This week, the Environmental Protection Agency outlined its plans to assess at least four sites in West Salem for hazardous contamination.
Hundreds of West Salem residents signed petitions asking the EPA to find out if environmental toxins are causing a sudden rise in osteosarcoma among young people in the community.
Officials have confirmed five cases of the rare bone cancer in the West Salem area in the past several years. Three people have died from the disease and two more cases have been reported.
At two public meetings the EPA held on the issue this week, some community members were clearly frustrated: Why can't officials confirm a cancer cluster and find a cause?
The answer is complicated.
State epidemiologist Katrina Hedberg explained that the statistics the Oregon Health Authority uses to measure cancer rates across Oregon don't offer much help in this case.
According to the Centers for Disease Control, a cancer cluster is a greater than expected number of cancer cases among a group of people in a geographic area over a period of time. The parameters you set for the group of people, the geographic area and the period of time are all really important to confirming a cancer cluster, Hedberg said.
And if you try to apply them to a relatively small community such as West Salem, the "expected number" of cancer cases becomes statistically unreliable.
“We’re not saying it isn’t a cancer cluster,” said Hedberg. “The data can’t tell you whether this is a cancer cluster or not. This is not a place where the numbers and statistics are all that helpful. It’s not hard to crunch the numbers, but it’s hard to make sure our numbers are meaningful.”
But regardless of whether they can confirm a cancer cluster, the result is effectively the same: The EPA is going to take a close look at the parts of the community cancer patients had in common: Walker Middle School, West Salem High School, Orchard Heights Park and a local ball field at 7th and Patterson.
The EPA will start with a paper trail – property records, land use history and any reports of contamination at the four sites. The agency will be looking for a wide array contaminants that could be making people sick, said Tony Barber, director of the Oregon office for the EPA. And if there's evidence of possible toxins, they will start testing.
"We can talk about numbers, but we’re very focused on finding anything out there in your community that might hurt anybody," Barber told the community Tuesday. "If it’s one person and that person is in your family it’s a big deal. We don’t want people to get sick if they don’t have to.”
West Salem residents have lots of questions: Could it be radon? Have the homes of the cancer patients been tested? Could the local machine shop have spread some kind of toxin? What about flooding from the Willamette River? Is fluoride in the city's water to blame? Shouldn't the city shut down the local parks until they've been tested?
Research hasn't confirmed many links between environmental contaminants and osteosarcoma, health officials say. A high dose of radiation among patients who have been previously treated for cancer has shown to increase the risk of getting the decease, and exposure to radioactive elements has been linked to increased risk. Some research suggests a connection between fluoride and osteosarcoma, but some does not.
“What chemical might it be? We have very little to go on,” said Jae Douglas, an environmental health and research manager at OHA. "Radon is in lots of communities and we’re not seeing osteosarcoma in lots of communities."
Kenji Sugahara, chair of the West Salem Neighborhood Association, said he has a young daughter and wants to make sure it’s safe to take her to the local parks. He said it may be a difficult to find the answers the community wants, but getting the EPA to take action is a start.
“We have the right people in the room who can move this forward,” he said.