In late 2017, staffers at Walled Lake Central High School complained to state health officials of a possible cancer scare in their building.

Employees kept getting sore throats and experienced a tingling sensation in their tongues. The symptoms worsened as the school week progressed, according to complaints obtained by the Free Press.

One complaint said 10 staffers had been diagnosed "in the past eight years," while a second complaint put the figure at nine diagnoses since 2014.

"All fairly young staff and we are concerned about something environmental," the complaint said. "This is about 10% of our staff."

The Michigan Occupational Safety and Health Administration (MIOSHA) inspected the school, which has about 1,600 students. MIOSHA found problems related to storing chemicals in the science labs, fined the district $2,100 and ordered it to make changes. But inspectors couldn't address the larger concern.

"MIOSHA has no regulations that address cancer clusters where multiple employees are diagnosed with a variety of different cancers," Elaine Clapp, safety and health manager for MIOSHA wrote in a response to one of the complaints. She went on to advise the employees to contact their local health department or the national Centers for Disease Control and Prevention to address the cancer concern.

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It appears that no one did. The Oakland County Health division has no reports of a cancer cluster from the staffers or the school district, nor does the State of Michigan.

Health officials asked by the Free Press to comment on available information said that cancer clusters are rare, and it's unlikely that one occurred at the school.

District officials insist they took the concerns seriously, quickly ordering air quality testing at the school and checking as well for radon, a naturally occurring radioactive gas that can cause lung cancer.

"There's no indication that there is any health hazard associated with the school. I mean none," said William Chatfield, director of operations for the district. "In fact, all of the testing and the evidence we've collected frankly, suggests there's not. It's a very safe and healthy environment."

District spokeswoman Judy Evola said the Walled Lake district has been transparent about the problem, but acknowledged that it didn't notify parents about the issue until last week, about a year after the district was cited and after the Free Press raised questions about it.

"It was not a safety concern that we believed was validated," she said. "After all the test results came in, it seemed that the district was within the ratio of these things happening in a regular work environment. As far as telling parents that staff had this, it's a privacy issue."

Cancer cases

Compiling precise data on rates of cancer at the school is difficult, in part because of medical privacy.

"We aren't entitled to know the health history of our employees unless they want to voluntarily submit that to us," Chatfield said. "We don't have any process of collecting that data due to (health information privacy) requirements. The law prevents us from knowing the health history of our employees."

The district did assemble some data that was voluntarily submitted, which showed that since 2011, staffers have been diagnosed with:

3 cases of thyroid cancer

2 cases of breast cancer

1 liver cancer

1 pancreatic cancer

1 pharynx/sinus cancer

1 renal cancer

A fourth staffer was thought to have thyroid cancer, but additional testing proved negative, Chatfield said.

He cautioned that the information was voluntarily submitted and not the result of a review of medical records.

"We haven't confirmed any of these," he said. "This is the data we have, which is the best data available. (It) does not indicate any consistency as to the type of cancer or the location in the building."

The district wouldn't identify the teachers because of privacy rules. The Free Press identified several of the individuals independently, but none would speak on the record about their health. One said that teachers don't want to be seen as critical of the district, which still provides their medical coverage.

The school has about 88 teachers currently. Over the past eight years, approximately 200 have worked in the building, according to Chatfield, who added that the school has about the same level of absenteeism as other buildings in the district.

"We do chart the absenteeism," Evola said. "There hasn't been any difference, any fluctuation, any change over the years. We know our employees and we care about them."

The school has about 1,600 students, or 400 per grade level. Over eight years, more than 3,200 would have attended the school. Evola said the district isn't aware of any high rates of student illnesses.

Latency periods

Cancer experts are skeptical about whether the situation at Central warrants a study for a possible cancer cluster.

"I think the common thing that people forget is that cancer is 150 different diseases and we lump them all together," said Dr. Kenneth Rosenman, chief of the Division of Occupational and Environmental Medicine at Michigan State University. "About 40% of us get cancer in our lifetimes. You can't lump them all together."

Rosenman discounts the chemical storage problems as possible causes.

"If you went to most schools in state, many of them are probably not storing their chemicals properly," Rosenman said.

Rosenman said every cancer takes time to develop, what researchers call a latency period.

For example, someone who starts smoking in their teens may not develop lung cancer until their 50s. In general, leukemia-type cancers have the shortest latency period, about five years, Rosenman said. So if a teacher is diagnosed shortly after arriving at a school, it's unlikely the school is the problem.

"It's not what happened in the past five years," Rosenman said. "Other than the leukemias, we're talking about 10 years."

Chatfield, citing the information submitted voluntarily, said some of the teachers were diagnosed with cancer the year they arrived at the school or the year after. At least one had a pre-existing condition.

The teacher who was diagnosed with pancreatic cancer in 2014 had been teaching there since 1999, enough time to cover a latency period, but there's no proof the building was the issue, Chatfield said.

"The correlation is random at best," he said.

Those kinds of factors argue against a cancer cluster or even the benefit of searching for one, Rosenman said.

"Most these types of situations do not turn out to provide useful information," Rosenman said.

State health officials say that they receive about two calls per month asking them to review cancer cases in a specific area and they look for warning to signs that might warrant a closer look.

"If the concern is over an apparently larger-than-expected number of the same type of cancer, especially if it's a rare type of cancer," said Laura Abington, an epidemiologist with the Michigan Department of Health and Human Services, who conducts cancer cluster reviews. "Or if it’s a certain type of cancer that's not normally identified in a certain type of group. An example of that might be a group of children getting a type of cancer that that doesn't normally appear in children or an unusually high number of breast cancer (cases) in men."

Abington said she always begins her investigations with questions about how long the individual has lived or worked in a certain place, what types of cancer have been diagnosed, what are the known causes of those kinds of cancers.

"A single chemical or an environmental contaminant is unlikely to cause many types of cancer," Abington said. "Usually, a chemical or an environmental contaminate is associated with a particular type of cancer or a maybe a couple different kinds of cancer, but not a whole bunch of different types of cancer."

Identifying a true cancer cluster is rare, Abington said.

"Nationally, according to the Centers for Disease Control and Prevention, about 1 in every 5 of these investigations results in something that meets the definition of a cancer cluster," she said. "But rarely, if ever, outside of an occupational setting, is an association ever found between an environmental contaminant and that particular cancer."

A variety of cancers like the ones at Walled Lake Central are unlikely to be caused on any one contaminant, Abington said, adding that cancer cases fluctuate by time and place.

"Some places are going to have more, some places are going to have less and then, five years later, those places that used to have more now could have less," Abington said.

Abington said all cancer diagnoses are reported to the Michigan Central Cancer Registry, which logs a patient's address, age, gender and race. If people in a specific area appear to have higher rates of cancer, researchers can compare their rates to larger, similar populations at the census tract, ZIP code or county level to look for rates that seem excessive.

The CDC requires five criteria be met before it can identify a group of illnesses as a suspected cancer cluster. The cancers must:

Occur in a greater than expected number than would be found in a similar setting.

Occur in a limited population.

Occur over a period of time.

Involve the same type of cancer or types of cancer scientifically proven to have the same cause.

Be found in a defined geographic area.

"There's a lot of chance and coincidence stuff that happens with cancer rates, too," Abington said. "It's really difficult to say what's causing what type of cancer rate. We can't really use the word cause."

Abington said that researchers typically use the term association, rather than cause.

'Tingling sensation'

So if the cancers are unrelated, why were teachers reporting sore throats and the tingling sensations in their tongues?

The school district could never make a firm connection to the causes, but MIOSHA did find violations that needed addressing, fining the district $2,100 and citing it for:

Failure to have chemical hygiene plan.

Failure to properly train staff on hazards of chemicals in work areas.

Failure to have safety data sheets available for all chemicals.

Ventilation fan in chemical storage room not working properly.

Walking/working spaces in science storage rooms were not kept in orderly condition.

Chatfield acknowledged that school was in violation, but said the district has fixed the problems.

The ventilation problem was the result of an exhaust fan that wasn't working the day the inspectors arrived. It's been fixed, he said. All of the fans are controlled by an energy management system that shuts them off when no one is in the building to save energy.

Chatfield said some of those had to be reprogrammed to run longer, though they don't run 24 hours.

"We attempted to address that, short of having to run these things 24/7," Chatfield said. "When a person comes in on the weekend, they just have to know that they're not going to be on unless they let us know to turn them on."

Chatfield said that teachers can't manually switch on a fan after hours because of the programmed control. They must let building officials know to program the additional time, he said.

Other changes included having work crews add short wood lips to the front of shelves where chemicals are stored to prevent containers from falling or being knocked to the floor accidentally.

When the employees first complained, the district paid a contractor, Arch Environmental, to run tests at the school before it received the notices of violation from MIOSHA.

The company placed about 80 radon detectors throughout the building.

"We didn't have a single result that was above the action level," Chatfield said.

In addition, Arch ran air quality tests, checking for things like carbon dioxide, carbon monoxide, hydrogen sulfide, hydrocarbons, mold and dust. No excessive levels were found.

'Teachers feel safe'

Daryl Szymanski, president of the Walled Lake Education Association, the union that represents the district's teachers, said he knew about the number of cancer cases in the building but said teachers haven't complained to him about it.

"As far as I'm concerned, all of the teachers at Walled Lake Central feel safe," he said. "They feel that the district has responded to any potential illness related to the business."

The biggest challenge for the district from OSHA was developing a chemical hygiene plan to standardize how the school handles chemicals. The district had never done one before and it asked for and received additional time from MIOSHA to develop the plan.

The plan, developed by Arch Environmental, has now been implemented at the district's two other high schools, Western and Northern.

But should the district have alerted parents sooner?

Evola says no, saying the tests didn't show a problem. Tamara Precthel, president of the Parent Teacher Student Association at the school, said she learned of the issue when the district issued a statement earlier this month. She doesn't fault the district for not notifying parents sooner.

"Honestly, that's not a concern of mine," she said. "The problem is that when you share something like that, you're going to have some people riled up. Some of them won't read all of it and it would raise more questions than answers."

She said she has two of her own children in the school and an exchange student who lives with her family who also attends. She isn't worried about the building.

"I think I would have made the same decision," she said. "I wouldn't have shared it."

Contact John Wisely: 313-222-6825 or jwisely@freepress.com. On Twitter @jwisely