“This was the scariest thing in the world for us, and then we started to realize that it was happening to other families in our city,” said Raso, whose family moved to Stoneham soon after. “We felt like something was happening, but nobody knew what.”
More than two decades later, the state Department of Public Health released a report on Wednesday crediting the The fears of Rasos. The results “strongly suggested” a link between the elevated rates of childhood cancer in Wilmington in the 1990s and prenatal exposure to contaminated water during that time.
Between 1990 and 2000, at least 22 local children contracted cancer. Two of them have died.
“Despite the limitations, including a small sample size and modeled exposure estimates, the study results show an association between childhood cancer and prenatal exposure to NDMA,” DPH officials said in announcing the findings.
In an initial study in 2000, state officials identified an unusual pattern of children with cancer living on the west side of Wilmington. Those findings led the Legislature to fund a larger epidemiological study to determine if they were the result of environmental factors.
In 2003, regulators identified a known carcinogen called North-nitrosodimethylamine, or NDMA, which contaminated the drinking water of one of the city’s aquifers, which was closed. They determined that the contamination came from a large chemical manufacturing plant in the city that had been operated by a number of companies between 1953 and 1986.
The 53-acre site was last purchased by Olin Chemical Co. in 1980 and is now managed by the Environmental Protection Agency as a Superfund site. The EPA recently issued a $ 48 million plan to clean up the area.
The study also investigated whether the cancers were associated with exposure to trichlorethylene, or TCE, a solvent also present in water that has been linked to cancer. DPH officials said the results were “statistically significant.”
“The results remained constant even after statistical adjustment for other possible cancer risk factors, such as exposures from maternal pregnancy, domestic and occupational exposures, family history of cancer, and childhood medical history,” health officials said in a statement. “There was no evidence of an increased chance of cancer for children who were exposed to NDMA or TCE during childhood.”
Officials at Olin Chemical Co. said in a statement that they were “in the process of reviewing the study and its findings.”
“Olin was not asked to participate or contribute information to the Massachusetts Department of Public Health or others in connection with the study,” said Ed Kral, a company spokesman. “We continue to work in cooperation with and under the direct supervision of the US EPA and the Massachusetts Department of Environmental Protection to investigate and remediate the Wilmington site.”
Kathleen Barry, a spokeswoman for 18 of the families whose children were diagnosed with cancer in the 1990s, said many of the parents were relieved to finally have answers.
“We are all struggling to do something good with such a bad situation,” he said.
Many families were surprised to learn that the the exposure was prenatal.
“They were shocked by this,” he said. “Although they expected the link, they were stunned by the way the department found out.”
The study required researchers to develop computer models and reconstruct the historical concentrations of the chemicals in the homes of each study participant, which is part of the reason it took so long to complete, DPH officials said. The study was scheduled to be published last year, but the pandemic delayed it.
Only two cases of childhood cancer were diagnosed in Wilmington between 1982 and 1989, probably before the chemicals entered the aquifer, the report found. The 22 cases from the 1990s included eight cases of leukemia and three lymphomas. Since 2001, local childhood cancer incidence has returned to expected rates, about one case per year, state officials said.
In the study, the researchers wrote that while the “presence of these contaminants cannot definitively explain the pattern of childhood / adolescent cancer,” the risks of exposure offer “what we believe is a plausible explanation.”
Barry said the families are unlikely to file a lawsuit against Olin, who has already set up a trust to pay for their children’s health care, education and other financial needs.
It was unclear how the city would respond, given the long-term loss of a vital and lucrative aquifer that provided about 3.5 million gallons of drinking water a day to the city’s 22,000 residents.
“I wish to express my condolences to the families,” said Jeffrey M. Hull, the City Manager. “There is no more terrifying diagnosis for anyone, and especially parents, than knowing that their child has cancer.”
He said city officials are taking the findings “very seriously” and will consult with an environmental consultant to determine their next steps.
When asked if the city would sue Olin, Hull said: “I cannot offer further comment pending a detailed review of the study.”
He said the city’s water supply is now safe, meets state and federal requirements, and undergoes regular testing.
“Providing residents and businesses with safe and potable water is a central priority of the city,” he said.
Local environmental advocates, who have long expressed frustration at the city’s inaction, said they thought residents deserved to be compensated.
“That aquifer was a revenue generator for the city and that resource has been damaged, possibly irreparably,” said Martha Stevenson, chair of the Wilmington Environmental Restoration Committee.
He said many local residents felt vindicated on the merit of their suspicions.
“It was really frustrating to have to wait so long and have families in limbo for two decades,” Stevenson said.
For the Rasos, whose daughter Nicole is now a healthy 24-year-old preschool teacher, the report left them with mixed emotions.
“We are satisfied to be validated, but it does not make us feel better that our children were sick and some of them died,” said Raso. “There is definitely some lingering anger.”