Expanded environmental testing began Sunday in the affluent Southern California community of Ladera Ranch after six cases of the rare cancer Ewing sarcoma prompted widespread concern among residents.
Students and researchers from Cal State Fullerton collected samples at three parks in the Orange County community, responding to growing outrage and questions from residents following cases of the rare bone and soft-tissue cancer.
The team is examining the park samples for any possible environmental connection to the cancer cases.
“It’s very difficult to prove causation, and we don’t even know that this is environmental. It could be something else that’s potentially causing childhood cancers, but what we want to do is figure out if there is something in the environment. We can figure out if it’s here,” Cal State Fullerton chemistry professor Daniel Curtis told NBC 4.
University researchers could receive preliminary test results as soon as the end of this week.
The testing comes as Ladera Ranch residents press the homeowners association to halt pesticide spraying.
At a Ladera Ranch Maintenance Corporation meeting last Wednesday, at least 10 residents addressed concerns over pesticide use. Among those who spoke was a mother whose son died of cancer earlier this year.
There is no clear evidence linking pesticides to the disease. Still, the deaths of several young people in the small community from the rare cancer have intensified residents’ fears.
A county-level review conducted in 2024 found no unusual pattern. However, the community said the analysis was limited by the available data and called for a more “focused assessment.”
Ewing sarcoma most often affects young children and teens. It also only accounts for about 1% of childhood cancers, with 225 children being diagnosed per year according to Johns Hopkins.
Despite that, surrounding areas in and around Ladera Ranch have recorded 9 to 12 cases of Ewing and synovial sarcoma, with six reported deaths.
A 23-year-old girl named Lily Dalton died in January while a 17-year-old male named Brody Matteson passed away in March.
People from USC have also agreed to conduct their own research.