UCLA researchers embark on next chapter of Aliso Canyon health study

A group of researchers who are working on the large-scale Aliso Canyon Disaster Health Research Study are moving forward with the probe, looking into the impact of the disastrous 2015 gas leak on the human body.

Over the next six months, a UCLA team will continue collecting a massive amount of data that will help dozens of scientists and researchers investigate how residents have been impacted by the Aliso Canyon gas leak near Porter Ranch that went on for four months, forcing thousands of families to evacuate their homes.

The gas leak began in October 2015 and was discovered by Southern California Gas Co. workers who noticed a methane leak rising from an 8,750-foot deep well named SS 25.

The blowout eventually became the largest gas leak in U.S. history, emitting more than 110,000 metric tons of methane and other chemicals into the air and covering nearby schools, cars and playgrounds with oily spots.

In a recent phone interview, Honghu Liu, chair of the section of public and population health at the UCLA School of Dentistry, and a professor at Fielding School and David Geffen School of Medicine at UCLA, said, “We’ve already done an extensive evaluation and determined the affected area, which is within five to six miles southward from well SS-25 where the disaster occurred.”

Researchers will soon begin recruiting residents from the communities affected by the gas leak for the next part of the Aliso Canyon Disaster Health Research Study, including a resident health survey and clinical assessments. The area has between 55,000 and 60,000 households, according to Liu.

The online resident health survey will ask participants to answer questions about their health, social demographics, age, income, employment status and the size of their household. Participants must be at least 18 years old, reside within a 5-mile radius of the Aliso Canyon’s capped well, and live near Aliso Canyon from October 2015 to February 2016.

Liu said his team will select 2,000 participants for the survey. Nearly 1,400 of them will be chosen from the affected area within the 5-mile radius of the broken well. The rest of the participants, or 600 residents, will be from a comparison community outside the affected area.

Another important part of data collection is a clinical assessment. Researchers will randomly select 600 residents from the pool of 2,000 residents who participated in the resident health survey. Out of the 600 residents, 400 will be from the affected area and 200 from a comparison community, Liu said.

The clinical assessment study will include lab tests, and screening of heart rate, blood pressure, body temperature and body mass index, according to Liu. Researchers will also conduct cognitive and neurological screening, measure lung function, and look at their lung capacity. They will collect blood samples to test blood-related diseases and liver and kidney functions.

Those tests, Liu said, will also allow his team to potentially identify thousands of chemicals in the human body, including various pollutants.

The question of which chemicals were released during the four-month gas leak has been a pressing issue since SoCalGas refused to release that information to the public.

A 2018 report by the California Council on Science and Technology revealed that all air quality monitoring missed the first days of the blowout — when residents were possibly exposed to the highest concentrations of emissions.

“Only 36% of chemicals reportedly emitted from Aliso Canyon were monitored for, during, or after the 2015 Aliso Canyon gas leak,” according to the California Council on Science and Technology report.

While residents demanded to know what chemicals they were exposed to during the months-long leak, public officials said SoCalGas was not legally compelled to share that information with the public.

Researchers have been collecting data on the Aliso Canyon facility, its production and the impact on the environment, Liu said. He noted that his team can continue with the study without having a specific list of chemicals released during the leak, “but it will provide insight if we do have it.”

Liu said a long list of potential chemicals could remain in people’s bodies several years after being exposed to the gas leak. The comprehensive analysis would help find evidence of those chemicals in residents’ bodies.

Craig Galanti, a Porter Ranch resident and a former member of a community advisory group formed to advise the health study, has been advocating for years for a clinical assessment.

“We were furious because in the scope of the project (officials at the Los Angeles County Department of Public Health) didn’t mandate the clinical evaluations,” Galanti said. “But we said it has to be mandatory.”

Earlier this year, UCLA researchers discovered that pregnant women who lived near Aliso Canyon during and after its 2015 blowout had a higher chance of premature births and low-weight newborns compared to women from other communities. Women who lived near the facility had a 50% higher chance of having babies with low birthweights than mothers in other Los Angeles County communities, according to their findings released in February.

Patty Glueck, a Porter Ranch resident, co-founder of the Aliso Moms Alliance and former member of the community advisory group, said she was hopeful that the study would reveal the full impact of the blowout on residents’ health.

“We’ve always advocated for the clinical study,” she said. “It is a must.”

Eventually, all the data collected for the resident health survey and clinical assessments will be combined with cancer register data and other statistics in a giant database, Liu said, so researchers can evaluate the impact of the blowout on residents’ physical and mental health.

The UCLA team expects to host the next community meeting and discuss the study updates in the fall.