Scientific Oversight Committee Recommendation to Continue the Study

We submitted our progress report to the Scientific Oversight Committee (SOC) on December 11, 2025. The SOC completed its evaluation of the report and recommended continuation of the Study. By the terms of our contract with the LA County Department of Public Health, we must undergo another review by the SOC after the end of this year.

Resident Health Survey and Clinical Assessments

The survey was officially launched in late October 2025. We have sent more than 57,000 invitation letters to date and have received about 1,300 completed surveys and scheduled or completed 280 clinical assessments. Additional invitation letters and reminders will be mailed until 2,000 surveys and 600 clinical assessments are completed.

Please continue to watch your mailbox for a potential invitation letter at your home address to participate in the survey and remind your neighbors to do the same. Every household has a chance to be selected. If you receive the letter, please respond promptly and make sure to respond to the clinical assessment consent question at the end of the survey.

State Lab Neonatal Blood Spots for Metabolomics Analysis

After a long approval process, the State biobank has completed pulling 2,600 blood spots from storage and the Study team received the blood spots for analysis. The blood spots are from babies born to mothers living in the affected community and the comparison communities before, during, and after the blowout.

With these data, the metabolomics analysis will identify markers of exposure to the blowout present in blood samples and associated health risks of these exposures. Our results will supply quantifiable, clinically meaningful indicators of exposure and potential health risks to the babies affected by the disaster and longer-term exposures from the Aliso facility.

Upcoming Study Publication Activities

We recently published a paper entitled, “Estimated impact of the Aliso Canyon disaster on emergency department visits” in the highly cited journal Environment International. It described how emergency department use rose significantly during and after the 2015–16 Aliso Canyon gas blowout. For more details read the press release and the full publication.

The following studies will be submitted soon:

• Methods for exposure risk assessment (preliminary results presented at Community Meeting #4)

• Impact of the blowout on health: Primary and specialty care visits (preliminary results presented at Community Meeting #7)

• Expanded birth records analysis (preliminary results presented at Community Meeting #3)

• Measurements of indoor and outdoor volatile organic compounds compared to raw national gas measurements taken from the pipes supplying homes (preliminary results presented at Community Meeting #6).

• Chemical transport model exposure fields for benzene and other hazardous air pollutants before, during and after the blowout disaster (preliminary results presented at Community Meeting #5).