A recent environmental study at LAX tested the levels of air pollutants in the area. And although the study found that most of the pollutant levels were below federal standards, the level of ultrafine particles was higher than expected. There is no existing legislation on ultrafine particle levels, mostly because their health effects are not well understood, but LAX officials would like to be proactive about the issue. An especially interesting aspect of these ultrafine particles is that they may be the result of more efficient engines, which most people would consider a good thing (financially and environmentally). The more efficient automobile and jet engines use more of their fuel, leaving smaller particles in their wake. This issue is an intriguing example of how attempts to improve environmental quality can lead to new and unexpected issues.
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