Hospital visits for smoke inhalation spiked during Boyle Heights warehouse fire

The number of Angelenos who went to the hospital with throat pain and concerns about smoke inhalation spiked as a fire burned through the massive Lineage cold storage warehouse in Boyle Heights this month, The Times has learned.

The blaze burned for eight days beginning June 17 and involved solar panels, insulation foam and other industrial materials.

During that time, more than three times as many people went to emergency departments within 10 miles of the warehouse mentioning the fire or smoke inhalation compared with the two weeks prior, according to data from the Los Angeles County Department of Public Health obtained through a public records request.

The agency also noted a near doubling of patients mentioning throat pain within five miles of the fire June 21 — 1.9 times the baseline levels.

Usually, fewer than 50 people go to the emergency room each day for throat pain, and fewer than 20 people for smoke inhalation, the department said.

The hospitalization data was tracked through the department’s syndromic surveillance project, which monitors trends in what people report when they come to emergency departments in L.A. County, as well as diagnosis codes noted by providers. The system is not as comprehensive as full patient health records, and clinicians may not always include key words about “fire,” “smoke” or other circumstantial information in their diagnoses, the public health department said.

As such, it “cannot capture the true number of [emergency department] visits related to symptoms from the fire and likely underestimates the true burden of fire related symptoms,” the department said.

Perhaps unexpectedly, the department said it did not note a substantial increase in asthma, acute respiratory symptoms or chronic obstructive pulmonary disease-related emergency department visits during the fire.

But even these preliminary findings are concerning, experts said. The fire is believed to have started on the solar array on the roof of the 500,000 square-foot building, which housed 85 million pounds of frozen food. It then reached an ammonia line, prompting two brief shelter-in-place orders for nearby residents.

Over the next week, the fire continued to burn through dense insulation foam within the building’s walls and other unknown industrial materials, blanketing much of L.A. in acrid smoke. Residents in downtown L.A., northeast L.A., Burbank, the San Gabriel Valley and many other parts of the city and county reported seeing and smelling the fumes.

The South Coast Air Quality Management District issued multiple warnings about unhealthy levels of PM 2.5, or fine particulate matter. The city and county opened two smoke respite shelters in the immediate area so that people could breath cleaner air.

It is still unclear what exactly was in the smoke that people breathed in. Industrial fires release far more materials than the burned wood smoke that is emitted during wildfires.

“The makeup of the smoke can include toxic chemicals, fine particles and other serious risks to lung health depending on fire conditions and what is burned,” Will Barrett, assistant vice president for nationwide clean air policy at the American Lung Assn., said as the fire was burning. Children and elderly people are particularly at risk.

David Eisenman, director of the UCLA Center for Public Health and Disasters, said urban industrial fires also can represent a hazard that standard PM 2.5 warnings don’t always address. Those advisories are “blunt instruments” that don’t adequately capture emissions from burning man-made goods — or convey that the source of pollution may include burning batteries or toxic refrigerants, he said.

The fact that initial numbers don’t show a spike in asthma attacks is “somewhat reassuring,” Eisenman said. But “people may have gone to their primary care doctors, which this would not capture. This data deserves follow up.”

The air district and the U.S. Environmental Protection Agency deployed air monitors to assess particulate matter, airborne toxic metals and other harmful compounds during the early days of the blaze. The air district said it didn’t find significant levels of air toxics during the first two days of the fire, although it did record significantly elevated concentrations of particulate matter within the plume downwind.

Some of the measurements it took with mobile monitors, which are five-minute snapshots, also showed increased bromine and chlorine, which often are found when buildings burn and were at levels “below short-term health-based exposure thresholds,” the air district said. It began continuous PM 2.5. monitoring at two nearby elementary schools on the third day.

The L.A. Fire Department said it detected low-levels of toxic hydrogen fluoride on the second day of the fire, which can be a byproduct of burning lithium-ion batteries.

Lineage, the tenant-operator of the warehouse, said no concentrations of ammonia were detected in the air at any time.

“There’s no doubt this fire has had a huge impact on the local community, and we are committed to showing up in every way we can,” company officials wrote in a statement last week. They said Lineage worked closely with the Fire Department during the blaze and delivered masks, air purifiers and other supplies to the community, and will work to ensure the fastest cleanup possible.

The long-term health effects of the fire and its smoke probably won’t be known unless researchers conduct a follow-up study, said Eisenman of UCLA.

For example, there may have been delayed pulmonary effects from the hydrogen fluoride and burning insulation foam that — when combined with the elevated PM 2.5 levels in a dense urban environment — produced health effects that didn’t show up in the emergency room data.

“They will show up in increased primary care office visits and exacerbations of chronic disease over the next few weeks,” he said. “So from a public health standpoint, this fire is not over.”