(FOX 9) - As the Fire Marshal for St. Cloud, one of Phil Schaefer's duties is to investigate the cause of any fire.
He sifts through the still smoldering, charred remains of a fire with the air still thick with soot, to determine whether it's an accident or arson.
"To me, the worst part of the fire is when the fire is out," Schaefer said.
What remains of the burned debris could still be emitting a variety of gases, a toxic soup of carcinogens that hangs in the air.
Schaefer said he always wore some type of protective gear to fire scenes, yet nothing could've prepared him for the news he received in January of 2018.
"The doctor came into the room," Schaefer recalled. "I knew it was bad, he said, ‘I know you have cancer.'"
He was diagnosed with multiple myeloma at 54, a spot on his spine and another on his ribs.
It's the second leading cause of cancer among firefighters.
When Schaefer ran out of sick and vacation time during his treatments, other firefighters donated theirs.
"They have done things they didn't have to do," Schaefer said. "It is great what they did, they know what our family is going through, it's been wonderful, from the chief down to the firefighters."
Schaefer is not alone in his cancer fight.
Dave Gustafson has been with the Golden Valley Fire Department for 28 years. For half that time, he also worked as a supervisor for the Hennepin County Fire Investigation Team.
Doctors diagnosed him with leukemia.
"Because I have family at home, that was my first thought, ‘How am I going to take care of them, how am I going to be here for my kids and wife?'" Gustafson said.
Sean McKenna worked as an arson investigator with Minneapolis police for 22 years. He retired earlier this year, after oncologists discovered his cancer two years ago.
"There's no family history of non-Hodgkin's lymphoma or leukemia in my family, and I think my years on fire scenes is responsible," McKenna told the FOX 9 Investigators. "The tough part of this diagnosis is it never goes away, and it might someday kill you."
GREATER CANCER RISK FOR INVESTIGATORS
Sixty-one percent of all career firefighters have died from cancer, according to a self-reported survey by the International Association of Firefighters.
A study by the Centers for Disease Control found firefighters have a 14% greater chance of dying from cancer than the general public.
Firefighters are at a statistical greater risk for testicular cancer (102%), multiple myeloma (53%), non-Hodgkin lymphoma (51%), skin (39%), brain (32%), prostate (28%), stomach (22%) and colon (21%), according to the Journal of Occupational and Environmental Medicine.
International Association of Arson Investigators' Jeff Pauley said the cancer risk for fire investigators is even greater than it is for firefighters. He helped write a white paper that describes the best practices for cancer prevention when it comes to fire investigators.
"They have generally, for the last 20 years, been less protected," Pauley said. "For so many years, the prevalent thought among fire investigators was once the fire is out everything is good."
Under pressure to get into a scene as soon as the fire is out, he said investigators will often go without breathing apparatus or other protective gear.
"We are at more fires than the average firefighter and we are there longer than the average firefighter, and sadly at this point, less protected," Pauley said.
"Going on to a scene days later and kicking up this soot, it's no longer being consumed by a heat source, and it's toxic," McKenna said. "Many investigations are simply shovel festivals."
CANCER RESEARCH STARTS FOR INVESTIGATORS
Research at the University of Miami and elsewhere is focusing on fine particulate matter, microscopic soot from what's known as incomplete combustion, all the toxins the fire didn't burn.
The Federal Emergency Management Agency provided a grant to the University's Sylvester Comprehensive Cancer Center to study how firefighters get cancer, and now the researchers are expanding the study to include fire investigators.
The study will interview participants and research the impact of fire scenes on them. While looking for a fire cause, investigators will wear silicon wristbands which will capture post fire particles, along with special wipes to collect what gathers on skin. Blood, urine and saliva tests will also be taken before, during and after investigations.
Results are years away.
The Bureau of Alcohol, Tobacco, Firearms and Explosives - which is the only federal agency that investigates fires - is also looking at a cancer link after a number of its fire investigators developed bladder cancer over the last two decades.
The agency has now invested heavily in respirators, monitors and protective clothing.
"The science for firefighters is coming along, unfortunately the science for the post fire environment is next to nothing, we are working to change that, lots of irons in the fire but nothing now," Pauley said.
Until there are answers, Dave Gustafson takes every precaution he can, as do his fellow firefighters in Golden Valley.
He wears breathing equipment when he is inside a fire scene. After his work is finished, he uses a decontamination station, and wipes down his equipment and showers. Back at the station, he quickly showers to get soot off his body, and he has an extra set of turnout gear while his original gear is getting cleaned in a specialized washing machine, known as an extractor.
"If I can keep this from happening to someone else that would mean the world to me," Gustafson said. "In addition, I am a lot more cognizant that, 'Hey I need to be looking out for myself.' Again, it goes back to my family I want to be here for them."
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