The smoke over Los Angeles has ebbed over the past five days as firefighters battle flare-ups at a fire at a cold-storage facility. East of the downtown skyline, what was a thick, black plume is now a diluted gray haze.

But neighbors near the blaze, in the city’s Boyle Heights area, could pay attention to little else. They struggled to breathe. They endured headaches and burning eyes, even indoors. During intense periods of smoke, residents described a dystopian scene, with streets shrouded in darkness and visibility no further than a couple of car lengths.

“It’s been hell,” Consuelo Granadas, 80, said standing outside her home in Boyle Heights on Monday afternoon. “You can’t breathe inside the home. The stink is never-ending.”

Ms. Granadas has stuck it out, she said, because she doesn’t want to leave behind her cat and two dogs.

Two blocks over, in the working-class Latino community of East Los Angeles, Mayra Grijalva, 60, donned a white N-95 mask and sunglasses before stepping outside during the lunch break of her remote job. The smell of smoke managed to seep past the taped door frames of her home.

Ms. Grijalva waited at her gate as a county worker with a clipboard emerged from a car parked in the middle of the street.

“Do you need an air purifier?” the woman asked, and Ms. Grijalva replied yes. The woman handed her a brown box and Ms. Grijalva filled out paperwork. Neighbors across the street stood outside wearing masks, waiting for the workers to make the rounds.

Ms. Grijalva said she had spent more than $600 to stay at a hotel where her pets were allowed. She couldn’t afford another expensive hotel stay, she said, and she was uncomfortable taking her pets to one of the emergency shelters that had opened.

Firefighters have made progress, according to Capt. Jacob Raabe, a spokesman for the Los Angeles Fire Department. Because fire started to reach exterior parts of the warehouse’s thick, insulated walls, firefighters over the weekend were able to begin prying them open and shooting water at critical areas that were previously unreachable.

As of Monday, firefighters were still removing walls and using water cannons and high-pressure hoses, Captain Raabe said.

But around the neighborhood, there were frustrations that an industrial facility as large as the one burning could operate so close to homes.

The roughly 500,000-square-foot building is operated by Lineage, a Michigan-based warehouse company, and was storing about 42,500 tons of frozen food.

Lineage has said it believes the fire started during maintenance on a rooftop solar array. “We know many people living near our facility in Boyle Heights are deeply distraught about the fire that began on June 17, and rightfully so,” the company said in a statement.

The South Coast Air Quality Management District extended a warning about poor air quality into midday Tuesday, and said “very unhealthy” air quality had been measured in Boyle Heights even as conditions had improved elsewhere.

Compared with the “garden-variety” air pollution that lingers in cities, smoke from a fire is likely even more dangerous, said Professor Suzanne Paulson, who teaches in the department of atmospheric and oceanic sciences at the University of California, Los Angeles. And industrial fires can produce particularly potent smoke.

Air quality indexes are “set for kind of what we know well, which is normal urban air pollution,” she said.

“When we have smoke, it’s probably more toxic.”

Some residents said this was the kind of disaster that was to be expected in working-class neighborhoods like Boyle Heights and East Los Angeles. The sidewalks are more dilapidated than those in fancier areas of the sprawling city, and the weeds grow from their cracks a little taller.

In the heavily Latino neighborhood, residents fly both the Mexican and American flags and multiple generations cram inside single-family homes, scraping by to survive in one of the most expensive places in the country.

“It just seems unfair to build commercial buildings in residential areas where people are living where a crisis like this can happen,” said Adrian Rolon.

Mr. Rolon’s family lives next to the burning warehouse and he was concerned about his father, who has health problems. Mr. Rolon said that the smoke had become so unbearable that his brother went to stay with in-laws two hours away.

“A lot of people don’t have the resources to just up and leave,” Mr. Rolon said. “So they stay and they close their windows and pray for the best.”

Georgia Gee contributed research.