New Data Show L.A. Airport's Harmful Particulates Are Many Times Higher And Extend For Much Further Than Previously Assumed. Long Beach Airport Impacts, Combined With LB's Four Encircling Freeways Plus Twin Ports, RRs and Trucks, Not Yet Studied

(May 29, 2014, 11:25 p.m.) -- In a scientific study that could change the way airport impacts on residents are measured, evaluated and regulated, a team of scientists from USC's Keck School of Medicine and the University of Washington has found that health-impacting particles from operations at Los Angeles International Airport (LAX) are many times higher than previously assumed and the adverse impacts extend for miles, much further than in previous airport studies.

The scientists say the results suggest that airport emissions are a major source of particle pollution in Los Angeles [abstract quoted text] "that are of the same general magnitude as the entire urgan freeway network" and results "also indicate that the air quality impact areas of major airports may have been seriously underestimated."

Image from emission study

The scientists' work, published in Environmental Science and Technology and accessible at this link, didn't evaluate conditions in Long Beach, which has a municipal airport smaller in size and operations than LAX but is also encircled by four freeways only a few miles from the L.A.-Long Beach Port complex (previously identified as the region's worst cumulative source of pollutants from ships, trucks, trains and "goods movement.")

The study's authors conclude that LAX produces a particulate impact roughly equivalent to a 280-790 km (roughly 180-490 mile) freeway. (L.A.'s total freeway length is 1,500 km or about 930 miles.)

Under "Recommendations for Other Studies," the authors state:

LAX is in a region of Los Angeles with highly consistent wind direction. This provided the several hours necessary for a single mobile platform to monitor a sufficient number of transects to cover the large area impacted by LAX emissions. At airport locations where the prevailing wind direction frequently shifts during the day, multiple platforms would be necessary to quickly capture the full spatial extent of emissions impacts to surrounding air quality. The emissions from LAX are likely not unique on a per-activity basis. The large area of impact from LAX suggests that air pollution studies involving PN, localized roadway impacts, or other sources whose impacts are in the influence zone of a large airport should carefully consider wind conditions and whether measurements are influenced by airport emissions. Source apportionment of specific airport sources or activities was beyond the scope of our study but would be necessary to evaluate the effectiveness of possible mitigation options. Differing NO2 to NOx ratios at different levels of engine thrust(20) might be used to distinguish the contributions of jet landing, idling or takeoff activities. Takeoff and idling emission also differ in surface properties (i.e., the ratio of active surface area to surface bound photoionizable species)(21) and particle size distributions differ between aircraft and ground support equipment emissions.(21)

The study could be a game-changer for the way in which airport impacts are discussed. Decades ago, Long Beach airport's impacts were evaluated solely in terms of noise, but the new study provides reasons to update the terms of such discussions. Particulate pollution from airports is arguably analogous to that of seaports, where the need was once resisted but is now-acknowledged to mitigate and reduce such impacts.

The full study, titled "Emissions from an International Airport Increase Particle Number Concentrations 4-fold at 10 km Downwind," can be viewed by clicking here.