Researchers begin environmental testing in Ladera Ranch after cluster of rare cancer cases

Scientists from California State University, Fullerton, joined by researchers from the University of Southern California, began collecting soil and water samples from three parks in the Ladera Ranch community of Orange County on Sunday. The effort follows the identification of six cases of Ewing sarcoma, a rare bone and soft-tissue cancer, among local children and teenagers, which has raised concerns among residents.

Professor Daniel Curtis, a chemistry professor at Cal State Fullerton, told local media that while establishing causation will be challenging, the team hopes to determine whether any environmental contaminants are present in the area. Test results are expected by the end of the week.

The sampling follows a homeowners-association meeting in which residents voiced worries about pesticide applications in the neighborhood. Although a county-level review earlier this year did not reveal an unusual pattern of cancer, community members have called for a more focused assessment given the limited data.

Ewing sarcoma accounts for roughly 1% of childhood cancers, with about 225 diagnoses nationwide each year, according to Johns Hopkins. In the surrounding region, nine to twelve cases of Ewing and synovial sarcoma have been reported, including the deaths of a 23-year-old woman and a 17-year-old male earlier this year.