LOS ANGELES — Levels of lead and other heavy metals spiked in the coastal waters off Los Angeles after January's fires, raising serious concerns for the long-term health of fish, marine mammals and the marine food chain, according to test results released Thursday by the nonprofit environmental group Heal the Bay.

For human surfers and swimmers, the results were somewhat encouraging. Contaminant levels from sampled water weren't high enough to pose likely health risks to recreational beachgoers.

But tests of seawater collected before and after the heavy rains that came in late January, after the fires abated, identified five heavy metals — beryllium, copper, chromium, nickel and lead — at levels significantly above established safety thresholds for marine life.

Even at relatively low concentrations, these metals can damage cells and disrupt reproduction and other biological processes in sea animals.

The metals also accumulate in the tissues of animals exposed to them, and then make their way up the food chain as those organisms are eaten by larger ones.

"Most of these metals are easy to transfer through the food web and impact humans directly or indirectly, via food or drinking water," said Dimitri Deheyn, a marine biologist at UC San Diego's Scripps Institution of Oceanography.

All are found in dust and rocks, and aren't harmful in the context of those minute, naturally-occurring exposures.

"That is why these elements are dangerous," Deheyn said. "Our body is designed to take them up, but we are usually exposed to only a small amount of it."

On Jan. 24 and Jan. 25 — before the rain that came the following week — Heal the Bay staff collected seawater samples from eight locations along the coastline in or near the Palisades burn scar, in addition to control samples well outside the burn zone at Paradise Cove in Malibu and Malaga Cove in Palos Verdes Estates.

They took additional samples on Jan. 28, after the first major storm in months dropped half an inch of rain on the L.A. basin and flushed debris into the sea.

They tested for 116 pollutants. The vast majority were either not present or detected in only minuscule amounts in almost all the samples collected.

But levels of beryllium, copper, chromium, nickel and lead were two to four times higher than the maximum allowed under California state law at Big Rock Beach in Malibu, where the wreckage of several destroyed houses still lie on the sand.

"That's not surprising as that's where we have burned debris within the high tide line, [where] every minute of every day the ocean is lapping more and more contaminants into the sea," said Heal the Bay Chief Executive Tracy Quinn.

At the Santa Monica Pier and Dockweiler Beach, both of which are south of the burn scar, levels of both lead and chromium were roughly triple California's safety threshold for marine life. At the Santa Monica test location after the rains, the level of beryllium — a metal that is toxic to fish and corals and causes respiratory distress in humans — was more than 10 times the maximum limit allowed.

Further study is needed to determine whether fire-related contaminants are pooling in those areas or if the high levels are coming from another source of pollution, Quinn said.

"We don't recommend that people consume fish that are caught in the Santa Monica Bay right now," Quinn said.

The levels in these first results suggest that more testing is warranted, said Susanne Brander, an associate professor and ecotoxicologist at Oregon State University.

"Anytime there's a large residential wildfire, this is the kind of contamination you're going to see," she said. "I would look at these results and say, OK, we need to test soils, we need to test drinking water."

Quinn noted several limitations in Heal the Bay's data. The samples were collected in late January, and may not be representative of current ocean conditions. There are also no baseline data showing prefire conditions in the same area to which they could compare their samples, because there are no regular testing programs for these contaminants, she said.

The organization also sampled 25 different polycyclic aromatic hydrocarbons, organic compounds that form when oil, wood or garbage burns. The organization expects results in the coming weeks, Quinn said.

January's fires and the heavy rains that followed sent unprecedented amounts of ash, debris and chemical residue coursing into the sea via the L.A. region's massive network of storm drains and concrete-lined rivers.

The Palisades and Eaton fires burned more than 40,000 acres and destroyed at least 12,000 buildings. In the months since they erupted, the remnants of cars, plastics, batteries, household chemicals and other potentially toxic material have continued to wash into the sea and up onto beaches.

"I don't think there's a precedent for this kind of input into the ocean ecosystem," marine biologist Noelle Bowlin said in January.

In addition to fire contamination, California's sea life is also under threat from an outbreak of domoic acid, a neurotoxin released by some marine algae species.

Hundreds of animals have washed up sick or dead along California's southern and central coasts in recent weeks, in the fourth domoic acid event in as many years.

While nutrients such as sulfate and phosphorous that feed harmful algae were among the substances the fires released into the sea, Heal the Bay said it has not found a correlation between fire-related pollution and the outbreak now sickening marine animals.

Understanding all of the effects that heavy metals, chemicals, bacteria and other pollutants released by the fire will have on the marine ecosystem "will take a huge, collaborative effort," said Jenn Cossaboon, a fourth-year student at the UC Davis School of Veterinary Medicine who recently finished a doctorate on endocrine disruption in fish.

"Species at each level of the food chain, from invertebrates to fish, birds, marine mammals and humans, can be affected differently based on their physiology and feeding strategies," she said. "It will be very important to connect each of these pieces of the puzzle to really understand the impacts on the food web."

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