Firefighters have more than five times as many cancer causing chemicals in their bodies after tackling a blaze, warns new research.
The toxic chemicals more than quadruple the potential for DNA damage that triggers cancer, according to the study.
And the chemicals get in through their skin – rather than inhalation – meaning firefighters may need to get a decontaminating wash down as soon as they return from a job.
Scientists examined exposure by collecting urine, skin and clothing samples from Ottawa Fire Service personnel in Canada during hundreds of on-shift emergencies over two years.
They found the community heroes are at ever greater risk of developing tumours than previously feared.
Researchers at the University of Ottawa found five times the amount of cancer-causing chemicals on the skin of firefighters – higher than previously thought. The harrowing data was published today, as California’s firefighters battle grueling wildfires (pictured)
Lead researcher Jennifer Keir, a MSc student in the Chemical and Environmental Toxicology programme at Ottawa University, said: ‘We found firefighters have between three and more than five times the amount of PAH metabolites in their urine after a fire compared to before.
‘We also measured mutagenic potency which gives us an indication of the possibility to produce genetic mutations. We found this increased an average fourfold.’
The burning of wood, plastics, furniture, electronics and other building materials releases a large group of highly carcinogenic chemicals called PAHs (polycyclic aromatic hydrocarbons) into the air.
Concern about firefighters’ cancer risk grew after the 9/11 World Trade Center attacks because of their exposure to asbestos and jet fuel.
Since then the hazardous occupation has been linked with multiple myeloma, non-Hodgkin lymphoma, and tumours of the prostate, testicles, brain, bowel and skin.
Based on a study of 30,000 firefighters in three cities, the US National Institute for Occupational Safety and Health reported in 2013 firefighters had higher rates of several kinds of cancer – particularly respiratory, digestive and urinary malignancies.
The risk of lung cancer increased with every fire they fought.
Plastics, foams and coatings in particular create a potentially deadly soup of carcinogens when they burn.
Fire experts say synthetic materials – including TVs and furniture – create hundreds of times more smoke than organic ones.
Flame retardants alone double the amount of smoke and increase toxic gasses 10-fold.
In the study, published in the journal Environmental Science & Technology, researchers at Ottawa University followed 27 male firefighters before and after they responded to emergencies in 2015 and 2016.
On average post-fire levels of PAH metabolites in urine were 2.9 to 5.3 times higher than those before they went out. Mutagenic potency soared 4.3-fold.
The team, led by Dr Jules Blais, used 18 Ottawa Fire Service office workers as a control.
They found a significant link between PAH metabolites – including naphthalene, pyrene, phenanthrene and fluorene – in urine and the levels on the firefighters’ skin.
They said this suggests they are exposed to these harmful chemicals mainly through contact with their skin – rather than breathing them in.
Ms Keir said: ‘It’s important to know how firefighters are absorbing PAHs because we know some are inducing DNA mutations which have been linked to cancer.
‘There’s a relationship between firefighters’ urinary PAH metabolite levels and the levels of PAHs on their skin – which leads us to suspect that dermal contact may be an important route of exposure.’
The researchers conclude skin decontamination immediately after fighting a fire could be one way to help reduce firefighters’ exposure to these potentially cancer-causing compounds.
Captain David Matschke, of Ottawa Fire Service, said: ‘We know about the obvious dangers we face on the job, but this new research gives us definitive proof of the chemicals we are exposed to and the rates of occupational exposure.
‘I’ve been a firefighter for 32 years and I’ve witnessed many of my peers and friends get job-related illnesses.
‘This research into the toxic chemicals in smoke will help, improve our procedures and our equipment meaning reduced job-related illness and longer, healthier lives.’
Six months ago 200 London firefighters tackled the tragic blaze at Grenfell Tower North Kensington, which claimed the lives of more than 80 people.
Public Health England has said levels of PAHs and other toxic chemicals were low.