Riot Aftermath : Experts Warn of Dangers That Might Be in Rubble : Toxic substances: Officials say at least half of the more than 5,000 burned buildings contained asbestos. Cleanup crews need to be careful.

Calling on residents to stay out of charred buildings and to protect themselves against potentially hazardous asbestos and other toxic substances, environmental officials on Tuesday began a painful assessment of the potential dangers lingering in the burned-out rubble of the Los Angeles riots.

Officials estimated at least half of the more than 5,000 buildings burned in the mayhem contained asbestos.

Well before fire and air pollution inspectors were allowed by their superiors to enter riot-torn neighborhoods, cleanup volunteers had begun sifting through the asbestos-laden debris. Like the scavengers combing the wreckage for valuables, they did not take precautions. A county fire official estimated that 100 of the burned-out structures may still contain potentially troublesome quantities of other toxic chemicals as well.

In the aftermath of the fires, storm drains dumped soot, ashes and other toxic materials into the sea. As of Tuesday, soot and debris were still washing up on the sands of Venice Beach.

To cope with the crisis, about 50 federal, state, regional, county and local environmental and health and safety officials hastily convened a meeting Tuesday and divided themselves into teams to determine how best to avert and alleviate environmental dangers without hampering the cleanup and rebuilding of the city.

“This tremendous tragedy has environmental consequences for air, water, waste--every area,” California Environmental Secretary James M. Strock told the City Hall gathering.

In a three-hour session, the officials, representing a broad spectrum of agencies, mapped out an agenda for the next several days that will include:

* Compiling an inventory of fire-damaged buildings that contained toxic materials and cordoning off those that pose a public threat.

* Redirecting volunteers away from rubble cleanup, which could be dangerous, to graffiti removal, community help groups and tree-planting.

* Setting bait for disease-carrying rats and other vermin in partially destroyed or looted buildings.

* Identifying which landfills can take the rubble and classifying which kinds of debris are hazardous.

* Determining who will pay for hazardous waste cleanups.

* Ensuring that debris is not swept into storm drains, where it could pollute local waterways.

Fire officials said they were hampered in identifying which burned-out buildings contained toxic chemicals because many had been so thoroughly destroyed that addresses were obliterated.

Fire departments keep lists of companies that use or store hazardous materials, but officials in many cases are having to go to assessors’ maps before they can match addresses against the list.

Initial inspections, however, provided some good news. Most of the businesses burned were commercial, not industries that use toxic materials in their manufacturing.

Of the first 80 sites surveyed by city fire officials, only one contained significant quantities of hazardous substances.

“It doesn’t look as bleak as you would think,” said Battalion Chief Lawrence Krokes.

County fire officials inspected 23 sites Tuesday and found hazardous wastes in 20% of them.

“We’re not going to find a great big walking disaster out there,” said John M. Cummings, deputy chief of the Los Angeles County Fire Department. “What we are going to find is a whole bunch of little disasters.”

Officials expressed more concern about asbestos in the rubble. James M. Lents, executive officer of the South Coast Air Quality Management District, said any building more than 20 years old probably contains the hazardous material.

Several officials pleaded for quick removal of potentially asbestos-laden rubble from residential communities, while others argued over which dumps were licensed to take the waste.

“Your greatest hazard is leaving it there in the community where little kids can go play in it,” said Felicia Marcus, president of the city’s Board of Public Works.

Deputy Los Angeles City Atty. Vince Sato said people should not be alarmed by the general level of dust in the air.

“Off-site migration of asbestos in debris and soot is not such a threat that there’s a need to warn people,” he said.

Until its hazards were recognized, asbestos had been widely used as building insulation and for fire protection. Many researchers believe that inhaling asbestos fibers increases the risk of cancer.

In addition to the asbestos danger, AQMD inspectors surveying riot-torn neighborhoods over the weekend also said they saw people moving leaky electrical transformers, which contain potentially carcinogenic PCBs or polychlorinated biphenyls.

“In general, people should stay out of buildings that have been torn down,” a district spokesman said, “and leave demolishing to licensed contractors.”

Laurance Israel, an AQMD inspector, said in an interview that he saw unprotected cleanup crews inside a dozen buildings in South Los Angeles that were likely to contain exposed asbestos.

Near Western and Slauson avenues, he watched about 100 volunteers, organized by a gang services worker, slog through debris, dust and soot of a burned-out market.

What was left standing was brick, an indication that the building had been old enough to be veined with asbestos materials. The ceiling was gone--either destroyed or left in charred pieces on the ground. The workers were removing and separating metal.

“Nobody was wearing any type of protective clothing,” Israel said.

As the crew took ceiling materials and flooring over to dumpsters, “they were creating a bunch of dust in that area,” he said. “It was getting in people’s eyes. Nobody was focused on what potential hazards there were.”

Asbestos “is very resistant to heat and in a fire, it is not destroyed, it’s just exposed,” he said.

Cleanup coordinators passed out paper dust masks, but they do not protect against asbestos, Israel said. The most effective measure is to wet down the debris to keep the flakes from becoming airborne, when they are most dangerous in the immediate vicinity.

Among the charred remains Israel also saw remnants of dry cleaners. Dry-cleaning solvent, perchloroethylene, last year was declared a toxic air contaminant by the California Air Resources Board, which means it is regulated for its cancer-causing property.

“That’s what was burning,” Israel said.

Environmentalists have been conducting their own damage assessments. Brenda Goeden, of Heal the Bay, said she regularly checks the state of Ballona Creek, which runs into the sea near Marina del Rey, as she drives between her Westchester home and her Santa Monica office. Last Tuesday, before the riots, she spied a sea lion catching fish at the mouth of the creek. On Thursday, she said, the water ran thick and charcoal-gray.

On Saturday, Goeden understood why. Joining cleanup efforts in South Los Angeles, she watched volunteers sweep pools of polluted water from the wreckage into the street. From there the water traveled into storm drains, which channeled it to Santa Monica Bay.

“It’s hardly a priority right now for anyone to see what the impacts are on marine life, and we understand that . . ., “ said Mark Gold, staff scientist at Heal the Bay. “All we can say is, don’t swim near Ballona Creek outfall.”