FIREMEDICALLY SPEAKING

Hydrogen Cyanide in Structure Fires35 Times More Toxic Than CO, This Gas Needs RespectMichael E. Murphy, RN, EMT-PChairman, NYSAFC EMS Committee

18 www.nysfirechiefs.com

WE ARE ALL AWARE the leading cause of death on the firegroundis heart attack and stroke; both diseases are attributable to heartdisease, poor diet, lack of exercise and unhealthy lifestyle. The fireservice has been addressing these issues through annual physi-cals, exercise, and nutrition programs. Despite all these preven-tive measures, the leading cause of death is still cardiovascular innature. But is it reall ?

Firefighter Joe Smith, a healthy lO-year veteran of his depart-ment, is conducting overhaul in a structure. His mask is danglingoff to the side; he is pulling down ceiling material, and he's tellingjokes with his crew. Substances are smoldering around him asone of his members uses the thermal imaging camera to look for"hot spots. n After about 15 minutes, operations switches out thecrews. Smith, while walking toward his apparatus, collapses tothe ground. Despite heroic efforts by fellow firefighters and para-medics, Smith is pronounced dead a short time after arrival at thelocal emergency department.

Hydrogen cyanide (HeN) is a colorless, odorless gas. In thechemical world, it is a simple molecule, one atom of carbon, oneatom of nitrogen and one atom of hydrogen. It is a relative dwarfin the world of organic chemistry. But this little guy packs oneheck of a punch!

It is a highly toxic substance that interferes with energy pro-duction in our cells. It is capable of shutting down the energy pro-duction in the cell in a matter of seconds. HCN is 35 times moretoxic than CO during acute exposure. Cells exposed to HCN ceaseto function and die quickly.

We have all seen the dramatized, but fairly accurate depictionsin movies of spies biting on a cyanide capsule and dying quickly.Nazi Germany used cyanide crystals, known as "ZYKLON B," inthe gas chambers of concentration camps. Tuskegee Airmen, theblack fighter pilots of World War II, were issued cyanide capsulesas part of their escape kits. It was feared, due to their race, ifcaptured they would be tortured unmercifully and the cyanidecapsule offered a quick end to the torture.

Over the last two decades there has been a Significant shiftaway from wood and natural materials toward lighter construc-tion materials composed of synthetics, plastics, and petroleum-based products. These new materials are high sources of cyanide

~ when they burn. In fact, the greatest amount of hydrogen cyanide~ produced in a fire occurs not during the fire itself, but duringIpyrolysis. Pyrolysis occurs at the beginning of a structure fire.a before flashover, when oxygen levels are low. These conditions••'1! are favorable for massive formation of HCN. We should now con-5!t~ sider HCN to be present in all structure fires and further consider~ every structure fire as a haz-mat type of incident!

The Swedish National Testing and Research Institute con-ducted tests assessing the emission ofHCN and carbon monoxide(CO)under smoldering and flaming conditions during the burn-ing of wool, nylon, synthetic rubber, plastic, and polyurethanefoam; all materials present in current building construction.They concluded that everyone of these substances emitted highquantities of HCN when burned, especially during smolderingconditions (pyrolysis). HCN is 35 times more toxic than CO dur-ing acute exposure.

On February 20, 2003, about 400 people were in The Stationnightclub in Warwick, R.I. A fire started when pyrotechnicsignited polyurethane foam lining the walls of the stage area. Theblaze quickly spread to the ceiling and wood paneling.

The emergency response was rapid and well executed. 911calls were made about 35 seconds after ignition. The firstengine arrived on the scene in less than five minutes after theinitial 911 call, and began extinguishing the blaze one minutethereafter. Despite this rapid and coordinated response, 100people died.

As part of the after investigation, the National Institute ofStandards and Technology (NIST) conducted simulations of thisfire. They measured temperature, CO, oxygen, and HCN 1.4meters above the floor and 1.6 meters from the stage. Within 90seconds, concentrations of CO and HCN soared as oxygen levelsplummeted. This created conditions that were incompatible withsustaining life.

In a Paris study conducted in 1988and 1989, blood was collected frompatients treated by the first arriv-ing EMS units to residential fires. Atotal of 109 fire victims were stud-ied-66 who survived and 43 whodied. The study showed many vic-tims who died had blood levels ofHCNin the lethal range while bloodlevels of CO were in the non-lethalrange. These results were contraryto the thinking of the day, where emphasis had been placed onCO as the culprit in smoke inhalation mortality. Instead, theresults of the study indicated HCN concentrations were directlyrelated to the probability of death, and that HCN poisoning maybe the leading cause of death in many smoke inhalation victims.

In early 2006, firefighters in Providence, R.I. were tested forHCN after three separate structure fires. Eight of 27 firefightershad elevated levels of HCN that required treatment. One fire-fighter actually collapsed on scene and had to be immediatelytreated for HCNpoisoning.

How does HCN work? HCN inhibits the production of adenos-ine triphosphate (ATP) in the mitochondria of the cell. Themitochondria are the powerhouse or engine of the cell. ATP pro-vides the energy. It is almost as if ATP is gasoline and the mito-chondria are the engines. Cut off the supply of gasoline, and theengine dies. Shut off the production of ATP in the mitochondria,and the cell dies. When the cells die, the body dies.

The signs and symptoms of HCN poisoning can be similar tothose of CO,but there are some interesting differences. Similar toCO, the patient may experience headache, flushing of skin, anxi-ety, and rapid breathing. Interestingly, bizarre behavior can bedemonstrated due to the disruption of the victim's cognitive func-tions. There have been anecdotal reports of firefighters exhibitingbizarre behavior before disappearing in the structure fire and per-ishing. Now understood to be more closely related to HCN, respira-tory arrest and myocardial infarction (heart attack) along withcardiac arrhythmias are common and result in coma and death.

The immediate treatment of HCN poisoning is administrationof intravenous hydroxocobalamin. It is related to vitamin 8-12 andbinds to the cyanide and neutralizes it, thereby rendering it nolonger toxic.

Hydroxocobalamin is commercially available in a productcalled a Cyanokit®. The Cyanokit contains two 2.5-gram vials ofhydroxocobalamin, each designed to be diluted with 100 millilitersof normal saline. Two vials (equal to five grams) of hydroxocoba-lamin are administered intravenously over 15 minutes, with thepossibility of repeating it once, depending on response.

Here's the catch, the kit retails for anywhere from $700 to $800.That's right; you read it correctly, close to $800 per dose!

Earlier, I stated that HCN is released in high quantities duringpyrolizing, which tends to be in the early stages of a structure fire,when gases are emitted under high temperature and low oxygen.We also have to remember that during smoldering conditions,

[Hydrogen cyanide] is a highly toxic substance that interfereswith energy production in our cells. It is capable of shuttingdown the energy production in the cell in a matter of seconds.HCN is 35 times more toxic than CO during acute exposure.Cells exposed to HCN cease to function and die quickly.

common at the end of a structure fire during overhaul, is a timewhen HCN and CO are still being produced. What happens dur-ing overhaul? Firefighters have a tendency to remove their SCBAmasks because "there is no more smoke." This practice, and theacceptance of this practice, needs to be put to a stop. These gasesare still present in the structure, and the members must considerthe area a haz-mat condition and remain protected.

In conclusion, HCN is present in all structure fires, but wehave only recently been considering it. All victims removed from astructure fire now must be considered to have HCNpoisoning untilproven otherwise. Especially important is that any member of theservice who had been inside the structure fire doing suppressionor overhaul and who collapses on the fireground must be consid-ered a victim of HCNpoisoning and treated as such.

REfERENCES:

1. Fortin, Jean-Luc., Turrimann, M., Domanski, L. and continued on page 20

up ISSUE 1 • 2010 19

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Accident & Health, Group Life, & AD&DRonald Oettel - Regional Director

866.626.5757 - roettei@providentbenefits.cominsurance products are underwritten by the subsidiaries of Unum Group

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20 www.nysfirechiefs.com

Kowalski. J.J. "Hydroxocobalamin for Smoke

Inhalation-Associated Cyanide Poisoning: 8

Years of Experience in the Paris Fire Brigade"

Paper presented at the annual meeting of

the National Association of EMS Physicians,Registry Resort, Naples, FI. 2009-05-25.

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Polyurethane Foam Covered Walls._Volume 2;

Interflam 2004. (lnterJ1am '04). International

Interflam Conference, 10th Proceedings.

Volume 2. July 5-7, 2004. Organized by

Interscience Communications Ltd. in asso-

ciation with National Institute of Standards

and Technology, Building Research

Establishment; National Fire Protection

Association; Society of Fire Protection

Engineers; and Swedish National Testing

and Research Institute, Edinburgh, Scotland,

Interscience Communications Ltd., London,England, 1127-1138 pp, 2004. Madrzykowski,

D.; Bryner, N. P.; Grosshandler, W. L.;

Stroup, D.W.

3. Grosshandler, W.L., Bryner, N., and

Madrzykowski, D., Report oj the Technical

Investigation oj the Station Nightclub Fire,NIST NCSTAR 2, National Institute of

Standards and Technology, Gaithersburg,

MD,June 2005. •

ABOUT THE AUTHOR:Michael E. Murphy, RN. EMT-P is chief ofoperations of Rockland Paramedic Servicesand Rockland Mobile Care in Nanuet, N.Y.He is a graduate of the University of theState of New York with a bachelor's degreein chemistry and the Long Island CollegeHospital School of Nursing where he prac-ticed emergency nursing and was a NYC 911paramedic for 15 years. Murphy is chair-man of the NYSAFC EMS Committee andrepresents the association on the NYS EMSCouncil. He can be reached at mmurphy@rocklandparamedics.org.