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Doing Our Part In The Fight Against Global Warming: Can We Reduce The Carbon Footprint Of Clinical Trials Through The Use Of A Footprinting Model?

5 June 2023
World Environment Day 2023 photo of plant held in a human hand

World Environment Day is a particularly poignant time to remind ourselves of the current state of play in our efforts to preserve our planet and our fight against global warming. The latest UN report (2022) on emissions states that the world, worryingly is still falling short of the 2015 Paris Climate Agreement and there remains no credible pathway to limiting global rising temperatures to 1.5°C above pre-industrial levels. Without an urgent global effort across all sectors, we are likely heading for catastrophic climate disasters, which would impact millions on a humanitarian and economic scale. To put it simply, we are not doing enough to preserve our planet for the generations to come.

Clinical trials contribute significantly to carbon emissions across the world, but we still know very little about their specific carbon footprints. Introducing a foot-printing model when considering whether to conduct a clinical trial could have a role in reducing the carbon footprint and be a significant contributor in the fight to reduce global warming.

What do we know about the contribution of clinical trials to this problem? Currently, there are 350,000 national and international trials registered with, amounting to an estimated 27.5 million tonnes of CO2 emissions using the average calculated by the Sustainable Trials group. This amount of carbon emissions equates to just under a third of the total CO2 emissions of Bangladesh annually, a country of 163 million people.

I have had a long-standing interest in environmental issues and also opportunities to change academic and clinical practice to protect our planet. As part of my intercalated degree studying population medicine, I was instantly interested in a project that focused on developing a carbon foot-printing model to reduce carbon emissions in clinical trials. Working with Professor Kerry Hood and Dr Joanne Euden, I am piloting a clinical trials footprinting model as part of a broader project run by the Institute for Cancer Research (ICR) and the University of Liverpool (UoL), funded by the National Institute for Health Research.  The guidance has been developed by ICR and UoL with the aim of being used prospectively during the design phase of a trial before funding is secured. The current project will be a pilot of this carbon footprint guidance toolkit, and a field test of the prototype that they have developed.

The scope for this project is an extremely exciting prospect, with the possibility to reduce the contribution of emissions from clinical research significantly. The prospective nature will allow trial teams to consider the sustainability of their clinical trial and evaluate areas within their trial where there may be opportunity to reduce their carbon footprint, without compromising the validity and quality of their trial. Some of these changes in design may seem insignificant and some only see a small offset in the amount of carbon emissions they produce, however, considering the 350,000 trials registered with ClinicalTrials.Gov, implementing these small changes across one trial and repeating this step across all future trials could have a substantial effect on the contribution of the research sector to global warming. This is the start of a sustained, collective effort needed by all within the research sector to protect our planet from the effects of climate change.

I have really enjoyed working on this project so far and am looking forward to continuing to footprint further clinical trials to understand more about how the choices we make impact our effect on the environment. Preliminary results from the pilot study by ICR of two clinical trials are available here:

– written by Elis Midha



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