A new study from the University of Ottawa has found that firefighters absorb toxic chemicals from smoke through their skin while on the job.
Published on the Environmental Science & Technology journal’s website on Oct. 18, “Elevated Exposures to Polycyclic Aromatic Hydrocarbons and Other Organic Mutagens in Ottawa Firefighters Participating in Emergency, On-Shift Fire Suppression” detailed the results of a research team’s examinations of Ottawa Fire Services (OFS) members from Jan. 2015 to April 2016.
The report revealed that after fighting fires, urine samples of OFS workers show four times the potential for DNA damage and contain between three and five times more polycyclic aromatic hydrocarbons (PAH), which are harmful chemical compounds often linked to cancer. Examples of common PAH metabolites in firefighters include naphthalene, pyrene, phenanthrene and fluorine.
“We were looking specifically at compounds that are known to be in smoke that could be contributing to health problems,” explained Dr. Jules Blais, a professor of environmental toxicology at the University of Ottawa and the leader of the research team. “We wanted to determine whether it is possible that the exposures that they experience during on-shift fire suppression could be contributing to this.”
The team studied urine samples and skin swabs from 27 male firefighters and 18 office workers before and after their OFS shifts, Dr. Blais added. “If they fought a fire during that shift, we would do sampling after the shift, and we would be able to see how those exposures changed.” The researchers also had firefighters fill out questionnaires on their roles in the fire-suppression event and the size of the fire and smoke.
OFS Captain David Matschke put the study in motion when he contacted the university after seeing an advertisement about research funding by the Ontario Ministry of Labour, who sponsored the report.
“I’d seen lots of previous studies that looked at exposures, but all of them were done with training fires and really didn’t represent what we were truly being exposed to,” said Captain Matschke. “So I felt there was a need to have a look at the real fires we were dealing with and what the new materials were producing for chemicals.”
Captain Matschke called the study results “somewhat surprising and somewhat not.
“We’ve all known for a long time that we’re being exposed to stuff,” he said. “The biggest ‘aha moment’ for us was when we determined that it wasn’t from breathing in stuff; it was more from the chemicals being deposited on our skin.”
The researchers looked for evidence of lung damage in the study subjects, but found no change from before and after fires. “But what we did find,” said Dr. Blais, “was that when we did skin swabs and looked at what was depositing to their skin, and compared that with what we found in their urine, there was a pretty close correlation. So this suggested that dermal exposure, exposure through the skin, is a driving factor.”
For Dr. Blais, the “take-home message” of the study is to find a way to reduce chemical exposure to firefighters’ skin. “There’s good reason to suspect that dermal exposure,” he said, “is important in determining whether a firefighter is exposed to these chemicals.”
“We’ve already submitted to the Ministry of Labour for a follow-on study on the best methods for removal of the toxins. So we’re hoping to get an answer on the funding for that shortly,” said Captain Matschke. “How do we get it off? Or how do we reduce the effects of it?”
“Elevated Exposures to Polycyclic Aromatic Hydrocarbons” is accessible online at http://pubs.acs.org/doi/abs/10.1021/acs.est.7b02850; non-subscribers must pay US$40 for access to the full report for 48 hours.