Low-level CO poisoning

Low-level carbon monoxide poisoning is an issue that potentially affects a huge proportion of the population, and yet is still not fully understood.

Low-level carbon monoxide poisoning can happen anywhere.

As we move towards more environmentally friendly living, the focus is on making homes and properties "air tight" to save energy. This however can lead to poorer indoor air quality.

Awareness is also growing around the issue of ambient air pollution, and the potential consequences for health.

The growing team of carbon monoxide experts at Sheffield Hallam University has been working on several projects looking at low-level carbon monoxide exposure.

The team, which is led by Dr Mari Herigstad, were this year (2023) awarded a further grant to continue their work.

The team at Sheffield will be carrying out further work to understand the "Impact of low-level CO poisoning on the human brain".

Read more about the latest project here.

Studies show that the brain is especially vulnerable to carbon monoxide, which can lead to cognitive and neuropsychiatric problems, and potentially contribute to diseases including stroke and dementia.

The vulnerability to carbon monoxide is not set but rather changes with age. The embryo is particularly at risk with low-level carbon monoxide linked to birth defects.

Yet current studies have focused on the impact of exposure to acute, high levels, and the mechanism by which low-level carbon monoxide causes health issues in adults and embryos over time is not known.

The aim of the latest study is to address this outstanding question, and determine the effects of carbon monoxide at exposures ranging from 0-9 ppm on the brain, looking at the whole scale from cells and tissues, to organ/organism function and structure.

The findings from this study will provide a better understanding of how low-level carbon monoxide causes or contributes to disease. This knowledge is critical as it will reveal the risks and health outcomes associated with low-level carbon monoxide exposure.

Additionally, the data generated will help raise awareness, inform support and prevention strategies and identify potential routes for treatment.

Below Lucie Wilson a first-year PhD student at Sheffield Hallam University, discusses her work on the effect of low-level CO on the brain.

The CO Research Trust has previously funded research carried out by Imperial College, which looked at low-level exposure to carbon monoxide.

The project looked to improve the understanding of what constitutes low-level exposure, how can diagnosis be improved and how it can be better treated.

It is based on the assumptions that low-level carbon monoxide exposure may be much more widespread than estimated for the following reasons;

  • It is not known whether there is any safe low-level limit for carbon monoxide exposure
  • It is unknown whether repeated exposure to carbon monoxide is additive or cumulative
  • There are no reliable diagnostic tests or ‘biomarkers’ for low-level sub-acute carbon monoxide exposure
  • The clinical symptoms of non-lethal carbon monoxide toxicity are non-specific and easily confused with other medical conditions

Read more about this project here.