BACKGROUND: A natural gas leak occurred from October 23, 2015 to February 18, 2016 at the Southern California Gas (SoCalGas) Aliso Canyon Storage facility. Air samples collected during the leak showed elevated levels of methane and benzene in the affected areas. 5,000 households relocated. About 9,000 Veterans in Porter Ranch and surrounding areas were directly affected by the leak. The impact of the leak on the health of Veterans and their consequent use of health services related to the exposure has not been assessed. We examined outpatient records of VA users from Los Angeles and Ventura Counties from July 2015 to July 2016, investigating potential impacts of the PR gas leak on Veterans’ health.
METHODS: Based on Zip Codes, all patients were divided into three groups: Porter Ranch (PR) Group (14 Zip Codes), San Fernando Valley (SFV) (parts of LA and Ventura Counties surrounding Porter Ranch), and the rest of LA and Ventura Counties (GLA). Total number of visits per month per group was assessed for all three groups. Number and percentage of total visits per month per group was assessed for symptoms consistent with natural gas exposure. We investigated visits to primary care, otolaryngologists, pulmonologists, gastroenterologists, and dermatologists.
RESULTS: There were 4,093,510 outpatient records; 125,681 unique Veteran VA users. 2,371 were Porter Ranch (PR) residents, 18,886 lived in San Fernando Valley (SFV), and 104,401 resided in other areas (GLA). For the PR group, we observed an immediate increase in the number of primary care visits during October-November 2015 compared to SFV and GLA groups. For primary care visits, the percentages of total monthly encounters were: 25% (PR), 23% (SFV), and 19% (GLA). For ENTs, the percentages were 0.7% (PR), 0.6% (SFV), and 0.5% (GLA). Additionally we observed an increase in pulmonology visits in April 2016 (2.8% (PR), 1.3% (SFV), and 0.9% (GLA), which can be indicative of a long-term effect of exposure to natural gas for the residents living in the PR affected areas.
CONCLUSIONS: Outpatient visits to primary care providers, ENTs, and pulmonology specialists increased in the PR gas leak affected areas. Further monitoring and more detailed analysis of outpatient and inpatient visits, including provider notes, is recommended to further determine the short and longer-term effect of the PR gas leak on the health of Veterans living in the impacted gas leak area as it might have implications related to health needs and health services delivery.