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A Shark’s Sounds Are Recorded for What Is Believed to Be the First Time

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A Shark’s Sounds Are Recorded for What Is Believed to Be the First Time

Dolphins whistle. Whales sing. Fish croak, chirp, grunt, hum and growl. But in the chatter of the sea, one voice has been missing — until now.

Sharks have long been seen as the silent killers of the water. But scientists at the University of Auckland in New Zealand recently recorded a rig shark, or Mustelus lenticulatus, making a sharp clicking sound, most likely by snapping its teeth together, according to findings published in the journal Royal Society Open Science on Wednesday. They believe it’s the first time a shark has been recorded actively making noise.

The lead researcher, Carolin Nieder, first heard the sound while she was researching the hearing abilities of sharks. While she was handling one shark, it made a clicking, snapping sound similar to that of an electric spark, she said.

The noise came from a rig shark, a fairly small shark common in the waters around New Zealand that grows to up to five feet and mainly eats crustaceans. It is eaten by bigger shark species — and by New Zealanders, who use it to make fish and chips.

Dr. Nieder was taken aback when she heard the noise.

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Other sea creatures have mechanisms for making sound. Fish, for example, have a swim bladder, a gas-filled sac that is used for buoyancy but can also be used as a kind of drum. Many fish have a muscle that can vibrate the swim bladder in a way similar to a human’s vocal cords, generating sounds.

But sharks “were thought to be silent, unable to actively create sounds,” Dr. Nieder said.

For the study, she and her co-authors observed the behavior of 10 rig sharks housed in tanks equipped with underwater microphones. They found that all 10 sharks would begin to make the clicking noise when they were being moved between tanks or gently held.

On average, the sharks would click nine times in a 20-second interval, and the researchers believe they made the sound by snapping their teeth together.

They did not make the noise when they were feeding or swimming, leading the scientists to believe the clicking was more likely something they did when stressed or startled, rather than as a means of communicating with one another.

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“I think it’s more likely that they would make those noises when they get attacked,” Dr. Nieder said, adding that many other fish snap their teeth or jaws in an attempt to deter or distract predators.

It was unclear whether the sharks could hear the clicks themselves; whether they made the sound in the wild or just in captivity; and whether they made it intentionally or if it was a side effect of their response to being startled, Dr. Nieder said.

Christine Erbe, the director of the Center for Marine Science and Technology at Curtin University in Australia, said that the study expanded on a growing field of research into how marine animals make and hear sounds.

“Once we start looking, we find more and more species that use sound,” she said.

Because of that, it was not surprising to find that sharks can make noise, she said.

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However, she added, “I think it’s significant in the sense that we totally underestimate the communication between animals and their environmental sensing abilities, and therefore also how we can impact them with noise.”

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Nearly half of Pasadena Unified schools have contaminated soil, district finds

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Nearly half of Pasadena Unified schools have contaminated soil, district finds

Eleven of the 23 Pasadena Unified School District schools, where students have been back on campus since January, have contaminated soil after the Eaton fire, the district found.

More than 40% of the schools had lead at levels exceeding the state’s health-based limits for residential soil, and more than 20% had arsenic levels beyond what L.A. County considers acceptable, according to the results released Wednesday.

The district found lead at more than three times the state’s allowable limit of 80 milligrams per kilogram of soil next to Blair High School’s tennis courts and more than double the limit at four elementary schools. Lead, when inhaled through dust or ingested from dirt-covered hands, can cause permanent brain and nerve damage in children, resulting in slowed development and behavioral issues.

Arsenic, a known carcinogen, was found at a concentration of 92 mg/kg at San Rafael Elementary School. The county has used 12 mg/kg as a reference level, based on an estimate of the highest naturally occurring arsenic levels in all of Southern California. The naturally occurring background level of arsenic in Altadena and Pasadena ranges from 4 to 10 mg/kg, according to a 2019 study by the U.S. Geological Survey.

There is no safe exposure level for arsenic or lead.

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“I’m worried about her safety,” said Nicole Maccalla of her daughter, a sixth-grader at Octavia E. Butler Magnet, which is located less than a mile from the Eaton fire burn area. “I would really like to have assurances that she’s physically safe while she’s at school.”

Instead, what she got was a map of the school posted by the district showing lead levels 40% and 70% above the allowable limit in soil samples taken next to the school entrance and near the outdoor lunch tables, respectively.

“If, literally, you’ve got to walk by lead to walk up the steps to school, then how many kids are walking through that with their shoes and then walking into the classroom?” Maccalla said. “It’s not like these are inaccessible areas that are gated off.”

Maccalla made the hard decision to let her daughter return to school in January despite early fears — worrying that the trauma of changing schools directly after the fire would be too much.

Along with other concerned parents, Maccalla has been pushing for both soil and indoor testing for months at school board meetings. It was only after the L.A. County Department of Public Health announced in April that it had found 80% of properties had lead levels exceeding the state’s standards in some areas downwind that the district hired the environmental firm Verdantas to conduct testing at schools.

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“The school board has been very resistant to any request for testing from parents,” she said. “The superintendent kept saying it’s safe.” The parents’ response: “Prove it.”

The district released test results for 33 properties it owns — some with district schools and children’s centers, others with charter and private schools, some rented to nonprofits — that were all largely unscathed by the fires. On the 22 properties with public schools, students have been back in the classroom since late January. The full results with maps for each school can be seen on the school district’s website.

The district stated on its website there was “no indication that students or staff were exposed to hazardous levels of fire-related substances in the soil,” noting that any contamination found was highly localized. (For example, although seven samples at Blair High School identified elevated lead levels, 21 samples did not.)

Health agencies also advised the district that soil covered with grass or cement was unlikely to pose a health risk.

In response to the results, the district stated it would restrict access to contaminated areas, complete follow-up sampling and work on remediation over the summer. No classroom instruction would be affected.

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“We want to be abundantly clear: Safety is not negotiable,” Pasadena Unified School District Supt. Elizabeth Blanco said in a press release. “That’s why we’re moving forward with both urgency and care.”

For Maccalla, it’s too little too late. “I would like to know what their plan is for monitoring the health of the children, given you’ve got kids that have already been playing outside in that soil for four months straight,” she said. “So what’s their health crisis mitigation plan?”

The test results also found high levels of chromium — which, in some chemical configurations, is a carcinogen — on one campus. Another had high levels of a class of contaminants called polycyclic aromatic hydrocarbons, which can cause headaches, coughing, skin irritation and, over long periods of exposure, can come with an increased risk of cancer.

Three of the five properties with the district’s children’s centers also had elevated levels of heavy metals — two with lead, one with arsenic.

When Maccalla — who has spent much of her time after the fire volunteering with the community advocacy group Eaton Fire Residents United — first saw the map of her daughter’s school, she began to formulate a plan to rally volunteers to cover the contaminated areas with mulch and compost before school buses arrive again Monday morning. (That is an expert-approved remediation technique for fire-stricken soil.)

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“If the district is not going to do it, the state’s not going to do it, our county’s not going to do it, our city’s not going to do it,” she said, “well, the citizens will. We absolutely will.”

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California board voted to nix a controversial hazardous waste proposal

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California board voted to nix a controversial hazardous waste proposal

A state environmental oversight board voted unanimously to rescind a controversial proposal that would have permitted California municipal landfills to accept contaminated soil that is currently required to be dumped at sites specifically designated and approved for hazardous waste.

Earlier this year, the California Department of Toxic Substances Control (DTSC) released a draft of its first-ever Hazardous Waste Management Plan, a document intended to guide the state’s strategy on dangerous waste.

The draft plan included a recommendation to weaken California’s disposal rules for contaminated soil — typically the largest segment of hazardous waste produced each year. The potential change would have allowed contaminated soil from heavily polluted sites to be dumped at landfills that were not designed to handle hazardous waste.

Environmental advocates and community members expressed concerns that the rollback could result in toxic dust blowing into communities near local landfills or dangerous chemicals leaching into groundwater. State officials countered by saying that contaminated soil would only go to landfills equipped with liners that would prevent toxic substances from seeping into local aquifers.

At a public meeting on the plan held on Thursday evening, the Board of Environmental Safety — a five-member panel established to provide oversight of DTSC — unanimously voted to remove that recommendation from the state’s draft plan. That followed months of intense scrutiny from residents and environmental groups directed toward the plan. DTSC officials present at the meeting also signaled that they would support the board’s decision to nix the revision.

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“I heard you talk about the pollution burdens you already face,” DTSC deputy director Mandi Bane said to the crowd of a few dozen who had gathered at the department’s offices in Cypress. “The worry that DTSC is taking steps that will endanger your community by making that pollution burden worse, and [the] outrage that these steps will be taken without consultation and discussion. As a public health professional, the stress, the fear, the anger that I heard from folks was very concerning … and I do want to apologize that this plan had that impact.”

Heavily polluting industries have tainted soil across California. More than 560,000 tons of hazardous soil are produced each year in California as environmental regulators endeavor to prevent residents from coming in contact with chemical-laced soil and developers build on land in industrial corridors.

However, the vast majority of this soil is not considered hazardous outside of California. The state has hazardous waste regulations that are more stringent than the federal government and most states in the country.

There are only two waste facilities in California that meet the state’s rigorous guidelines for hazardous materials, both in the San Joaquin Valley. Any hazardous dirt in California must be trucked there, or exported to landfills in neighboring states that rely on the more lenient federal standards.

State officials argued the current rules make it difficult and expensive to dispose of contaminated soil, noting that the average distance such waste is trucked right now is about 440 miles, according to the draft plan.

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Ahead of the board vote, environmental advocates rallied outside of the DTSC offices in Cypress, calling on state officials to uphold California’s hazardous waste standards for contaminated soil. Angela Johnson Meszaros, an attorney with Earthjustice, said the proposal would effectively forgo California’s regulatory authority and rely on the federal environmental rules — at a time when the Trump administration is repealing environmental policy.

“This plan is a travesty, and I’m calling on DTSC to be better than this,” Johnson Meszaros said at Thursday’s meeting. “If we don’t draw the line with this massive deregulatory effort, there is no line. We will be swept up in the insanity we see at the national level.”

The discussion of hazardous waste disposal has been thrust into the public spotlight recently as the U.S. Army Corps of Engineers continues to remove toxic ash and contaminated soil from properties destroyed in the Eaton and Palisades wildfires. Because disaster debris is traditionally considered not hazardous, federal contractors have been hauling this material to several nonhazardous local landfills without testing it.

In response to the federal cleanup plans, residents in unincorporated Agoura and the Granada Hills neighborhood in Los Angeles staged protests near local landfills.

Melissa Bumstead, an environmental advocate and San Fernando Valley resident, urged the Board of Environmental Safety to consider factoring disaster debris into the hazardous waste plan. With climate change fueling increasingly destructive wildfires, this will continue to be an issue for years to come, she said.

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“This is an opportunity, not just with hazardous waste that is manufactured,” Bumstead said, “but also hazardous waste that is created by wildfires on how to create a plan that is going to protect Californians in the future.”

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Months after the fires, how safe is it to swim at L.A.'s beaches?

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Months after the fires, how safe is it to swim at L.A.'s beaches?

It seems like a straightforward question: Do the tons of toxic material the Los Angeles County fires sent spewing into the ocean pose an ongoing threat to human health?

For nearly five months, public agencies, advocacy groups and scientists have analyzed samples of seawater and sand in an attempt to determine whether January’s catastrophe has made it less safe to swim, surf or sunbathe at the region’s famous beaches.

Their collective results point to two broad truths.

The first is that neither government agencies nor privately funded groups have found levels of fire-related contamination in sand or ocean water likely to pose health risks to beachgoers. While visible fire debris still occasionally washes up on shore and should be avoided, public health officials and advocates say, there is little evidence of fire-related toxins high enough to sicken visitors through casual recreational exposure.

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The second is that the unprecedented amount of ecological damage January’s firestorms caused simply dwarfs the tools we have available to measure beach pollution.

The seawater safety testing that informs the county’s beach water quality advisories is designed to look for hazards posed by sewage, not fire debris.

State and federal regulators have clear guidelines on the maximum amount of heavy metals and chemicals that can be in our drinking water before it is deemed unsafe, but no similar standards for how much of this stuff it is safe to be exposed to when swimming.

This lack of preexisting health guidelines has made it hard for public health officials to describe the situation at the coast in simple, declarative terms. That, in turn, has frustrated a public that just wants to know if it’s safe to get back on a surfboard.

“There are no human health standards for recreating in water or on sand that has been contaminated, potentially, by these pollutants … and so there’s no straightforward way to test for contaminants and then [say] this exceeds the risk threshold, or it doesn’t,” said Tracy Quinn, president of the environmental nonprofit Heal the Bay. “And that has presented a lot of challenges.”

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The Palisades and Eaton fires incinerated more than 40,000 acres and countless tons of plastics, electronics, building materials, batteries and other potentially hazardous materials. Because of the region’s geography, much of that toxic ash and residue eventually flushed into the ocean.

County health officials closed several miles of coastline entirely in January and February, citing spiking levels of bacteria caused by destroyed sewage systems and dangerous amounts of hazardous debris clogging up the shore.

In the meantime, the Los Angeles Regional Water Quality Control Board began collecting samples of ocean water to assess contaminant levels.

The board soon had reams of public data for beaches from Las Flores Creek in Malibu to Dockweiler Beach in Playa del Rey, showing results for dozens of different contaminants, including heavy metals, polychlorinated biphenol and polycyclic aromatic hydrocarbons.

But, again, there are no established regulations for how much of these contaminants a surfer or swimmer can be safely exposed to. There also isn’t much historical data with which to compare the current amounts of pollutants such as plasticizers, fire retardants and other modern chemicals to pre-fire conditions.

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As a result, county health officials struggled to translate their findings into recommendations the public could use.

“This is not business as usual with ocean water testing,” said Dr. Nichole Quick, chief medical advisor with the L.A. County Department of Public Health.

County health officials spent hours plugging the numbers into a publicly available Environmental Protection Agency tool that helps evaluate safe environmental exposure levels to various substances. They also invited experts from other agencies to weigh in.

No matter how they ran the numbers, they didn’t see evidence that the levels of contaminants present in January and February would threaten human health.

Heal the Bay tested seawater around the same time. The group found enough lead and other heavy metals in some samples to potentially build up over time in the tissue of marine life, but not high enough to sicken a human swimming in those waters.

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The county now has an online dashboard for post-fire environmental data that includes ocean water testing.
But by the time it went live this spring, many members of the public were already frustrated by the lack of clear-cut answers and the confusing pile of data online, said Eugenia Ermacora, Los Angeles chapter manager for the Surfrider Foundation.

“It creates this anxiety,” she said. “Everybody wants an answer right now: Is it safe? Me too! I’m a surfer. My fins are drying. But we’re trying to be patient at the same time.”

L.A.’s coastal ecosystem is now the subject of a massive real-life science experiment. As in all sweeping studies, it will be a while before clear answers emerge. In the meantime, advocates are hopeful that L.A.’s experience now will help communities respond to disasters in the future.

“This is not the last time we’re going to see an urban megafire in a coastal city. It may not be the last time we see an urban megafire in Los Angeles, and we need to be better prepared,” Quinn of Heal the Bay said. “My hope is that we take the information that we’re learning here and we create protocols and standards for what to do next time.”

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