. As a child I remember the old playgrounds where I played for hours with lead paint on all the structures. I remember the paint peeling off behind the garage in my childhood home. I remember the old oven gloves made of asbestos. I remember walking to school smelling the lead in the exhaust of the traffic as I stood waiting for the lights to change so I could cross, or walking along the road where the lines of cars waiting for the lights to turn green were spewing out their exhaust just feet from my nose.

    I remember all those things. I am so thankful that children today do not have those in their lives.

  3. Those studies are motivated by developers who want to build on the grounds of Reid Hillview airport. Did the lead found come from airplanes fuel? Is there comparison with a similar community far from an airport? Airplanes are few, they spend a short time on the ground with engines on and it is not clear how much of that lead reaches humans. It might come from lead deposits on highways and roads from the times that leaded fuel was common. On the other hand airports are being closed around the country like a species that i becoming extinct. They serve the community, especially in disasters and pandemics, they are great recreational facilities. They also leave open space in congested cities. We should strive to remove lead as as we have done with cars but not take commercially motivated “studies” too seriously.

  4. Given what we know about lead exposure and how long we’ve known it, it is tragic that we outlawed leaded gasoline for land vehicles decades ago and ignored aircraft until now.

  5. Developers continue to try to shut down any open space or other use of space that doesn’t allow them to continue to pave over the state. The airport was there first. All developers (and elected representatives who help them) who built homes surrounding the airport area should be held responsible for moving residents as needed and any clean up needed. These are low income areas because who else do you get to live under airfield flight paths and these people have been taken advantage of and will be continually used to try to pressure the closure of this facility.
    We need these small airports for emergencies, disaster preparedness and community open spaces. They were here first and deserve priority in usage of the area. Of course we need to continue to remove toxic substances where feasible like in airplane fuel. Developers need to be told that the state is full and to go get another job since they are no longer wanted and are making live unbearable in a very crowded state. Do not close the airport to support developers who should go the way of coal mining.

  6. An investigation is needed to determine whether similar contamination is occurring in Palo Alto due to the Palo Alto Airport, SFO, and SJC planes flying non-stop across city airspace. If such contamination is occurring, traffic needs to be routed 100% over the bay or over the baylands, not over residential areas in the City of Palo Alto. There is especially no reason that planes headed to SFO (two counties north of Santa Clara County) should ever fly below 10,000 feet over Palo Alto airspace.

  7. One concern for the Palo Alto Airport is that there are groups that want to expand the business base by adding commuter planes and commuter helicopters. That is moving the rationale for the airport from private flyers and flying clubs to commercial entities which would have a non-stop activity level. That should be looked at as it was not the original reason for having the airport. And for the residents it is not a reasonable activity to have non-stop air traffic from multiple sources.

  8. “An investigation is needed to determine whether similar contamination is occurring in Palo Alto due to the Palo Alto Airport, SFO, and SJC planes flying non-stop across city airspace. “

    Jet-A, used in turbine engined planes (i.e., most of the passenger aircraft in-and-out of SFO/SJC/OAK) is unleaded. While I agree it would be good to reroute passenger jets away from Palo Alto, leaded fuel is not the right horse on which to ride.

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