- 170 internal contributors mobilised to move from a requirement to collective ownership.
- 2A distinctive scope: laboratories, animal facilities, scientific equipment and international collaborations.
- 3From measurement to research: an LCA of hepatitis B screening published in the WHO Bulletin.
- 4Four years later, climate is one of the Institute's annual report's three pillars.
Institut Pasteur is one of the world's most prestigious research institutes. Nobel Prizes, fundamental research into infectious diseases, an international network of laboratories. Its CSR approach was already historically well established, and the Institute had needed little prompting to take an interest in its environmental impacts in the broad sense. But climate as a strategic subject in its own right - with everything that entails in rigorous quantification, a reduction pathway and changes to practices - had not yet found its place in the institution. What changed around 2020-2022 was that demand began coming from within.
1When researchers start asking questions
It began fairly organically. Groups of doctoral students and researchers started organising awareness-raising workshops among themselves - Climate Fresk sessions, informal discussions, initiatives born in corridors and laboratories rather than management committees. It was not a protest, or even a formal demand. It was something deeper: a collective awakening led by people whose training and profession place them on the front line of scientific knowledge. They were reading climate literature, grasping its severity, and wanted their own institution to act accordingly.
The CSR department watched this momentum emerge and made a choice that proved foundational: rather than letting these initiatives fragment into silos, pool the energy and structure the institutional response. Respond to demand with a method. And for scientists, the first step of a method is always measurement.
Measure first, decide afterwards
Bilan Carbone® emerged as the logical answer. It is France's reference method for quantifying an organisation's greenhouse gas emissions, and an exercise proven in hundreds of organisations. But in a research institute, it has a feature that should not be underestimated: the method is based on estimates, rather than experiments. You do not connect sensors or take direct measurements. You reconstruct flows from activity data, combine them with emission factors, and produce orders of magnitude. For researchers used to direct measurement and experimental reproducibility, this is a methodological paradigm shift that required time to explain, contextualise and gain acceptance.
2A scope unlike any other
An institute like Pasteur is not a head office with offices, a canteen and a company-car fleet. It is a living research campus, with containment laboratories, cold rooms, animal facilities, vaccination centres open to the public, classrooms for doctoral training, and international conferences bringing researchers from around the world. The data collection scope has a complexity rarely encountered elsewhere. We had to identify the right contacts in each department, adapt our collection tools to very different activities, and build a truly bespoke methodological framework.
The Pasteur assignment in figures
A long-term commitment with exceptional internal engagement
The exercise also reveals emission sources specific to research, found in no ordinary SME: purchases of laboratory reagents and consumables, energy consumption by scientific equipment running continuously, and international travel for collaborations and field research. And behind these figures is a question running through the whole exercise: what is the place of research in a world that must reduce its emissions? How can we continue doing excellent science, which sometimes requires flying or consuming large amounts of energy, while accepting our climate responsibility?
The cultural challenge: speaking the same language
The challenge of this assignment was not only computational. It was deeply cultural. When presenting a carbon footprint to internationally recognised researchers, you cannot arrive with ready-made conclusions. You have to show the method, explain assumptions, quantify uncertainties and accept that every figure will be questioned. That is exactly what we know how to do, and probably where our background made the difference: we have completed doctorates, know the conventions of academia, and understand what it means to "show your sources" and "discuss the margin of error". This familiarity with scientific culture allowed us to build a dialogue between equals, rather than a conventional consultant-client relationship. Explain rather than pronounce. Engage rather than impose.
We moved from a compliance exercise to a scientific conversation about reduction levers. That was when the footprint began producing real effects.
370 contributors: when ownership replaces obligation
Over the months, the circle of people involved grew naturally. More than 70 people contributed to the approach - researchers, technicians, administrative staff and doctoral students. This figure is significant: it shows that the subject had stopped being a dossier carried solely by the CSR department and become a project people identified with. We did not need to impose a top-down plan saying "here is what management has decided, apply it". We built a framework allowing everyone to contribute at their own level, and people took ownership because they found it meaningful.
We have encountered this dynamic in all our assignments since, and it has become a working principle: lasting transformations come from ownership rather than obligation. When people understand why we measure, what decisions it enables, and have room to contribute, they engage with an energy far beyond anything a top-down action plan can produce.
4From measurement to research: when LCA enters the laboratory
One of the most unexpected extensions of this assignment was the publication of a scientific article in the Bulletin of the World Health Organization. The idea was bold: apply Life Cycle Assessment methodology to a hepatitis B screening protocol in The Gambia, to assess the carbon footprint of different diagnostic processes and identify those that could reduce the environmental impact of care, particularly in a resource-constrained setting.
This paper, co-written with the Institute's researchers and published in a high-impact-factor journal, marked an important milestone. It showed that the carbon footprint could become a parameter of research itself - rather than a peripheral gimmick added afterwards, a criterion integrated into the scientific process alongside cost or clinical effectiveness. It is a pilot project, but it opens a path.
Infectious diseases intensified by climate change
There is a deep consistency to this whole approach, something the Institute's teams did not miss: Pasteur works on infectious diseases, and these diseases are directly intensified by climate change. Geographic expansion of vectors, shifting endemic areas, and increasing zoonoses linked to deforestation and ecosystem disruption. Reducing the Institute's carbon footprint is, in a way, an extension of its primary mission: prevent rather than cure. Act on causes rather than treating consequences.
5Making it visible: an exhibition at the heart of the campus
In 2024, to take awareness-raising further and embed the subject in the Institute's daily life, an exhibition was installed in the greenhouse on the Paris campus. Over several days, the carbon footprint results, work on LCA of care, and links between health, climate and research were presented to all staff in an open, accessible format.
It was neither top-down communication nor a reporting exercise. It was a space for conversation, designed to fit the Institute's culture: show, explain, question, let people form their own opinions. And it was a clear success, because the format was right. When speaking to scientists, you do not tell them what to think. You give them the evidence and trust them.
6Four years later: what small steps produced
Personally, this may be the lesson that makes us proudest of this assignment. You do not see radical change overnight. It is not one event, conference, footprint exercise or even exhibition that transforms an organisation of this scale. It is an accumulation of small steps, conversations, adjustments, modest victories and moments when you have to explain again because teams have changed or priorities have shifted.
But stepping back and looking at the distance covered over four years, the transformation is there. At the start, we had to build a common foundation - emotional, methodological and computational. A subject that did not yet have a place in governance. Today, climate change is one of the three pillars of Institut Pasteur's annual report. It is a consideration integrated into management committees. It is a lens informing strategic decisions. The approach has extended beyond the initial Paris scope.
Above all, we moved from a point where we had to convince people the subject existed to one where the question is no longer "should we act?" but "how can we go further?". That transition takes time, cannot be decreed, and creates the full value of long-term support.
We moved from scattered initiatives to an integrated strategy. Not in a day. Through four years of methodical work, adaptation and a little shared persistence.
7Carbon footprints in research institutes: what differs from a conventional company
After four years supporting Institut Pasteur and several assignments in other research and healthcare organisations, we can draw some conclusions about what makes a research institute's carbon footprint fundamentally different from a conventional company's.
First, the scope is more complex. A research laboratory's emission sources differ from those of an office or factory: scientific consumables, technical gases, equipment operating continuously, international collaborations generating structural air travel. Emission factor databases do not always cover these activities, requiring bespoke factors and documentation of every assumption.
Second, the audience is different. Researchers used to scientific rigour do not readily accept unjustified approximations. The support must meet the methodological standard: show sources, quantify uncertainties, explain scope choices. A consultant arriving with a generic PowerPoint will not last five minutes. It is a demanding context, but also the one where our training as physicists with doctorates makes the greatest difference.
Finally, long timescales are the norm. In an SME, a carbon footprint can produce its first effects in six months. In a research institute, transformation is slower but deeper. You have to accept that ownership takes time, resistance is sometimes intellectual before it is organisational, and results are measured in years rather than quarters.
8What this assignment taught us
The fundamental lesson is that the environmental transformation of an institution like Pasteur cannot be decreed. It is built through bespoke work, listening to people on the ground, and continually adapting the message to the audience. Here, the audience was world-class scientists. We had to meet the standard, methodologically and intellectually. And we had to accept that the pace would differ from a conventional six-month assignment ending with a deliverable and an invoice. This experience informs our support for carbon footprints and action plans, with scope and engagement arrangements tailored to each organisation.
What worked: starting with measurement rather than awareness-raising. Answering questions rather than arriving with ready-made answers. Building a framework that makes people want to contribute rather than a plan requiring compliance. And sustaining the effort over time, without letting up, convinced that every small step counts and the effects accumulate.
