Hit by daily episodes of dizziness, fatigue and nausea, Tracey Condron initially thought she had caught some sort of virus.<\/p>\n
\u2018I\u2019d gone from feeling full of energy to a complete wreck,\u2019 says Tracey, 44, a mother of three aged 21 to 29.<\/p>\n
And soon after these symptoms began, she noticed other changes to her health.<\/p>\n
\u2018I also started getting brain fog a lot of the time, both at home and at work,\u2019 says Tracey, who at the time was a Special Educational Needs Assistant in a primary school.<\/p>\n
\u2018Then I began noticing random overpowering smells\u00a0\u2013 sweet, floral scents that no one else could smell.\u2019<\/p>\n
Her baffled colleagues kept telling her there was no smell. \u2018They thought I\u2019d lost the plot,\u2019 says Tracey, from Rainham, Essex.<\/p>\n
In fact, Tracey\u2019s symptoms were due to her being slowly poisoned by carbon monoxide gas leaking from a faulty boiler in her bedroom\u00a0\u2013 and were it not for the quick actions of her neighbours, she could easily have died as a result.<\/p>\n
Because alone at home one January evening last year, four months after her symptoms began, things suddenly took a dramatic turn for the worse.<\/p>\n
Tracey Condron was hit by daily episodes of dizziness, fatigue and nausea but thought it was from\u00a0some sort of virus<\/p>\n<\/div>\n
![\"Tracey\u00bfs](\"https:\/\/i.dailymail.co.uk\/1s\/2026\/02\/27\/15\/106732317-15599255-image-m-23_1772206747300.jpg\")
<\/div>\n<\/p><\/div>\nTracey\u2019s symptoms were due to her being slowly poisoned by carbon monoxide gas leaking from a faulty boiler in her bedroom<\/p>\n<\/div>\n
Tracey remembers nothing beyond sitting on the sofa that evening\u00a0\u2013 she can\u2019t even recall getting into bed.<\/p>\n
It\u2019s only because her neighbours showed her footage from their video doorbell that she knows she staggered up their drive at around six the next morning.<\/p>\n
\u2018I was so weak I looked like I was going to collapse,\u2019 says Tracey. \u2018I could barely knock. Luckily, they heard me and opened the door to find me looking like death.\u2019 Her neighbours took her inside and called 999.<\/p>\n
\u2018I started vomiting in their living room and was struggling to breathe,\u2019 says Tracey. \u2018Then apparently I went stiff as a board and started convulsing.\u2019<\/p>\n
By the time the ambulance arrived, Tracey was foaming at the mouth. She suffered two cardiac arrests (meaning her heart suddenly stopped beating) and had to be resuscitated twice.<\/p>\n
In hospital, doctors were initially at a loss as to the cause of her sudden collapse. She was put into an induced coma to try to prevent the seizures she was having – fearing she might not make it, her family was called into the intensive care unit.<\/p>\n
It was during discussions with her children, who mentioned that Tracey slept next to the boiler, that doctors at Queen\u2019s Hospital, Romford, began to suspect carbon monoxide poisoning – and tests proved their hunch right.<\/p>\n
Each year, over 100 people in the UK die as a result of carbon monoxide poisoning – while many others, like Tracey, survive and can be left with life-changing health problems.<\/p>\n
The reason the gas, which is invisible and odourless, is so deadly is that it binds far more tightly to haemoglobin (a protein in red blood cells) than oxygen does, meaning it takes its place and so \u2018reduces oxygen delivery to the brain and other organs,\u2019 explains Dr Faye Begeti, a neurology specialist at Oxford University Hospitals.<\/p>\n
\u2018The brain is especially vulnerable as it normally receives around a quarter of the heart\u2019s blood flow to meet its high oxygen needs\u00a0\u2013 without adequate oxygen the tell-tale symptoms of poisoning, such as fatigue, brain fog and nausea begin.\u2019<\/p>\n
(The phantom smells Tracey noticed might have been a sign of mini-seizures in the area of the brain that processes smells, but is not characteristic of carbon monoxide poisoning.)<\/p>\n
\u2018Chronic low-level exposure can be particularly harmful, as symptoms such as headaches, fatigue, dizziness and cognitive fog can easily be mistaken for stress, viral illness or infection,\u2019 adds Dr Begeti.<\/p>\n
![\"Neurology](\"https:\/\/i.dailymail.co.uk\/1s\/2026\/02\/27\/16\/106732321-15599255-Neurology_specialist_Dr_Faye_Begeti_explains_that_the_gas_is_dan-a-1_1772209269928.jpg\")
<\/div>\n<\/p><\/div>\nNeurology specialist\u00a0Dr Faye Begeti explains that the gas is dangerous because carbon monoxide\u00a0\u2018reduces oxygen delivery to the brain and other organs\u2019<\/p>\n<\/div>\n
As levels of the gas build up in the home, it can cause severe acute carbon monoxide poisoning and seizures due to profound hypoxia (lack of oxygen reaching the brain).<\/p>\n
There can be long-term consequences, too.<\/p>\n
Dr Begeti warns of delayed encephalopathy\u00a0\u2013 a form of brain injury that can emerge days or weeks later\u00a0\u2013 caused by ongoing inflammation in brain tissue and damage to the brain\u2019s white matter (the wiring that allows different parts of the brain to communicate).<\/p>\n
\u2018People may experience cognitive decline, personality change, gait problems, seizures or psychiatric symptoms long after the exposure has ended,\u2019 she says.<\/p>\n
Carbon monoxide (CO) is produced when there is insufficient oxygen when the fuel, typically gas, is burned by flame, or when fumes that should be safely vented outside leak back into the home due to faulty, blocked or poorly maintained heating systems.<\/p>\n
According to the charity CO-Gas Safety, faulty heating and cooking appliances are most often implicated in leaks – but generators, boats and petrol-powered strimmers can all emit the gas.<\/p>\n
But because the symptoms of poisoning often mimic viral illnesses \u2018GPs may not suspect carbon monoxide\u2019, says Stephanie Trotter, president and director of CO-Gas Safety.<\/p>\n
\u2018Also blood tests\u00a0\u2013 which measure carbon monoxide in the bloodstream\u00a0\u2013 and, less commonly, breath tests, often give false negatives because the gas leaves the body very quickly.<\/p>\n
\u2018Sadly, just because CO leaves the body quickly, it does not mean the person exposed will completely recover. Many go on to suffer lasting damage to the brain and nervous system,\u2019 she adds.<\/p>\n
\u2018If someone was exposed to a high level, or exposed for a long time, it can trigger ongoing damage in the body. This means a person might seem fine at first, then feel much worse hours, days, or even weeks later.\u2019<\/p>\n
As Dr Begeti explains, carbon monoxide has a half-life in the body of about four or five hours, \u2018meaning roughly 75 per cent would be cleared in eight to ten hours\u2019.<\/p>\n
She adds: \u2018In situations where someone is being exposed repeatedly, the gas may not be fully cleared before the next exposure begins, hence chronically building up.\u2019<\/p>\n
December is the deadliest month for carbon monoxide deaths because people tend to spend more time indoors and there\u2019s an increased use of heating along with less ventilation due to windows being closed.<\/p>\n
But there is a year-round risk with barbecues or camping stoves used in tents, caravans or enclosed spaces, posing a serious risk in the summer too, according to CO-Gas Safety.<\/p>\n
![\"Tracey](\"https:\/\/i.dailymail.co.uk\/1s\/2026\/02\/27\/16\/106732325-15599255-Carbon_monoxide_is_produced_when_there_is_insufficient_oxygen_wh-a-2_1772209269929.jpg\")
<\/div>\n<\/p><\/div>\nTracey now warns people on social media about the dangers of faulty boilers and the importance of having carbon monoxide alarms\u00a0<\/p>\n<\/div>\n
Research by University College London and Liverpool John Moores University in 2012 suggested that more than three million people in the UK are regularly exposed to carbon monoxide levels of 50 parts per million or higher which, while below the levels that cause immediate collapse, can still be dangerous over time.<\/p>\n
\u2018Less than 2 per cent of carbon monoxide in the air can kill or maim in between one and three minutes\u00a0\u2013 some survivors tell me their injuries are so bad they wish they\u2019d died,\u2019 says Stephanie Trotter.<\/p>\n
After her symptoms began, Tracey had gone to her GP who gave her repeated blood tests to check whether she might be anaemic, for example, but each came back clear.<\/p>\n
All the time the levels of carbon monoxide gas in her home were building.<\/p>\n
By the time she got to hospital the lack of oxygen to her brain was so acute she was having one seizure after another and had a fractured spine and hip as a result.<\/p>\n
She spent five days in a coma, during which she continued to have seizures\u00a0\u2013 meaning doctors had to delay fitting a back brace to limit the movement of her spine and help it heal. Tracey was discharged two weeks later, a changed woman.<\/p>\n
\u2018I could barely walk,\u2019 she recalls. \u2018I had to stay with my older daughter, who lives nearby, for a few weeks because I couldn\u2019t manage on my own. Everything became difficult, lifting, dressing, shopping, even playing with my grandchildren [then aged four, two and seven months].\u2019<\/p>\n
Despite now taking takes anti-epileptic drugs, over a year on Tracey still suffers from regular seizures, some requiring urgent hospital treatment.<\/p>\n
\u2018The last serious set of seizures was in September last year,\u2019 she says.<\/p>\n
\u2018I don\u2019t recall it, but my daughter was on the phone and said I wasn\u2019t making sense. I had multiple seizures and woke up a day later not knowing what had happened.\u2019<\/p>\n
The fractures in her spine and hip healed, but have left her with daily pain. And despite taking painkillers, her mobility is now so poor she has had to give up work and depends on others for everyday tasks such as making meals, cleaning the house and food shopping.<\/p>\n
The damage to her heart\u00a0\u2013 caused by the lack of oxygen\u00a0\u2013 has now healed, but Tracey has panic attacks and has been diagnosed with post-traumatic stress disorder as a result of her ordeal. She is undergoing talking therapy.<\/p>\n
\u2018Life is not easy and I hate not being able to play with my four grandchildren [now five, three, 17 months and five months] – but I\u2019m so grateful to still be here and to have survived it,\u2019 says Tracey.<\/p>\n
Her gas supplier later confirmed her boiler was faulty; and a carbon monoxide detector installed by her landlord was also found to be not working.<\/p>\n
\u2018It was wired in and showed a green light, so it looked like it was working,\u2019 she says.<\/p>\n
\u2018There were never any safety checks in the five years I\u2019ve been here – if there had, I wouldn\u2019t have suffered prolonged poisoning that nearly killed me.\u2019<\/p>\n
Tracey is so scared it will happen again that she now has carbon monoxide detectors in every room and warns people on social media about the dangers of faulty boilers and the importance of having alarms.<\/p>\n
\u2018I sleep with the windows and doors open when my grandson stays over,\u2019 she says.<\/p>\n
\u2018He had actually stayed in my room on many weekends before I was hospitalised but thankfully, I\u2019d always kept my bedroom door open when he was there. I dread to think what could have happened to him if I hadn\u2019t.\u2019<\/p>\n
Tracey has an important message for others: \u2018If I could tell people one thing, it\u2019s to make sure you have a working carbon monoxide alarm that meets the official EN 50291 safety standard. It could save your life.\u2019<\/p>\n<\/div>\n