Planetary Health Rounds
What is the definition of planetary health?
An interdisciplinary field that recognizes the interconnection between human health and the health of the Earth's natural systems, including the atmosphere, oceans, biodiversity, and ecosystems.
Myers SS. Planetary health: protecting human health on a rapidly changing planet. Lancet. 2017 Dec 23;390(10114):2860-2868. doi: 10.1016/S0140-6736(17)32846-5. Epub 2017 Nov 13. PMID: 29146123.
What is the healthcare sector's carbon footprint (percentage of greenhouse gas emissions)?
Approximately 4-5% of greenhouse gas emissions.
Braithwaite J, Smith CL, Leask E, Wijekulasuriya S, Brooke-Cowden K, Fisher G, Patel R, Pagano L, Rahimi-Ardabili H, Spanos S, Rojas C, Partington A, McQuillan E, Dammery G, Carrigan A, Ehrenfeld L, Coiera E, Westbrook J, Zurynski Y. Strategies and tactics to reduce the impact of healthcare on climate change: systematic review. BMJ. 2024 Oct 8;387:e081284. doi: 10.1136/bmj-2024-081284. PMID: 39379104; PMCID: PMC11459334.
What is personal protective equipment (PPE) and what is its purpose?
PPE serves as a critical barrier to shield healthcare workers from droplets, aerosols, contaminated body fluids, and surfaces that might transmit infectious diseases. Some examples include gowns, gloves, masks, respirators, eye protection, and/or boot coverings.
Verbeek JH, Rajamaki B, Ijaz S, Sauni R, Toomey E, Blackwood B, Tikka C, Ruotsalainen JH, Kilinc Balci FS. Personal protective equipment for preventing highly infectious diseases due to exposure to contaminated body fluids in healthcare staff. Cochrane Database of Systematic Reviews 2020, Issue 5. Art. No.: CD011621. DOI: 10.1002/14651858.CD011621.pub5.
What inhalers lead to the largest CO2 emissions?
From 2014 to 2024, inhalers in the US generated an estimated 24.9 million metric tons of CO2 equivalent emissions, with 98% coming from metered-dose inhalers (MDIs).
Feldman WB, Han J, Raymakers AJN, Furie GL, Chesebro BB. Inhaler-Related Greenhouse Gas Emissions in the US: A Serial Cross-Sectional Analysis. JAMA. 2025;334(18):1638–1649. doi:10.1001/jama.2025.16524.
What are planetary health rounds?
Educational sessions that integrate planetary health principles (interconnections between environmental changes, climate changes, and human health) into medical training. These sessions aim to improve knowledge of climate-health connections, enhanced systems thinking, development of sustainable healthcare practices, and preparation for climate-related patient care challenges.
Visser EH, Oosterveld B, Slootweg IA, Vos HMM, Adriaanse MA, Schoones JW, Brakema EA. The Development and Characteristics of Planetary Health in Medical Education: A Scoping Review. Acad Med. 2024 Oct 1;99(10):1155-1166. doi: 10.1097/ACM.0000000000005796. Epub 2024 Jul 1. PMID: 38954502.
Oudbier J, Sperna Weiland NH, Boerboom T, Ravesloot JH, Peerdeman S, Suurmond J. An evidence-based roadmap to integrate planetary health education into the medical curriculum. Med Teach. 2022 Nov 17:1-5. doi: 10.1080/0142159X.2022.2137015. Epub ahead of print. PMID: 36395753.
What contributes to the environmental footprint from Canada's health care system?
This footprint encompasses both direct emissions from healthcare facilities and vehicles, as well as indirect emissions from the production and transport of medical equipment, pharmaceuticals, and other related goods/services.
Eckelman MJ, Sherman JD, MacNeill AJ. Life cycle environmental emissions and health damages from the Canadian healthcare system: An economic-environmental-epidemiological analysis. PLoS Med. 2018 Jul 31;15(7):e1002623. doi: 10.1371/journal.pmed.1002623. PMID: 30063712; PMCID: PMC6067712.
What is a sustainable PPE alternative?
Reusable PPE offers substantial environmental and economic benefits compared to disposable options. Hospitals adopting reusable gowns have reported 50% cost reduction in gown expenditures. Reusable gowns can withstand 75-100 laundering cycles compared to single-use disposable gowns.
Baker N, Bromley-Dulfano R, Chan J, Gupta A, Herman L, Jain N, Taylor AL, Lu J, Pannu J, Patel L and Prunicki M (2020) COVID-19 Solutions Are Climate Solutions: Lessons From Reusable Gowns. Front. Public Health 8:590275. doi: 10.3389/fpubh.2020.590275.
Where does the environmental impact in metered-dose inhalers (MDIs) primarily stem from?
Hydrofluoroalkane (HFA) propellants in MDIs are potent greenhouse gases.
Woodcock A, Beeh KM, Sagara H, Aumônier S, Addo-Yobo E, Khan J, Vestbo J, Tope H. The environmental impact of inhaled therapy: making informed treatment choices. Eur Respir J. 2022 Jul 21;60(1):2102106. doi: 10.1183/13993003.02106-2021. PMID: 34916263; PMCID: PMC9301054.
What are some feasible physician interventions that benefit planetary health?
- Active transportation (walking and cycling)
- Plant-based dietary shifts
- Sustainable healthcare practices that reduce the environmental footprint of medical care (e.g., telemedicine to reduce unnecessary travel, reducing low-value procedures/tests, optimizing waste management)
Braithwaite J, Smith CL, Leask E, Wijekulasuriya S, Brooke-Cowden K, Fisher G, Patel R, Pagano L, Rahimi-Ardabili H, Spanos S, Rojas C, Partington A, McQuillan E, Dammery G, Carrigan A, Ehrenfeld L, Coiera E, Westbrook J, Zurynski Y. Strategies and tactics to reduce the impact of healthcare on climate change: systematic review. BMJ. 2024 Oct 8;387:e081284. doi: 10.1136/bmj-2024-081284. PMID: 39379104; PMCID: PMC11459334.
What are ways that operating rooms can be optimized regarding their environmental impact?
Recent Canadian guidelines have outlined 21 evidence-based recommendations to reduce the environmental impact of operating rooms, organized into four categories: reduce, reuse, recycle, and rethink. These recommendations address waste segregation, pharmaceutical waste reduction, reusable medical devices, specialized recycling programs, and environmentally preferable purchasing policies.
Goldman J, Pearsall EA, Liu K, De Castro C, Le N, Abbass SA, Philip R, Donahoe LL, Khalid Y, Nadler A, Vincent AD, Van Der Vyver M, Moloo H, McKellar S, Devon K, Miller FA, Ward SE. Increasing the environmental sustainability of operating rooms in Canada: an evidence-informed guideline for policy. CMAJ. 2026 Feb 8;198(5):E159-E170. doi: 10.1503/cmaj.251192. PMID: 41663140; PMCID: PMC12916213.
What are some mitigation strategies to reduce the PPE-related carbon footprint?
Specific studied strategies include domestic manufacturing, eliminating unnecessary glove use, reusing gowns and face shields, and maximal recycling.
Additionally, there is emerging decontamination technologies, such as antimicrobial photodynamic inactivation using methylene blue.
Rizan C, Reed M, Bhutta MF. Environmental impact of personal protective equipment distributed for use by health and social care services in England in the first six months of the COVID-19 pandemic. J R Soc Med. 2021 May;114(5):250-263. doi: 10.1177/01410768211001583. Epub 2021 Mar 16. PMID: 33726611; PMCID: PMC8150566.
Ludwig-Begall LF, Heyne B. aPDI meets PPE: photochemical decontamination in healthcare using methylene blue-where are we now, where will we go? Photochem Photobiol Sci. 2024 Feb;23(2):215-223. doi: 10.1007/s43630-023-00514-1. Epub 2024 Jan 2. PMID: 38165604.
What are alternative inhalers to MDIs?
Metered-dose inhalers (MDIs) generate approximately 27 times more greenhouse gas emissions than dry powder inhalers (DPIs) or soft mist inhalers (SMIs).
Feldman WB, Han J, Raymakers AJN, Furie GL, Chesebro BB. Inhaler-Related Greenhouse Gas Emissions in the US: A Serial Cross-Sectional Analysis. JAMA. 2025;334(18):1638–1649. doi:10.1001/jama.2025.16524.
Which populations are at amplified climate change associated risks?
Children, elderly, pregnant individuals, outdoor workers, and those with chronic diseases. Overall, social determinants of health lead to disproportional implications of climate change.
Romanello M, McGushin A, Di Napoli C, Drummond P, Hughes N, Jamart L, Kennard H, Lampard P, Solano Rodriguez B, Arnell N, Ayeb-Karlsson S, Belesova K, Cai W, Campbell-Lendrum D, Capstick S, Chambers J, Chu L, Ciampi L, Dalin C, Dasandi N, Dasgupta S, Davies M, Dominguez-Salas P, Dubrow R, Ebi KL, Eckelman M, Ekins P, Escobar LE, Georgeson L, Grace D, Graham H, Gunther SH, Hartinger S, He K, Heaviside C, Hess J, Hsu SC, Jankin S, Jimenez MP, Kelman I, Kiesewetter G, Kinney PL, Kjellstrom T, Kniveton D, Lee JKW, Lemke B, Liu Y, Liu Z, Lott M, Lowe R, Martinez-Urtaza J, Maslin M, McAllister L, McMichael C, Mi Z, Milner J, Minor K, Mohajeri N, Moradi-Lakeh M, Morrissey K, Munzert S, Murray KA, Neville T, Nilsson M, Obradovich N, Sewe MO, Oreszczyn T, Otto M, Owfi F, Pearman O, Pencheon D, Rabbaniha M, Robinson E, Rocklöv J, Salas RN, Semenza JC, Sherman J, Shi L, Springmann M, Tabatabaei M, Taylor J, Trinanes J, Shumake-Guillemot J, Vu B, Wagner F, Wilkinson P, Winning M, Yglesias M, Zhang S, Gong P, Montgomery H, Costello A, Hamilton I. The 2021 report of the Lancet Countdown on health and climate change: code red for a healthy future. Lancet. 2021 Oct 30;398(10311):1619-1662. doi: 10.1016/S0140-6736(21)01787-6. Epub 2021 Oct 20. Erratum in: Lancet. 2021 Dec 11;398(10317):2148. doi: 10.1016/S0140-6736(21)02429-6. PMID: 34687662; PMCID: PMC7616807.
Admissions under what specialty have been found to have the highest carbon emissions?
Notably, a study found that general internal medicine was the highest carbon-emitting specialty among all clinical specialities in secondary and tertiary care.
Begum H, Gray WK, Simpson RM, Ingleton R, Phull MK. Carbon emissions from clinical activities by speciality in secondary and tertiary care in England: an exploratory cross-sectional analysis of routine administrative data. Lancet Reg Health Eur. 2025 Jun 2;54:101333. doi: 10.1016/j.lanepe.2025.101333. PMID: 40519770; PMCID: PMC12167066.
PPE waste generation has created a significant environmental crisis, particularly during the COVID19 pandemic. Based on a study in Toronto, debris from which PPE item specifically was found to be highest when surveyed?
A Toronto study documented PPE items in surveyed areas, 44% disposable gloves, 31% face masks, and 25% disinfecting wipes.
Ammendolia J, Saturno J, Brooks AL, Jacobs S, Jambeck JR. An emerging source of plastic pollution: Environmental presence of plastic personal protective equipment (PPE) debris related to COVID-19 in a metropolitan city. Environ Pollut. 2021 Jan 15;269:116160. doi: 10.1016/j.envpol.2020.116160. Epub 2020 Dec 4. PMID: 33316501; PMCID: PMC7833877.
What are some barriers to lower-emission alternatives?
Despite their environmental advantages, DPIs and SMIs have adoption challenges including higher costs, limited formulations, and formulary restrictions.
Alkhunaizi M, Nassikas N, Eggert LE, Tirumalasetty J. Reducing Inhaler-Related Greenhouse Gas Emissions. JAMA. 2025;333(23):2051–2053. doi:10.1001/jama.2025.5942.
What are some healthcare delivery challenges related to climate change?
Supply chain disruptions during extreme weather events, power supply vulnerabilities, emergency preparedness. These are all motivators to building resilient healthcare systems.
Philipsborn RP, Sheffield P, White A, Osta A, Anderson MS, Bernstein A. Climate Change and the Practice of Medicine: Essentials for Resident Education. Acad Med. 2021 Mar 1;96(3):355-367. doi: 10.1097/ACM.0000000000003719. PMID: 32910006.
Average carbon footprint per internal medicine admission?
While specific data is limited, available evidence supports that hospital admissions generate substantial greenhouse gas emissions ranging from approximately 30kg CO2 equivalents per inpatient day in low-carbon energy settings to over 100kg CO2 equivalents per day in high-carbon energy settings.
Hemberg L, Singh J, Bentzer P. A process-based life cycle assessment of the climate impact of a Swedish intensive care unit. Sci Rep. 2025 Jun 3;15(1):19435. doi: 10.1038/s41598-025-02789-z. PMID: 40461638; PMCID: PMC12134305.
By what percentage has combining multiple mitigation strategies been found to reduced the PPE-related carbon footprint?
75% reduction compared to baseline scenarios.
Rizan C, Reed M, Bhutta MF. Environmental impact of personal protective equipment distributed for use by health and social care services in England in the first six months of the COVID-19 pandemic. J R Soc Med. 2021 May;114(5):250-263. doi: 10.1177/01410768211001583. Epub 2021 Mar 16. PMID: 33726611; PMCID: PMC8150566.
Annual inhaler emissions in the US are equivalent to approximately how many homes or gas-powered cars?
470,000 homes or 530,000 gas-powered cars.
Feldman WB, Han J, Raymakers AJN, Furie GL, Chesebro BB. Inhaler-Related Greenhouse Gas Emissions in the US: A Serial Cross-Sectional Analysis. JAMA. 2025;334(18):1638–1649. doi:10.1001/jama.2025.16524.