For weeks, Lineage Logistics and the Los Angeles Fire Department have said ammonia — the hazardous material that’s key for industrial refrigerators — was quickly cleared from the warehouse fire zone. In the days after the fire, Lineage insisted that no measurable ammonia was detected in the area.
Now, community testing as well as data from Lineage and the Southern California Air Quality Management District show that elevated levels of ammonia were present in neighborhoods near the cold storage warehouse weeks after the fire.
Though air regulators and Lineage note the levels didn’t meet the state threshold requiring action to protect public health, community groups say the findings are alarming. Meanwhile, federal regulators are seeking answers from Lineage to determine what air contaminants were released during the fire. Lineage did not respond to questions from Boyle Heights Beat.
An analysis published Aug. 5 by the Community and Environment Research Lab at UC Irvine and East Yard Communities for Environmental Justice found higher levels of ammonia in streets close to Lineage.
That includes Indiana Street near Union Pacific Avenue, where the highest ammonia levels — 4,300 parts per billion — were detected on Aug. 2, more than a month after the fire was extinguished, through handheld aeroqual monitors that community scientists from East Yard have been using to sample the air.

An analysis published Aug. 5 by the Community and Environment Research Lab at UC Irvine and East Yard Communities for Environmental Justice found higher levels of ammonia in streets close to Lineage. (Courtesy of Jill Johnston)
Experts agree that’s many times higher than what’s considered typical, though the standard for ammonia levels in LA’s air varies.
UC Irvine and East Yard Communities for Environmental Justice classify 4 to 6 parts per billion as typical ammonia levels, a figure that’s also considered the baseline nationwide. To South Coast AQMD, typical background levels of ammonia in LA range up to 36 parts per billion.
The analysis by the Community and Environment Research Lab and UC Irvine also shows that higher-than-normal ammonia levels were also detected from a distance.
About a mile from Lineage, ammonia levels have reached 108 parts per billion, according to publicly available data retrieved from a stationary monitor that South Coast AQMD placed late July at Eastman Avenue Elementary School.
To Jill Johnston, associate professor of environmental and occupational health at UC Irvine, the findings not only show “very high” ammonia concentrations closer to the facility, but also how “these chemicals are traveling into the nearby neighborhoods.”
The recent data, Johnston said, suggests that the “big source of ammonia” is coming from the rotting food in Lineage. She also pointed to the ammonia used in the facility’s refrigeration system.
This analysis is just a snapshot of the potential air contaminants present near Lineage, said Johnston, an exposure scientist and environmental epidemiologist.
“In some ways it confirms what people have been experiencing for the last seven weeks … That they’re breathing poor air quality and subject to foul odors, and that we continue to see impacts on local air quality, even seven weeks into this process,” Johnston said.

The U.S. Centers for Disease Control and Prevention, according to its website, said normal amounts of ammonia in the environment do not cause health effects in humans. However, the agency noted that exposure to high levels of ammonia “may hurt your skin, eyes, throat, and lungs and cause coughing and burns. Lung damage and death may occur after exposure to very high levels of ammonia.”
In a statement, South Coast AQMD said it has seen “some levels of ammonia” that were elevated above LA background levels at the Eastman Elementary monitor and from roaming ammonia measurements. South Coast AQMD declined to comment on the air sensors being used to take ammonia measurements.
However, the agency noted, California’s short-term health benchmark — the level of ammonia a person could inhale continuously for one hour without adverse health effects — is 4,500 parts per billion. Despite elevated levels recorded near Lineage, “they do not exceed the State’s short term health standards,” South Coast AQMD said.
“We understand that the situation is dynamic and conditions are changing, particularly with the heat and the decomposing materials that have potential to offgas. We continue to monitor the situation closely,” the agency added.
These findings come in the heels of a letter that the Environmental Protection Agency sent to Lineage on Aug. 3, ordering the company to detail the “specific substances,” including “all air contaminants” that were released during the time of the fire.
“The EPA is aware of a potential hazardous substance release event at the Lineage Logistics,” according to the letter. The agency did not state which substance and gave Lineage 14 days to provide them with the information.
Lineage, which has conducted air monitoring near the warehouse since June 23, said it has not identified chemical concentrations “above health-based action levels.” After on June 19 saying it had not detected “measureable” amounts of ammonia, on Aug. 8, the company acknowledged on its website that “short-lasting ammonia detections” were observed at northern and eastern portions of the fire site. Lineage detected a peak of ammonia at 1,000 parts per billion.

mark! Lopez with East Yard Communities for Environmental Justice pushed back against the thresholds that air regulators are relying on to determine what’s safe and unsafe for residents.
“What we’re dealing with is not short-term exposure. We’re not dealing with one hour, two hour, six hour, eight hour. We’re dealing with a lot of folks who are there 24 hours. It’s inappropriate to use the lowest bar for protecting the community,” Lopez said. “They’re using a standard that’s inappropriate for the actual lived experiences of our community.”
Lopez said air regulators shouldn’t normalize the notion that “there’s always elevated levels of pollution in our communities.”
“… What they’re seeing is not alarming, and we’re like, yeah, because you’re not alarmed by environmental racism, and that’s the problem,” Lopez said.