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A Geospatial Analysis of the Effects of Aviation Gasoline on Childhood Blood Lead Levels
Marie
Lynn Miranda, Rebecca Anthopolos, Douglas Hastings Marie Lynn Miranda ... 1003231 10.1289/ehp.1003231
Ahead of Print A Geospatial Analysis of the Effects of Aviation Gasoline on Childhood Blood Lead Levels Marie Lynn Miranda Research
Article, published 13 Jul 2011 | doi:10.1289/ehp.1003231
Background:
Aviation gasoline, commonly referred to as avgas, is a leaded fuel used in small aircraft. Recent concern about the effects
of lead emissions from planes has motivated the EPA to consider regulating leaded avgas.
Objective: This study investigates the relationship between lead from avgas and blood lead levels in children
living in six counties in North Carolina.
Methods: We used Geographic Information Systems (GIS) to approximate areas surrounding airports in which lead
from avgas may be present in elevated concentrations in air and may also be deposited to soil. We then used regression analysis
to examine the relationship between residential proximity to airports and NC blood lead surveillance data in children aged
9 months to 7 years while controlling for factors including age of housing, socioeconomic characteristics, and seasonality.
Results: Our results suggest that children living within 500 m of an airport at which planes use leaded avgas
have higher blood lead levels than other children. This apparent effect of avgas on blood lead levels was evident among children
living within 1000 m of airports. The estimated effect on blood lead levels exhibited a monotonically decreasing dose-response
pattern, with the largest impact on children living within 500 m.
Conclusions: We estimated a significant association between potential exposure to lead emissions from aviation
gasoline and blood lead levels in children. While the estimated increase was not especially large, the results of this study
are nonetheless directly relevant to the policy debate surrounding the regulation of leaded avgas.
· This EHP Ahead of Print
(AOP) article has been peer-reviewed, revised, and accepted for publication. The EHP Ahead of Print (AOP) articles are completely
citable using the assigned DOI code for the article. This document will be replaced with the copyedited and formatted version
as soon as it is available. Through the DOI number used in the citation, you will be able to access this document at each
stage of the publication process.
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Secondary aerosol formation from photochemical aging of aircraft exhaust in a smog chamber
Idling airplanes produce more harmful
pollution than previously thought
In a paper published in Atmospheric Chemistry and Physics, the team led by Allen Robinson, describe how they collected samples of exhaust from an idling KC-135 military cargo plane,
into large Teflon coated bags, and how they then exposed that exhaust to sunlight and/or UV light to initiate photo-oxidation (when a polymer surface degrades in oxygen or ozone). The result, they say, was that the original
droplets of oil were converted into multiple minute solid particles, small enough to penetrate the lungs and brain of people
working or living near airports.
In contrast, exhaust emissions from airplanes running at speed, such as when in-flight, tend to be mostly comprised of
solid particles, which would not be effected by sunlight in the same way, and thus would pose no additional health hazards
over what is already known about such types of pollution.
The paper highlights the fact that airplane pollution, and specifically the kind produced at airports, is in stark contrast
to other types of pollution emitters such as cars and manufacturing plants, in that little to nothing has been done to reduce
the amounts spewed into the environment. It also shows that the type of pollution produced at airports is far more hazardous
than was previously thought; but, because these findings are so new, it’s likely no research has yet been conducted
to ascertain what exactly happens to the human body when these tiny particles are breathed in on a regular basis.
The authors also mention in their paper, the folly of studying emissions from aircraft (or presumably any other pollution
emitters for that matter) without following up to find out what becomes of such pollutants as they enter the environment and
are affected by such forces as UV radiation, temperature, or other substances.
More information: Secondary aerosol formation from photochemical aging of aircraft
exhaust in a smog chamber, Atmos. Chem. Phys., 11, 4135-4147, 2011 doi:10.5194/acp-11-4135-2011
Abstract
Field experiments were performed to investigate the effects of photo-oxidation on fine particle emissions
from an in-use CFM56-2B gas turbine engine mounted on a KC-135 Stratotanker airframe. Emissions were sampled into a portable
smog chamber from a rake inlet installed one-meter downstream of the engine exit plane of a parked and chocked aircraft. The
chamber was then exposed to sunlight and/or UV lights to initiate photo-oxidation. Separate tests were performed at different
engine loads (4, 7, 30, 85 %). Photo-oxidation created substantial secondary particulate matter (PM), greatly exceeding the
direct PM emissions at each engine load after an hour or less of aging at typical summertime conditions. After several hours
of photo-oxidation, the ratio of secondary-to-primary PM mass was on average 35 ± 4.1, 17 ± 2.5, 60 ± 2.2, and 2.7 ± 1.1 for
the 4, 7, 30, and 85 % load experiments, respectively. The composition of secondary PM formed strongly depended on load. At
4 % load, secondary PM was dominated by secondary organic aerosol (SOA). At higher loads, the secondary PM was mainly secondary
sulfate. A traditional SOA model that accounts for SOA formation from single-ring aromatics and other volatile organic compounds
underpredicts the measured SOA formation by ~60 % at 4 % load and ~40 % at 85 % load. Large amounts of lower-volatiliy organic
vapors were measured in the exhaust; they represent a significant pool of SOA precursors that are not included in traditional
SOA models. These results underscore the importance of accounting for atmospheric processing when assessing the influence
of aircraft emissions on ambient PM levels. Models that do not account for this processing will likely underpredict the contribution
of aircraft emissions to local and regional air pollution.
© 2010 PhysOrg.com
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South Coast Air Quality Management District (SCAQMD)
Santa Monica Airport Air Quality Monitoring Studies
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Hidden threat: Elevated pollution
levels near regional airports
Environmental Science & Technology
Scientists are reporting evidence that air pollution — a well-recognized problem at major airports — may
pose an important but largely overlooked health concern for people living near smaller regional airports. Those airports are
becoming an increasingly important component of global air transport systems. The study, one of only a handful to examine
airborne pollutants near regional airports, suggests that officials should pay closer attention to these overlooked emissions,
which could cause health problems for local residents. It appears online in ACS’ Environmental Science & Technology, a semi-monthly journal.
In the new study, Suzanne
Paulson and colleagues note that scientists have known for years that aircraft emissions from fuel burned during takeoffs
and landings can have a serious impact on air quality near major airports. Aircraft exhaust includes pollutants linked to
a variety of health problems. However, researchers know little about the impact of such emissions at general aviation or regional
airports, which tend to be located closer to residential neighborhoods than major airports, the article notes.
The
scientists measured a range of air pollutants near a general aviation airport for private planes and corporate jets in Southern
California (Santa Monica Airport) in the spring and summer of 2008. They found that emissions of so-called ultrafine particles,
which are less than 1/500th width of a human hair, were significantly elevated when compared to background pollution levels.
Levels of these pollutants were up to 10 times higher at a downwind distance from the airport equal to about one football
field and as much as 2.5 times higher at distance equal to about six football fields. The study suggests that “current
land-use practices of reduced buffer areas around local airports may be insufficient.”
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Santa Monica Airport
Health Impact Assessment (HIA)
February 2010
A health-directed summary of the issues facing
the community near Santa Monica Airport
Written by UCLA CHAT PGY-2 Pediatric Residents
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PLANE SMOG:
AN ASSESSMENT OF THE SOURCES
OF LAX AIR POLLUTION
ON THE LOCAL AND GLOBAL ENVIRONMENT
click here to view Plane Smog
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*On August 21, 2003, the AQMD held a conference on the Precautionary Principle.
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*Controlling Airport-Related Air Pollution
Prepared by
Northeast States for
Coordinated Air Use Management
and
Center
for Clean Air Policy
June, 2003
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FEDERAL AVIATION ADMINISTRATION
- WASHINGTON, DC - MAR 85
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