The Silent Killer – A Case Series on Carbon Monoxide Poisoning Following a Domestic Fire

Synnah, Mebanrilin; Meena, Mahesh Chand; Sinhmar, Deepti

doi:10.22038/apjmt.2026.89628.1527

The Silent Killer – A Case Series on Carbon Monoxide Poisoning Following a Domestic Fire

Document Type : Case Series

Authors

Mebanrilin Synnah ¹

Mahesh Chand Meena ²

Deepti Sinhmar ³

¹ Senior Resident, Department of Forensic Medicine & Toxicology, Shillong Medical College, Pasteur Hills, Shillong, Meghalaya, India

² Associate Professor, Department of Forensic Medicine & Toxicology, UCMS & GTBH, Delhi, India

³ Senior Resident, Department of Forensic Medicine & Toxicology, UCMS & GTBH, Delhi, India

10.22038/apjmt.2026.89628.1527

Abstract

Introduction: Carbon monoxide (CO), the “silent killer,” is a colourless, odourless gas that binds haemoglobin with approximately 200–240 times greater affinity than oxygen, forming carboxyhaemoglobin (COHb), causing tissue hypoxia and death. Fire-related CO poisoning remains a major but under-recognised cause of mortality in poorly ventilated domestic environments.
Case report: We present a retrospective forensic case series of six fatalities from three families who died in a single domestic fire in a rented building in Shastri Park, Delhi, after a mosquito coil fell onto a mattress and ignited it. Medico-legal autopsies included external and internal examination, while blood and viscera were submitted for toxicological analysis. Carbon monoxide was detected qualitatively, and blood ethyl alcohol was quantified.
Discussion: Five of six victims tested positive for CO; quantitative COHb saturation was unavailable. Three showed co-detected ethyl alcohol (38.2–94.7 mg/100 mL). Common findings included soot on the body, clothing, tongue and nostrils; cherry-red lividity, blood and muscle; respiratory tract oedema, congestion and soot deposition; and petechial haemorrhages in the lungs and heart. Victims included a 2-year-old child, a 25-year-old woman in early pregnancy, and one adult with 15–20% total body surface area burns, the only victim with significant thermal injury.
Conclusion: Fire deaths with minimal burns may primarily result from smoke inhalation and asphyxiant gas poisoning. Quantitative COHb and cyanide analysis, alongside careful autopsy, is essential for accurate death certification. Preventive measures, including safe mosquito-coil and candle placement, functioning smoke and CO detectors, and accessible evacuation routes, are critical.

Keywords

Smoke inhalation injury

Suffocation

Carbon Monoxide

Carboxyhaemoglobin

Subjects

Forensic Medicine

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