A recent study published in the New England Journal of Medicine is making the talk show circuit. The study reports that firefighters have an increased risk of heart attack when fighting a fire. At the firehouse, we called this study a PGIO, a Penetrating Glimpse Into the Obvious. In other words, we already knew this.
The study’s authors hypothesize that the risk of a heart attack increases because of underlying heart disease, compounded by the effects of strenuous exertion at the scene of a fire. The report says “cardiac events during fire suppression may be increased because many firefighters lack adequate physical fitness, have underlying cardiovascular risk factors and have subclinical or clinical heart disease.”
The authors of the recently published study obtained their data from records at FEMA, the International Association of Fire Fighters and the National Fire Protection Association. The study does not state if they interviewed any firefighters or if they went to any fires. I reviewed the credentials of the authors of this study. There were several physicians, an industrial hygienist and a few public health experts. Most were from Harvard.
None were firefighters.
The study did not discuss the true nature of the fire environment. Structural fires have long been known to release more than 100 types of toxic chemicals. Some of these toxins, such as phosgene, are released from the incomplete combustion of the vinyls and plastics in furniture, appliances, paint and carpet, and in the glues that hold many of our homes together. The combustion of natural products, such as wood or brush, during structural or vegetation fires, has been shown to release high quantities of toxins. Recently, it has been discovered that the diagnosis “smoke inhalation” is really a complex of poisonings that include carbon monoxide and cyanide. Even small brush fires release lethal amounts of these substances.
One of the physiological factors affecting firefighters is heat stress, a term that, although accurate, understates the true nature of the environment in a structural fire. The superheated air in a structural fire is enough to cause a second-degree burn on exposed skin in a manner of seconds. Imagine holding a piece of burning paper in your hand. Then imagine something twice that hot or more.
Yes, we do wear protective equipment. However, when you wear 80 pounds of equipment, throw some gear over your shoulder and run up a staircase, you are generating some heat inside the suit as well.
When the fire is out, we remain on scene, and, in a process that we call “overhaul,” we open up walls and ceilings to make sure there is no fire inside. Meanwhile, the fire environment is still “off gassing” toxins at an alarming rate. Even though firefighting has always been viewed as a dangerous profession, we are beginning to realize that much of the danger occurs after the fire is out, when our guard is down and the breathing apparatus comes off.
Cyanide and carbon monoxide affect the body by interfering with the delivery of oxygen. Although there is plenty of oxygen in your body, small amounts of cyanide and carbon monoxide render the oxygen unusable. The heart and brain are most susceptible to low oxygen states, known as “hypoxia.”
I suggest an experiment. Take any athlete, or perhaps a Harvard researcher, put him in 80 pounds of gear, have him exercise at maximum capacity, heat his body up to 104 degrees or more and don’t let him cool off.
Or put him on a hillside on a 100-degree day with a hot wind blowing, dress him in fire-resistant gear, put two hoses on his back and have him run up the hill. Then give him a whiff, just a whiff, of cyanide, carbon monoxide, phosgene and oxides of nitrogen, which shut off his body’s ability to deliver oxygen to a heart, brain and muscles that are already working at maximum capacity.
Then, when he falls face down unconscious, try to tell me that his cholesterol is too high or that he must be out of shape.