SEE: New 'Heat Map' of Reported Fridley Cancer Cases

Updated June 17: In the nearly three months since Fridley Patch posted , Fridley Patch users have pinned more than 590 data points. (People clicked the map’s markers to learn about an individual case more than 25,000 times as of June 17.)

This profusion of pins can be difficult to visually take in, so we've used a statistical technique known as kernel density estimation to create a "heat map" of Fridley that highlights the locations where users' reports combined to show greater or lesser incidences of cancer.

You can zoom in on the PDF version of the new "heat map." You can download the JPG version.

The and are both investigating whether environmental causes are partially to blame for .

Plan to watch our in Fridley on Wednesday, June 27, at 6:30 p.m. Central.

We’ve marked on the map four Fridley locations—FMC Corp., Kurt Manufacturing Co., Fridley Commons Park Well Field and the Naval Industrial Reserve Ordnance Plant—included on the EPA’s Superfund National Priorities List (NPL), the agency’s catalogue of the most hazardous of the nation’s hazardous waste sites, along with Boise Cascade/Onan Corp./Medtronics, Inc., a site that was removed from the NPL in 1995.

The Superfund sites are there to provide visual and geographic reference—whether there is any relationship between specific pollution and specific public health problems isn't settled.

(Editor's Note: Kernel density calculations were done using GRASS, an open source mapping package. This map contains anecdotal evidence only.)

In March 2012, the Minnesota Department of Health

Upon further study, the department later and said the still higher-than-average number of cancer cases in Fridley was nothing more than a statistical anomaly.

The new rate puts Fridley's incidence of cancer in a range that's "not unusual," according to MDH cancer epidemiologist John Soler:

"It’s not unusual to find communities that have a rate of cancer five to 10 percent above expected and as many that are five to 10 percent below expected, especially when one of the main cancer types is well above or below average rates."

Soler was specifically alluding to lung cancer, which in Fridley is 30 percent higher than than the Minnesota average. The department —which would skew its overall cancer rate statistics.

“Anoka County is the third highest in the state for lung and bronchus cancer,” Soler said of the revised statistics. “We know what the main cause of lung cancer is, and it’s smoking, and that elevated lung cancer rate drives up the overall cancer rates.

“We also know that Anoka County’s smoking rate is relatively high.”

More than 50 percent of Anoka County residents are current or former smokers, according to a public health survey conducted in 2010.

Dr. Tom Amatruda, a genetic specialist at Minnesota Oncology in Fridley,  that elevated cancer rates in Fridley are likely caused primarily by the popularity of smoking in the city 20 years ago. He also said the higher numbers could be dismissed as statistical variation.

Still, the proximity of the four SuperFund sites to Fridley, along with residents' concerns about other potential links, drew the Brockovich team's interest in investigating the statistics and incidents themselves.

Bob Bowcock, Brockovich's environmental investigator said he had identified several underground “contamination plumes”—the result of pollutants released decades ago by industrial companies—spreading below the streets of Fridley and that the investigation was targeted on analyzing the extent and effect of these plumes.

“There are chemical plumes migrating like clouds of fog underground," Bowcock . "They are moving and they are subject to weather conditions. They’re dynamic, they change, they offgas."

See also:

• Fridley Patch Cancer Concerns Topics Page

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