# It is time to consider the climate crisis in haematology

Robin Noel, Aude Charbonnier, Bérénice Schell, Arthur Dony, Charles Toulemonde, François Eisinger, Olivier Decaux, Joanna Lotocka, Edith Julia, Alya Perthus, et al.

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## To cite this version:

Robin Noel, Aude Charbonnier, Bérénice Schell, Arthur Dony, Charles Toulemonde, et al. It is time to consider the climate crisis in haematology. Clinical Hematology International, 2025, 7 (1), pp.55-59.
10.46989/001c.133524. hal-05015061

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Distributed under a Creative Commons Attribution 4.0 International License
Correspondence

IT IS TIME TO CONSIDER THE CLIMATE CRISIS IN HAEMATOLOGY

Robin Noel¹ª, Aude Charbonnier¹, Bérénice Schell², Arthur Dony³, Charles Toulemonde⁴, François Eisinger⁵,
Olivier Decaux⁶, Joanna Lotocka, Edith Julia⁴, Alya Perthus⁷, Mathilde Seguin⁸, Aurélie Cabannes-Hamy⁹,
Pierre Sujobert¹⁰, Laurie Marrauld¹¹, Caroline Besson⁹

¹ Hematology, Institut Paoli-Calmettes, France, ² Haematological Biology, Centre Hospitalier Universitaire Henri-Mondor, France, ³ Hematology, Centre Hospitalier Métropole Savoie, France, ⁴ Hematology, Hospices Civils de Lyon, France, ⁵ Research, Institut Paoli-Calmettes, France, ⁶ Hematology, Centre Hospitalier Universitaire de Rennes, ⁷ Hematology, Centre Hospitalier Universitaire de Rennes, France, ⁸ Hematology, Assistance Publique - Hôpitaux de Paris, France, ⁹ Hematology, Centre Hospitalier de Versailles, France, ¹⁰ Hematological Biology, Hospices Civils de Lyon, France, ¹¹ University of Rennes, École des Hautes Études en Santé Publique, France

Keywords: Haematology, public health, climate change, clinical trials

https://doi.org/10.46989/001c.133524

Clinical Hematology International

Vol. 7, Issue 1, 2025

Climate crisis (CC), pollution and destruction of biodi-
versity represent a major threat to present and future so-
cieties. Global pollution is the single largest cause of envi-
ronmental deaths, with approximately 9 million premature
deaths estimated per year.¹ As stated by the World Health
Organization, 'recent research attributes 37% of heat-re-
lated deaths to human-induced climate change" and 'con-
servatively projects 250,000 additional yearly deaths by the
2030s due to climate change impacts'.² The Intergovern-
mental Panel on Climate Change (IPCC) publishes compre-
hensive reports on the potential impacts of on society's
health and well-being, possible future challenges and
risks,³ along with recommendations for mitigation and
adaptation; the Lancet Countdown monitors the evolving
health profile of climate change, providing an independent
assessment of the delivery of commitments made by gov-
ernments worldwide under the Paris Agreement.⁴,⁵

The healthcare system faces a dilemma with its own sig-
nificant impact on the environment, particularly in wealthy
countries, and the increasing climate-related morbidity and
mortality. According to The Shift Project, the French
healthcare system is responsible for over 8% of the national
carbon footprint (40 to 61 million tons of CO2 equivalent
(MtCO2e), i.e. 6.6 to 10%; **Figure 1**), with roughly 50% of
these greenhouse gas (GHG) emissions coming from the
procurement of drugs and medical devices,⁶ findings which
align with other studies and confirm the significant carbon
impact of the healthcare systems in developed countries.⁷,⁸

Many believe that in order to ensure humanity's pro-
tection, healthcare should be addressed and assessed like
other sectors of the economy in light of the ecological tran-
sition. As stated in a United Nations Charter itself, 'our
present actions shouldn't jeopardize everyone's future as
a matter of transgenerational and global responsibility'.⁹
Others might argue that medical care should always prevail
over other considerations - as some sort of 'sanctuary' - and
not be taken into account when mitigating GHG emissions

and pollution, an argument that could also apply to other
sectors such as transport, agriculture or defense. Neverthe-
less, reducing GHG emissions is a matter of complying with
carbon-neutral goals by 2050, and the early decarboniza-
tion of healthcare will therefore strengthen its resilience in
a changing world.

It is time to tackle this vast subject of evaluating and re-
ducing healthcare GHG emissions. Others and we believe
that just as with any goods and services, the environmental
footprint of medicines and medical devices must be as-
sessed and disclosed to medical providers, patients and all
citizens. Measuring GHG emissions is an emerging topic in
medicine. Little is known about the impact of treatments
in hematology, and very few studies have been published
in other medical fields (dialysis, critical care, etc.) to assess
more sustainable treatment strategies.¹⁰⁻¹⁸

While innovation is one of the pillars of hematology,
there is currently limited data on the impact of new drugs
or therapeutic strategies (CART-cells, tyrosine kinase in-
hibitors, bispecific antibodies, etc.) on GHG emissions.¹⁹
In practice, we mainly assess the benefit/risk ratio of our
treatments based on the uniqueness of each patient accord-
ing to survival rates and safety profiles. We should estimate
the environmental impact of our therapeutic strategies and
promote research to achieve the same goals regarding sur-
vival and quality of life with lower GHG emissions. For ex-
ample, the use of stop-and-start strategy versus continu-
ous treatment could be expanded beyond chronic myeloid
leukemia. Tyrosine kinase inhibitors have successfully al-
lowed exploration of stop-and start treatments without im-
pairing the survival of patients, while reducing costs and
resources.²⁰ This approach has also recently been imple-
mented in chronic lymphoid leukemia, although in other
chronic diseases such as multiple myeloma the standard
largely remains continuous treatment. It is of utmost im-
portance to question such an approach, and that sequential
<figure><img src="image_3.png" /><figcaption>**Figure 1.** Distribution of GHG emissions from the French health sector (MTCO₂e: Metric Tons of carbon dioxide equivalents CO₂ - Courtesy of the ShiftProject):</figcaption></figure>

A: Energy (heating, water heating, etc.)

B: Medical gases consumption and air conditioning

C: Electricity

D: Procurement: drug purchase

E: Procurement: medical equipment purchase

F: Food supply

G: Patients and visitors transportation

H: Manufacturing of durable goods (buildings, IT system, heavy medical devices, etc.)

I: Waste and services

J: Staff commuting

treatments should be systematically investigated in clinical trials.

Moreover, clinical trials should be transparent about their global GHG production and commit to using sustainable methods.²¹⁻²³ The Low Carbon Clinical Trials Group²² provides methods and guidance for reducing the carbon footprint of clinical trials. Emissions from clinical trial units, as well as travel by staff and patients, are identified as the primary sources of GHG emissions. In this context, remote enrollment and tele monitoring could have a significant impact. Follow-up exams are often numerous and may be reduced particularly in asymptomatic patients with favorable chronic conditions, such as follicular lymphoma for instance. Additionally, using synthetic control arms based on data from recent trials can reduce the number of patients needed for enrollment.²⁴ Moreover, they should also consider their environmental impact as an output and gradually change their model to test therapeutic modalities with lower emissions such as shorter treatment durations, with a global approach to health.

As hematologists, simple changes to our daily routine can have significant positive impacts. For example, increasing the number of online consultations,²⁵⁻²⁷ cutting down on the amount of unnecessary diagnostics and routine monitoring exams, or favoring the administration of treat-

ment orally over IV.²⁸ Moreover, promoting more sustainable and equitable medical meeting attendance via hybrid conferences, for example, can have a strong impact.²⁹ Finally, in the future, leading expert opinion groups for each neoplasm should also consider incorporating environmental impact into their decision-making when issuing routine guidelines, as data become available.

Education on this subject is fundamental and should be incorporated into all levels of the medical curriculum to ensure future physicians promote sustainable medical practices. Seeing as this topic extends beyond the medical community and touches all members of society, as physicians, we have a responsibility to raise public awareness, enabling people to take part in the discussion and transition process.

Finally, to achieve a greater purpose we must advocate for more drastic measures on a larger scale. Policy makers and drug agencies - such as the FDA and EMA - should implement impact assessments of drugs and therapeutic strategies for both present and future patients. We need long-term and global assessments of the benefit/risk ratio, otherwise, future generations might not benefit at all from our innovations. Governmental regulatory authorities could implement environmental criteria within the research field, thus fostering eco-responsible research projects and guidelines on how to mitigate the CC impact.
In conclusion, the CC is also a dire health emergency. Our medical obligations are not only to offer the best possible patient care based on current knowledge, but from a broader public health perspective, to ensure people are able to maintain a high quality of health going forward, while incorporating sustainable medical practices in our decision-making.³⁰ This would provide an opportunity to create deeper meaning and responsibility withinematology, and to motivate future generations of health care providers. If the medical community chooses to ignore the warning signals expressed by other scientific communities, we might fail our primary duty to our patients' health, jeopardize that of future generations, and breach the guidance of good medical practice.

## AUTHORS' CONTRIBUTION

Conceptualization: Robin Noel (Equal), Aude Charbonnier (Equal), Caroline Besson (Equal). Writing – original draft: Robin Noel, Aude Charbonnier (Equal), François Eisinger (Equal), Caroline Besson (Equal). Writing – review & editing: Bérénice Schell (Equal), Arthur Dony (Equal), Charles Toulemonde (Equal), Olivier Decaux (Equal), Joanna Lotocka (Equal), Edith Julia (Equal), Alya Perthus (Equal), Mathilde Seguin (Equal), Aurélie Cabannes-Hamy (Equal), Pierre Sujobert (Equal), Laurie Marrauld (Equal).

## COMPETING OF INTEREST - COPE

Authors have no competing interests to disclose for this article.

Submitted: December 12, 2024 BST. Accepted: January 28, 2025
BST. Published: March 27, 2025 BST.

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This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CCBY-4.0). View this license's legal deed at http://creativecommons.org/licenses/by/4.0 and legal code at http://creativecommons.org/licenses/by/4.0/legalcode for more information.
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