A local physician studying the health effects of a massive natural gas leak at Aliso Canyon said Monday he warned the Los Angeles Department of Water and Power that high levels of lithium were present in tap water in the San Fernando Valley.

Dr. Jeffrey Nordella, a physician who practiced in Porter Ranch and who had been testing patients who live near the site of the massive 2015 Aliso Canyon natural gas leak, said he notified the LADWP of the lithium levels on Oct. 12, two days before he presented his findings to the public.

He said he sent them two separate e-mails.

“I gave them the findings,” Nordella said of the LADWP. “I did not hear back from them.”

RELATED STORY: Porter Ranch residents exposed to Aliso Canyon gas leak have uranium, lithium and other chemicals in their bodies, health study shows

Joseph Ramallo, a spokesman for the LADWP, said the agency received the findings, but have not reviewed the lab results or methodologies, which were conducted by Weck Laboratories, Inc., in the City of Industry. But he noted that lithium commonly occurs in water systems in the United States, and is naturally found in earth metal found in soil, rocks, dust and in seawater.

He said if there was concern, the DWP would have alerted residents.

“LADWP conducts extensive water quality testing across the city on a continuous basis and, in fact, conducted additional testing of the water served in the Porter Ranch neighborhood during and after the leak at SoCal Gas’ Aliso Canyon natural gas storage facility,”Ramallo said. “At no time was the water served by LADWP to customers in Porter Ranch unhealthful nor was there evidence of anything unusual or unhealthful found in the water.”

He also said the agency doesn’t test for lithium and is not required to. The state’s Water Resources Control Board’s Division of Drinking Water sets the standard, Ramallo said. He added that lithium was not regulated by the federal Environmental Protection Agency in drinking water and “there is no public health goal, which would be a first step in acknowledging a potential health affect and setting a regulatory limit.”

A request for more information from the Water Resources Control Board was not immediately returned Monday.

Ramallo also said the LADWP does not have any groundwater wells in the Western San Fernando Valley, so its wells that are used for drinking water supply are not in any way impacted by the gas leak.

“The levels he (Nordella) found are levels that you would expect to find in drinking water systems in the US and are not harmful,” Ramallo added. “We would alert our customers if there was a concern with the safety of the water we serve. Drinking water is highly regulated and we are required to notify the public in accordance with state and federal regulations.”

He said the water comes from three sources, including the Colorado River, the State Water Project and the L.A. Aqueduct. It’s possible for the Colorado River’s water to have different elements than the other two sources.

“We have a combination of all three in our water system,” he said.

Nordella’s findings on lithium were unexpected and surfaced while he conducted a health study on patients he followed after the Aliso Canyon natural gas leak.

In that study, he found that urine samples showed elevated levels of styrene and ethylbenzene and hair samples revealed uranium, which can be naturally occurring, but was higher in Porter Ranch residents. That’s when he also noted the lithium. Nordella said the results of the hair samples “were statistically significant when compared to averages in the rest of California as well as the United States” which he added supported evidence of patients’ long-term exposure.

Based on the test results, he decided to have the water tested in Porter Ranch and some other communities.

After looking at 25 homes across the San Fernando Valley and across the city of Los Angeles, lithium levels were higher in Porter Ranch, Chatsworth, and Granada Hills, for example, than in homes in Camarillo, Oak Park, Santa Clarita, Simi Valley, Westlake and South Pasadena, where levels were non-detectable.

“Is lithium unusual? We don’t know where it’s coming from,” Nordella said Monday. “We certainly shouldn’t find it.”

Nordella said the results of the lithium levels came two days before he gave his presentation and that’s when he notified the LADWP. He acknowledged that it’s still unclear what the levels could mean, and may have nothing to do with the natural gas leak.

But he pointed to a recent study from Denmark, which found that while a high level of lithium may help people with dementia, certain levels may also cause memory loss.

Of the thousands of water samples taken from homes, scientists in Denmark found that people who consumed 15 micrograms per liter were 17 percent less likely to have dementia. But those who consumed between 5.1 and 10 micrograms per litre were 22 per cent more likely to have dementia.

Nordella said the findings warrant more investigation because it’s unclear what the levels of lithium have to do with the 100,000 metric tons of methane spewed from one of 115 aged wells above Porter Ranch in 2015. The leak sickened thousands of people and forced them to temporarily leave their homes in the northwestern San Fernando Valley. While the leak was deemed unprecedented, no one can point to past studies or research on the health effects of such an exposure to answer residents’ lingering health questions, Nordella said.

Different patients were exposed to different levels for different times, and it won’t be clear how people are affected unless researchers follow them for at least three to five years, he added.

Nordella also had criticized the Los Angeles County Department of Public Health for not demanding that physicians in the surrounding areas conduct toxicology tests and said that’s why he performed his own tests. Instead, the department focused on air samples and more than a month after the gas leak was capped, tested dust samples inside homes, where officials found evidence of metals that were consistent with those found at the natural gas well that blew out near their neighborhood.

In response on Monday, public health officials said such toxicology reports would not have been useful, based on the characteristics of the event.

“For this reason the Los Angeles County Department of Public Health recommended against their use and recommended, instead, that if the attending physician suspected environmental exposure as the cause of the symptoms, to contact Public Health for further consultation,” according to a statement from the department.

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Health officials also defended the timing of the door-to-door investigation.

“The (public health study) was done to investigate why people were still having symptoms after the sealing of the well, therefore it was done at an appropriate time, and after the necessary planning and resources were acquired to implement it properly.”

The department agreed that a longterm health study should be performed, but officials estimate it would cost $35 million to $40 million to conduct. The Southern California Gas Co., operators of the Aliso Canyon gas fields, agreed to pay $8.5 million earlier including $1 million for an independent health study, to settle a lawsuit filed by air regulators in 2016. Health officials have said that $1 million is not nearly enough.

“Public Health believes it is imperative that the health study be designed and implemented in a manner appropriate to the scale and significance of this event,” according to the agency’s statement. “Public Health also believes that such action would plow new ground in defining the accountability that municipal governments require to ensure resolution to health threats created by the close proximity of hazardous industries to highly populated communities.”

Nordella said Monday that neither the public health department nor local universities have reached out to him regarding his study.

In response his work, U.S. Rep. Brad Sherman, D-Sherman Oaks, said in a statement Monday that the doctor’s findings “only strengthen the need for a long-term health study to be completed by the Los Angeles County Department of Public Health.

“Numerous air and facility tests over the past two years have shown elevated levels of benzene, a known carcinogen,” he added. “We can no longer sit on our hands while the lives of thousands of residents of Porter Ranch are at stake”