Carbon Monoxide Surge: 60% Rise in Poisonings Threatens Portuguese Homes

The first cold snap has barely settled and emergency doctors are already treating more people poisoned by heating fumes than in all of last year. What looks like a statistical footnote hides a dangerous trend: homes across the country are filling with an invisible gas that can turn a cosy evening into a medical emergency in minutes.

Snapshot of the numbers

According to INEM, the CIAV recorded 28 cases of carbon monoxide poisoning in Portugal by 24 November 2025, involving 22 adults and 6 children. That tally has already eclipsed the 2024 baseline, when 18 incidents were logged over 12 months. Toxicologists calculate the jump at roughly 60 %, a surge they link to earlier-than-usual cold weather and a heavier reliance on household heaters. Although none of this year’s incidents were fatal, CIAV reminds that concentrations as low as 0.04 % in the air can kill within an hour.

Why the risk grows with the cold

The same devices that keep a living room warm can, under the wrong conditions, turn lethal. When the flame in winter appliances such as braseiras, water heaters or gas stoves faces incomplete combustion and poor ventilation, it belches CO instead of harmless CO₂. Fire-fighters note that rural homes often have sealed shutters to retain heat, a habit that traps the gas indoors. Urban flats are not immune: a clogged flue in a renovated apartment can channel fumes back into the kitchen. With economic strain pushing families toward cheaper, older heaters, specialists warn that energy poverty is fast becoming a public-health matter.

Silent symptoms often misread

Victims rarely sense danger because CO is tasteless, odourless and colourless. The body’s first clues—headaches, nausea, dizziness, vague malaise or sudden drowsiness—are easy to blame on a virus. Paramedics report several cases in which patients merely opened a window, felt better, then closed it again, allowing the gas to rebuild. Invisible gas poisoning can escalate to loss of consciousness within minutes. Emergency responders urge anyone noticing symptoms among several household members at once to dial 112 or the CIAV helpline 800 250 250 without delay; early oxygen therapy dramatically improves recovery odds.

Turning vigilance into habit

Safety experts insist that routine maintenance by certified technicians is the single best defence. A well-tuned burner consumes less fuel and emits negligible CO. Proper ventilation—from cracked windows to unobstructed vents—dilutes any stray fumes. Installing carbon monoxide alarms can buy life-saving minutes; modern models beep before symptoms emerge. Keeping chimneys clear, booking a professional inspection, sticking to an annual yearly check-up and rehearsing an emergency plan with family members form the backbone of a reliable prevention strategy.

Past trends and future outlook

Portugal has wrestled with CO incidents for decades, with historical peaks in hospital admissions and a tragic high of 12 deaths in 2013. Despite aggressive prevention campaigns, hospital data show the curve bending upwards again. Authorities are betting on public awareness drives and emerging tech—such as real-time alerts and smartphone apps connected to detectors—to avoid another spike during winter 2026. Local community fire brigades are also stepping up home-visit programmes, offering free assessments in older neighbourhoods. Health officials stress, however, that technology cannot replace common sense: whenever heat is produced by flame, fresh air must find its way in.