The poison gathers in silence, without smell or warning.
Each winter, as families seal their homes against the cold and lean on combustion-based heating, an invisible gas accumulates in the silence between habit and oversight. Carbon monoxide—odorless, colorless, born from incomplete burning—binds to the blood's oxygen carriers with a quiet efficiency that can starve the brain and heart before anyone suspects a threat. Its earliest warnings wear the disguise of ordinary winter illness, allowing the danger to deepen unnoticed. Toxicologist Fernando Torres observes that this annual cycle of preventable harm persists not from ignorance of the solution, but from the distance between knowing and acting.
- A gas that cannot be seen, smelled, or tasted accumulates in sealed winter homes while families believe they are simply resting through a cold or flu.
- Carbon monoxide hijacks hemoglobin with greater force than oxygen itself, silently depriving the brain and heart of what they need to survive—often before anyone realizes the room is the danger.
- The symptoms—headache, dizziness, nausea, drowsiness—so closely mimic seasonal illness that victims wait for the virus to pass while the poisoning quietly worsens.
- When poisoning is suspected, every second shapes the outcome: ventilate immediately, move the person to fresh air, loosen their clothing, call for emergency care, and shut off the combustion source.
- Toxicologist Fernando Torres insists the tragedy is structural, not inevitable—regular equipment maintenance, basic ventilation habits, and refusing to use ovens as heaters would eliminate most cases before they begin.
Cuando llega el invierno, las ventanas se cierran. Las familias sellan sus hogares contra el frío y encienden la calefacción. Lo que no pueden ver, oler ni saborear ya circula por el aire: el monóxido de carbono, un gas que nace de la combustión incompleta de estufas, calefones y braseros. Fernando Torres, toxicólogo y director de la Escuela de Química y Farmacia de la Universidad Andrés Bello, ha visto repetirse este ciclo suficientes veces como para saber que es casi completamente prevenible.
El peligro surge de una combinación de hábitos cotidianos. En invierno, las personas permanecen más tiempo en espacios cerrados y dependen más de la combustión —gas, parafina, leña, carbón— para calentarse. Cuando esa combustión es incompleta, el artefacto produce monóxido de carbono en lugar de dióxido de carbono. En un cuarto sellado, el gas se acumula rápidamente y sin aviso. Lo que lo hace tan letal es la forma en que engaña al cuerpo: al inhalarse, se une a la hemoglobina con una afinidad mucho mayor que el oxígeno, privando a los órganos vitales del oxígeno que necesitan para funcionar. El daño neurológico, el fallo cardíaco y la pérdida de conciencia pueden sobrevenir sin que la víctima note nada anormal a su alrededor.
Las señales tempranas son engañosas. Dolor de cabeza, mareos, náuseas, debilidad, somnolencia y dificultad para concentrarse imitan tan fielmente un resfrío o una gripe que las personas suelen atribuirlos a un virus de temporada. Descansan, esperan, y el gas sigue acumulándose. Para cuando se establece la conexión —si es que se establece— el daño puede ser grave o irreversible.
Torres es enfático respecto a cómo actuar ante una sospecha de intoxicación: ventilar el espacio de inmediato, protegerse antes de ingresar a una habitación contaminada, trasladar a la persona afectada al aire fresco, aflojar su ropa para facilitar la respiración y llamar a emergencias sin demora. La fuente de combustión debe apagarse, siempre que hacerlo no genere un riesgo adicional.
Pero Torres vuelve siempre al mismo punto: la mayoría de estos casos no necesita ocurrir. El mantenimiento regular de estufas y calefones detecta fallas antes de que se vuelvan letales. Mantener los espacios ventilados, incluso en invierno, permite que los gases peligrosos se disipen. No usar el horno ni la cocina como fuente de calefacción elimina una categoría entera de riesgo. Las herramientas existen. El conocimiento existe. Lo que resta es la decisión de utilizarlos.
Winter arrives and the windows close. Families seal their homes against the cold, turning up the heat. What they cannot see, smell, or taste is already moving through the air—carbon monoxide, a gas born from the incomplete burning of stoves, water heaters, and braziers. Each year the pattern repeats: as heating systems run longer and ventilation drops, poisonings spike. Fernando Torres, a toxicologist and director of the School of Chemistry and Pharmacy at Andrés Bello University, has watched this cycle unfold enough times to know it is almost entirely preventable.
The danger lies in a simple collision of habits. Winter forces people indoors for longer stretches. They rely more heavily on combustion-based heating—gas, kerosene, wood, charcoal—to stay warm. When that combustion is incomplete, whether from lack of oxygen or equipment failure, the furnace produces carbon monoxide instead of carbon dioxide. In a sealed room, the gas accumulates quickly. No alarm sounds. No smell warns you. The poison gathers in silence.
What makes carbon monoxide so lethal is the way it tricks the body. When inhaled, the gas binds to hemoglobin—the protein that carries oxygen through the blood—with an affinity far stronger than oxygen itself. The result is that vital organs are starved of the oxygen they need to function. Neurological damage can follow. The heart can fail. Consciousness can slip away. All of this happens without the victim noticing anything wrong in the room around them. The most common sources of poisoning in winter are faulty stoves, defective water heaters, broken braziers, gas leaks, and smoke from incomplete combustion.
The early warning signs are deceptive. A person poisoned by carbon monoxide experiences headache, dizziness, nausea, vomiting, weakness, drowsiness, trouble concentrating, and shortness of breath. These symptoms mirror a common cold or the flu so closely that people often misattribute them. Someone feels sick and assumes they have caught a winter virus. They rest. They wait. The gas continues to accumulate. The poisoning deepens. By the time the connection is made—if it is made at all—the damage may be severe or irreversible.
Torres is emphatic about what to do if poisoning is suspected. Speed matters absolutely. The first action is to ventilate the space immediately. Whoever responds must protect themselves before entering a contaminated room. The poisoned person should be moved to fresh air at once, their clothing loosened to aid breathing, their emotions steadied. If their skin is cold, they need warmth. Emergency medical care cannot wait. The source of combustion should be shut off, provided doing so creates no additional danger.
But Torres returns always to the same point: most of these cases never need to happen. Maintenance prevents them. Regular inspection and servicing of stoves and water heaters catches problems before they become lethal. Keeping rooms ventilated, even in winter, allows dangerous gases to escape. Refusing to use ovens or stovetops as heating sources eliminates an entire category of risk. The tools exist. The knowledge exists. What remains is the choice to use them.
Citações Notáveis
During winter, people spend more time in closed spaces and use heating systems that burn organic matter more frequently. When that combustion is incomplete, carbon monoxide accumulates rapidly if the environment is not ventilated.— Fernando Torres, toxicologist and director of the School of Chemistry and Pharmacy at Andrés Bello University
The similarity with other common winter illnesses can cause a person not to associate what they feel with poisoning, which delays reaction and worsens the condition.— Fernando Torres
A Conversa do Hearth Outra perspectiva sobre a história
Why does carbon monoxide poisoning spike specifically in winter? Couldn't it happen any time of year?
It could, but winter creates the perfect conditions. People close their windows and doors to keep heat in, and they run combustion-based heating systems much longer. In summer, you open a window without thinking. In winter, you seal the house tight.
The symptoms sound like flu. How many people do you think mistake poisoning for illness and never get help?
That's the real danger. Someone gets a headache and feels tired, so they rest at home near the heater. The gas keeps accumulating. By the time they realize something is wrong, they may have lost consciousness or suffered permanent damage.
You mentioned that carbon monoxide binds to hemoglobin more strongly than oxygen. Why does that matter so much?
Because your organs don't know the difference. The hemoglobin carries the carbon monoxide instead of oxygen, and the brain, heart, and other vital tissues simply starve. There's no pain, no signal that something is wrong—just gradual failure.
If someone suspects poisoning right now, what's the single most important thing they should do?
Get out of the space and into fresh air immediately. Don't wait to call a doctor from inside the house. Don't try to fix the heater yourself. Ventilate first, then seek emergency care.
Torres says most cases are preventable. What does that actually require?
Regular maintenance of heating equipment, keeping some ventilation even in winter, and never using an oven or stove as a heat source. It's not complicated. It's just discipline.