Rare Pediatric Cancers Persist 63 Years After Nuclear Accident

Neil Osterweil

March 12, 2022

April 22, 2022 — Editor's note: This article has been updated to include an interview with Thomas Mack, MD, MPH, former director of the Los Angeles County Cancer Surveillance Program, who contends that there is insufficient evidence to support a direct link between the 1959 reactor accident and recent incident cancers.

March 11, 2022 — Chernobyl. Fukushima. Three Mile Island. 

The world knows these names all too well because of accidents there: complete or partial meltdowns of nuclear reactors that released massive amounts of cancer-causing radiation into the air, soil, and water. 

The Santa Susana Field Lab (SSFL) is far less well-known, but no less infamous for what took place at this former rocket engine and nuclear energy test site just 28 miles northwest of downtown Los Angeles. 

In July 1959, an accident involving one of 10 experimental nuclear reactors at the SSFL site released a cloud of harmful radiation and toxic chemicals over the surrounding area, including Simi Valley, San Gabriel Valley, Chatsworth, and Canoga Park. The small reactor had no containment vessel. 

This accident resulted in a release of radioactive iodine estimated to be as much as 250 times that of the partial meltdown that would occur 2 decades later at Three Mile Island, a much larger commercial reactor that had a containment vessel.

Six decades later, hundreds of potentially carcinogenic chemicals remain in the surrounding environment. And local children are being diagnosed with rare cancers at a rate that far outpaces what experts would predict. 

Decades-Long Cover-Up  

In 1959, the public knew nothing about what had happened at the site.

According to John Pace, then an employee at SSFL, the accident was covered up. Pace recounted the cover-up in the documentary In the Dark of the Valley, which first aired in November 2021 on MSNBC.

In fact, the accident at SSFL remained under wraps for 2 decades, according to Daniel Hirsch, former director of the Program on Environmental and Nuclear Policy at the University of California, Santa Cruz, and now president of Committee to Bridge the Gap, a nuclear policy nongovernmental organization.

“Students working with me while I was teaching at UCLA in 1979 uncovered these Atomic Energy Commission reports from Atomics International,” he said in an interview. “We had to order the documents from the annex to the UCLA Engineering Library. They were stored offsite, and it took a few days, and when we got them, we opened them up, and there were these fold-out photographs of the fuel [rods]. As we folded out the photographs further, we saw one photo with an arrow labeled ‘longitudinal cracks,’ and then other arrows showing other kinds of cracks, and then another arrow labeled ‘melted blob.’”

Hirsch and his students found that other accidents had occurred at SSFL, including a fuel fabrication system that leached plutonium, fires in a “hot” lab where irradiated nuclear fuel from around the United States was handled, and open-air burn pits where radioactive and toxic chemical wastes were illegally torched. 

According to the Committee to Bridge the Gap, when the 2,800-acre SSFL site was being developed under the name Rocketdyne by aircraft maker North American Aviation, the area was sparsely populated, with nearly as many grazing animals as people in its hills and valleys. 

North American Aviation later became part of Rockwell International, which in turn sold its aerospace and defense business units to the Boeing Company in 1996. Boeing, now in charge of the site and the cleanup efforts, is doing everything in its power to shirk or diminish its responsibility, Hirsch and other critics say. 

Parents Against SSFL  

Today, more than 150,000 people live within 5 miles of SSFL, and more than half a million live within 10 miles. 

Melissa Bumstead is one of those residents. She and her family live 3.7 miles from the Santa Susana site. When her toddler Grace was diagnosed with a rare form of leukemiain 2014, doctors told Bumstead there were no known links between her daughter’s cancer and environmental contamination. 

But during Grace’s treatment at Children’s Hospital Los Angeles, her mother began meeting other parents who lived near her and had children facing equally rare cancers. 

Lauren Hammersley, whose daughter Hazel was diagnosed with a rare brain tumor called neuroblastoma at age 2, lived about 10 miles from Bumstead on the other side of a mountain and just over 4 miles from SSFL. 

On her street alone, Bumstead discovered three cases of pediatric cancer, including two children in adjacent homes who had the same rare brain tumor as Hazel Hammersley. 

As Bumstead told Los Angeles National Public Radio station KCRW in 2021, "I started to panic because I knew that childhood cancer is extremely rare. There’s only 15,000 new cases every year out of 72 million children in America. So, the chance of knowing your neighbors, especially at an internationally renowned hospital like Children’s Hospital Los Angeles -- we knew something wasn’t right.” 

After a relapse of her tumor, Hazel died in 2018, a few months after her seventh birthday. 

Cancer Clusters  

Hoping to understand why their kids were getting so sick, Bumstead and the other parents formed a Facebook group. They plotted their homes on Google Maps and found that they all lived within roughly 10 miles of one another. It would take another year for them to realize that the SSFL site was at the center of the circle. 

Once they realized that being close to SSFL could be their common thread, Bumstead and parents in her group began to gradually piece together the story, linking unusual or unexplained illnesses in their families to potential radiation or toxic chemical exposures from the lab. 

"What really convinced me that this was absolutely a problem was when I learned about the epidemiological study by Dr. Hal Morgenstern that found that residents living within 2 miles of the Santa Susana Field Lab actually had a 60% higher cancer incidence rate and that over 1,500 workers have been diagnosed with cancer just from the Santa Susana Field Lab,” she told KCRW. 

In 2015, Bumstead and other parents formed Parents Against Santa Susana Field Lab to hold SSFL site owner Boeing accountable for radiologic and toxic contamination and to ensure that Boeing cleans the site and surrounding areas. The group “seeks to reduce, to the greatest extent possible, the number of local families who have to hear the words, ‘Your child has cancer.’” 

No Longer Quite So Rare  

Morgenstern, now retired from the University of Michigan, declined to be interviewed for this article. But as he and colleagues reported to the CDC’s Agency for Toxic Substances and Disease Registry in 2007, there were strong signs of a link between contamination of the site and cancer. 

The researchers compared cancer rates of adults living within 2 miles and 2-5 miles from SSFL with those of adults living more than 5 miles away, in Ventura and Los Angeles counties. They found that from 1988 through 1995, residents living within 2 miles of SSFL had a 60% higher rate of cancers than the control group. These included cancers of the thyroid, oral and nasal cavities, pharynx, larynx, esophagus, and bladder, as well as blood cancers such as leukemia, lymphoma, and multiple myeloma

In separate studies, the investigators found higher rates of certain cancers among workers at SSFL who were exposed to radiation and to hydrazine, a chemical in rocket fuel. 

In an interview, Saro Armenian, DO, a pediatric hematologist-oncologist who was not involved in the studies, said the 60% increase in cancer incidence, which translated into a 1.6-fold increase in risk, merits more investigation. 

In epidemiologic studies, a 1.6-fold risk is actually a pretty strong signal because typically, most signals that you get are somewhere around 1.1- to 1.2-fold increased risk,” noted Armenian, a specialist in pediatric cancer survivorship and outcomes at City of Hope National Medical Center in Duarte, CA.

However, Thomas Mack, MD, MPH, former director of the Los Angeles County Cancer Surveillance Program, contends that there is insufficient evidence to support a direct link between the 1959 reactor accident and recent incident cancers. Mack is currently a professor of preventive medicine and pathology at the Keck School of Medicine of the University of Southern California in Los Angeles.

“I have evaluated concerns about local excesses of cancer at least 100 times, usually from county residents, but for a while I represented the CDC and the California cancer registry,” Mack said, in response to an emailed request for comment.

“So far I have seen no evidence of carcinogenic radionucleotides or chemical carcinogens from Santa Susana found in any meaningful amount in any nearby community, but if someone has such evidence that would constitute evidence, that needs a response,” Mack added.

Boeing and California  

But Boeing has said problems at SSFL were not responsible for the high cancer rates among children in the community. 

In April 2007, in a statement opposing a bill before the California State Legislature that would compel Boeing to pay for SSFL site cleanup, the company said that “in contrast to the accusations made against The Boeing Company that falsely claim increased cancer rates in the communities surrounding SSFL, a recent study conducted by the University of Michigan School of Public Health just concluded the opposite.” 

But as Morgenstern wrote in 2007 to California state Sen. Joe Simitian, then chair of the Committee on Environmental Quality: “For the period 1996 through 2002, we found that the incidence rate of thyroid cancer was more than 60% greater among residents living within 2 miles of SSFL than for residents living more than 5 miles from SSFL. The magnitude and consistency of the thyroid finding for both periods is especially provocative because of evidence from other studies linking thyroid cancerwith environmental exposures originating at SSFL and found in the surrounding communities.” 

Boeing chose to ignore the results and instead focused on the methods used in the study, where the authors acknowledged that they measured distance from the site rather than environmental exposures and thus could not conclusively link excess cancer rates to exposures arising from SSFL. 

But Morgenstern emphasized the conclusion of the report: “Despite the methodologic limitations of this study, the findings suggest there may be elevated incidence rates of certain cancers near SSFL that have been linked in previous studies with hazardous substances used at Rocketdyne, some of which have been observed or projected to exist offsite.” 

Failure to Come Clean  

In 2008, a law that set standards for cleanup of the site was passed. But the law was overturned in 2014 after a legal challenge by Boeing. 

That left in place a 2007 order of consent between Boeing, NASA, the U.S. Department of Energy, and the California Department of Toxic Substances Control (DTSC) that required cleanup of SSFL to a much less stringent standard.

As of last year, Boeing and DTSC had begun confidential, nonbinding agreements regarding the 2007 order of consent, according to Parents Against SSFL. 

Among the contaminants lingering at the site are radioactive particles, chemical compounds, heavy metals, and polluted water

“In fact, over 300 contaminants of concern have been found at the site, and they are refusing to clean it,” Hirsch said. “This company releases large amounts of carcinogens, and perhaps significant numbers of people get sick with cancer, and the company doesn’t go to prison. They get more federal contracts."


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