Response to Letter to the Editor by Eve Lopez, SMDP at smdp.com, March 4, 2022:

Pilot Eve Lopez has cherry-picked data from the study about children’s blood level conducted at Santa Clara Airport to try to justify her faulty claims.  In response to Airport Commissioner Joseph Schmitz’s March 28, 2022 letter to SMDP, raising concerns about the use of leaded aviation gas (avgas) at the Santa Monica Airport, Ms. Lopez argues that “The Commissioner’s statement that Santa Monica has failed to curb children’s lead poisoning by toxic avgas is not supported by the Santa Clara study and reflects a motive dressed up as a pretext of health concerns for children.”  She is incorrect – and her statement shows that she fails to understand the serious health effects of lead exposure for children.  

The study’s authors main goal was to look at increasing proximity to the airport; they concluded that the closer to the airport children lived, the more elevated were their blood lead levels.  (See:   https://news.sccgov.org/sites/g/files/exjcpb956/files/documents/RHV-Airborne-Lead-Study-Report.pdf).

The study’s RESULTS section states: 

1. “Children residing within 0.5 miles of Reid-Hillview Airport present with significantly higher BLLs than children more distant of Reid-Hillview Airport.”

2. “BLLs are significantly and substantively higher among sampled children residing East (and predominantly downwind) of Reid-Hillview Airport….” 

3. “BLLs of sampled children increase significantly with the volume of measured piston-engine aircraft traffic at Reid-Hillview Airport from the date of blood draw. Moreover, the BLLs of sampled children increase significantly with monthly quantities of aviation gasoline sold to fixed-base operators at Reid-Hillview Airport from the date of blood draw.”

The study’s authors state:  

• “The evidence … suggests that children residing within 0.5 miles of Reid-Hillview Airport are especially vulnerable to increases in PEA [piston-engine aircraft] traffic.” 

• “Children more distant from Reid-Hillview Airport (0.5 to 1.5 miles) experience a modest increase in BLLs of about 1/10th of µg/dL from an increase in PEA traffic from the minimum to the maximum.” 

• “By contrast, among sampled children at < 0.5 miles of Reid-Hillview Airport, an increase from the minimum to maximum exposure to PEA traffic is associated with an estimated 0.83 µg/dL increase in BLLs – an effect that is substantively higher than the increase in BLLs caused by water system failures during the FWC [Flint Water Crisis].”

Their study is consistent with other studies:

“The U.S. EPA estimates that people living within 1 km [0.62 mile] of airports are at risk of being exposed to lead from avgas.”  (Hitchings M. 2010. U.S. EPA aims to slash aviation gasoline emissions. Glob Refining Fuels Today 2:31–35). 

“Our analysis indicates that living within 1,000 m [0.6 mile] of an airport where avgas is used may have a significant effect on blood lead levels in children. Our results further suggest that the impacts of avgas are highest among those children living closest to the airport. This study adds to the literature examining whether leaded avgas poses risks to children’s health and speaks directly to the ongoing policy debate regarding the regulation of leaded avgas.” Miranda, ML, et al.  A Geospatial Analysis of the Effects of Aviation Gasoline on Childhood Blood Lead Levels Vol. 119, No. 10. Environmental Health Perspectives. 1 October 2011 https://doi.org/10.1289/ehp.1003231.

Andrea Hricko, Santa Monica resident and retired clinical professor of environmental health, USC Keck School of Medicine