A biostatistician told Florida jurors Monday that radioactive waste from a former Pratt & Whitney rocket and aerospace testing site had contaminated a nearby Palm Beach County neighborhood and caused a cancer cluster in the area.

In a federal court in West Palm Beach, Dr. Francesca Dominici, a biostatistician at the Harvard T.H. Chan School of Public Health, testified that her conclusion of a causal link between contaminated dirt from the site and the cancer cluster was “one of the most certain conclusions I’ve ever made.”

She said her specialty is “connecting the dots,” which included a statistical significance of pediatric cancer in The Acreage, a rural neighborhood in western Palm Beach County; well-established risk factors for brain cancer that include radiation exposure; and the presence of radioactive materials in The Acreage that can cause these cancers.

“Bringing all of these dots and connecting all of these dots together, I informed my opinion that it’s more likely than not that exposure to environmental contaminants caused the cancer cases diagnosed in The Acreage,” Dominici said.

She said she looked at summaries of data collected by Dr. Marco Kaltofen, a civil engineer who specializes in environmental investigations and testified earlier in the case for the plaintiffs. Kaltofen took numerous samples of the soil and water in The Acreage over the course of several years.

On cross-examination, Pratt & Whitney attorney Sean Gallagher grilled Dominici on the lack of an established biologically plausible pathway for any contamination to get from the soil into the groundwater and subsequently the residents to cause the cancers.

“I don’t need to prove biological plausibility to reach my conclusion,” Dominici said. “I have a multitude of data pointing to the possibility of biological plausibility.”

When confronted with a report from the Florida Department of Environmental Protection, which found no evidence of substantial contamination, she said the agency’s methodology was flawed because when testing the homes that had cases of pediatric cancer, it used other nearby homes to serve as a control group.

She said she disagreed with an assessment by the U.S. Environmental Protection Agency that reached a similar conclusion because it relied on the DEP data and report.

“I don’t have a high degree of confidence in the conclusion because of the wrongness of the other study they conducted,” Dominici said.

The plaintiffs rested their case Monday against Pratt & Whitney, a name that was used by United Technologies Corp. until it merged with Raytheon Co. in April 2020. It is now known as Raytheon Technologies Corp.

Property owners in The Acreage say that dirt contaminated with the radioactive element thorium from a rocket and aerospace testing site was used as the fill dirt to construct the development’s 1.25-acre home sites in the 1990s. That dirt contaminated the area’s water, caused a cluster of pediatric cancers and tanked property values, they allege.

From 2004 until 2009, there were at least 10 confirmed cases of pediatric cancer in The Acreage, enough that the Florida Department of Environmental Protection designated it a pediatric brain cancer cluster in 2010.

In opening statements last week, plaintiffs’ attorney Mara Hatfield told jurors that the Pratt & Whitney site was the subject of a radioactive waste contamination cleanup effort, but that the company did not follow regulations for radioactive waste and did not dispose of it properly. She said that 20 years later, the company had to send workers to try to figure out what exactly was buried in the cement casings there.

“If 20 years after you bury stuff in the radioactive materials yard, you have to send people out there with detectors to try to figure out just what was it that we had burying here in cement casings?” Hatfield said in opening statements. “You are not in compliance if you don’t know what you have.”

Gallagher told jurors in opening statements that there was no evidence Pratt & Whitney caused the cancers.

“It’s fundamentally not possible,” Gallagher said. “And no one testifying for the plaintiffs can or will say otherwise. None of them will say that you can get brain cancer from low levels of material in the soil under your feet or the water, much less anything that might have come from Pratt & Whitney.”

He added that the DEP said there was no way anything from the Pratt & Whitney campus could have gotten into the groundwater at The Acreage several miles away. The DEP’s investigation could not determine any cause of the cancer cases and concluded there was no contamination at The Acreage.