Radiation Oncology/Ecological Footprint

Ecological Footprint of Health Care

General Carbon Footprint

• University of Bergen, Norway; 2021 PMID 34711584 -- "Priority setting and net zero healthcare: how much health can a tonne of carbon buy?" (Bhopal A, BMJ. 2021 Oct 28;375:e067199.); Link
  • Proposal to use carbon as part of health care priority setting
  • Clinical decision-making; health system perspective; and a global perspective

• UK NHS; 2021 PMID 33581070 -- "Health care's response to climate change: a carbon footprint assessment of the NHS in England" (Tennison I, Lancet Planet Health. 2021 Feb;5(2):e84-e92.). Overview Link. PDF Link
  • Model using Scope 1 (direct emissions from owned or controlled sources), Scope 2 (indirect emissions from purchased electricity, heat, cooling), Scope 3 (other indirect costs associated with organization's operations, including medical equipment and food/catering, as well as staff commute), and Non-Protocol (patient and visitor travel)
  • Outcome: In 2019, NHS emissions were 25 megatones of CO2 equivalent (reduction of 26% since 1990). Footprint included supply chain (62%), direct delivery of care (24%), staff and patient/visitor travel (10%), and commissioned private health care services (4%)

• US National Expenditure Accounts
  • 2020 PMID 33284703 -- "Health Care Pollution And Public Health Damage In The United States: An Update" (Eckelman MJ, Health Aff (Millwood). 2020 Dec;39(12):2071-2079.)
    • US health care emissions 1,693 kg CO2 per person in 2018, slowly risking since 2012
    • Contribution to emissions: 1) Direct emissions from health care operations (7%), 2) Indirect emissions from purchased energy (11%), 3) Indirect emissions from supply chain (82%). Largest supply chain contribution from pharmaceuticals/chemicals, food, energy, plastics
    • Variation in state-level emissions, which were not highly correlated to quality
  • 2016 PMID 27280706 -- "Environmental Impacts of the U.S. Health Care System and Effects on Public Health" (Eckelman MJ, PLoS One. 2016 Jun 9;11(6):e0157014.). Article Link
    • Estimate of direct and indirect emissions attributable to health care sector using economic input-output life cycle assessment modeling using National Health Expenditures from 2003-2013
    • Greenhouse gas emissions 655 million metric tons CO2 equivalent (9.8% national total). Health care (36%), physician and clinical services (12%) and prescription drugs (10%) were largest categories.
    • Direct emissions from on-site operation 2.5%; majority of the emission from supplies of energy, goods, and services. Power generation (36%)
    • Additional impact in producing acid rain (12%), GHG (10%), smog formation (10%), air pollutants (9%) causing 470,000 DALYs lost. The are commensurate with 44k-98k of patients who die in hospitals from preventable medical errors
  • 2009 PMID 19903917 -- "Estimate of the carbon footprint of the US health care sector" (Chung J, JAMA. 2009 Nov 11;302(18):1970-2.)
    • US health sector contributed 8% of greenhouse gas emission nationally, and 7% of CO2 emission.

• NHS, 2016 PMID 31098080 -- "Reducing the carbon footprint of hospital-based care" (Tomson C, Future Hosp J. 2015 Feb;2(1):57-62.). Article Link

Specific Carbon Footprint

Radiation Oncology

• Princess Margaret, 2023 (2019-2021) PMID 36309074 -- "Evaluating the Short-term Environmental and Clinical Effects of a Radiation Oncology Department's Response to the COVID-19 Pandemic" (Cheung R, Int J Radiat Oncol Biol Phys. 2023 Jan 1;115(1):39-47. doi: 10.1016/j.ijrobp.2022.04.054. Epub 2022 Oct 26.)
  • Retrospective. 10,175 patients resulting in 176,423 fractions.
  • Outcome: Hypofractionation 17% to 27%. Carbon footprint reduced by 39%. Reduction in visits to outpatient clinic (39% vs 25%, SS) or ED department (6% vs 2%, SS)
  • Conclusion: Environmental benefit of hypofractionation and virtual care, with no added acute adverse events

• TARGIT-A Trial
  • Randomized trial. Traditional EBRT vs TARGIT single fraction
  • UK data; 2016 PMID 27160842 -- "Environmental and social benefits of the targeted intraoperative radiotherapy for breast cancer: data from UK TARGIT-A trial centres and two UK NHS hospitals offering TARGIT IORT" (Coombs NJ, BMJ Open 2016 May 9;6(5):e010703.) Paper link
    • Retrospective analysis. 505 UK patients with geographic data. Google Maps. Fuel efficiency of 40 mpg, CO2e ~285 g/mile.
    • Outcome: Distance travelled TARGIT mean 87 miles vs mean 392 miles (SS). CO2 emissions 24.7 kg vs 111 kg (SS). Time travelling 3 hr vs 14 hr (SS). Patients in 2 semi-rural hospitals larger journeys 753 miles, 30 hrs, and 215 kg CO2 per patient
    • TARGIT intraoperative radiotherapy significant reduces journeys for treatment and has environmental benefits
  • Global impact; 2022 PMID 36033486 -- "Global adoption of single-shot targeted intraoperative radiotherapy (TARGIT-IORT) for breast cancer-better for patients, better for healthcare systems" (Vaidya JS, Front Oncol. 2022 Aug 11;12:786515.)
    • Retrospective analysis. Data from 242 of 260 centers in 35 countries. Approximately 44,752 patients treated with TARGIT between 1998 and 2020. Travel data from the UK paper were used. Assumed 66% patients were urban (travel distance saved 305 miles) vs rural (750 miles saved)
    • Outcome: Estimate >20 million miles travel saved, representing 5.6 million kg of CO2 equivalent
    • Conclusion: TARGIT IORT estimates of ecological benefit

Cataract Surgery

• Cochin University, France; 2021 PMID 34823888 -- "The carbon footprint of cataract surgery in a French University Hospital" (Ferrero A, J Fr Ophtalmol. 2021 Nov 22;S0181-5512(21)00538-6. doi: 10.1016/j.jfo.2021.08.004.)
  • One day of surgery. Greenhouse gas emission related to patient and staff transportation, building energy consumption, and life cycle assessment (LCA) of equipment and sterilization processes
  • Outcome: LCA of disposable items was 59.5 kg CO2 per procedure. Single procedure generated 2.8 kg of CO2. Average patient transportation per procedure was 7.3 kg of CO2. Sterilization was 2.1 kg. Energy consumption of the building was 0.8 kg and staff transport 0.08 kg.
  • Conclusion: Total carbon footprint of one cataract procedure was 81.1 kg CO2 equivalent.

• University of Otago Welligton, NZ; 2021 PMID 34531593 -- "The carbon footprint of cataract surgery in Wellington" (Latta M, N Z Med J. 2021 Sep 3;134(1541):13-21.)
  • Use of Eyefficiency tool. Carbon footprint at 4 hospitals. 142 cataract surgeries.
  • Outcome: a cataract surgery produced on average 152 kg of CO2 equivalent. Greatest contribution from disposable materials and from patient travel

• Multi-institutional; 2021 PMID 34104796 -- "Improving productivity, costs and environmental impact in International Eye Health Services: using the 'Eyefficiency' cataract surgical services auditing tool to assess the value of cataract surgical services" (Goel H, BMJ Open Ophthalmol. 2021 May 20;6(1):e000642.)
  • Use of Eyefficiency tool. Carbon footprint at 9 cataract surgical facilities worldwide. 1 week or 30 consecutive cataract surgeries continuously.
  • Outcome: 475 cataract extractions (mix phacoemulsification and manual incision). Greenhouse gases ranged from 41 kg of CO2 equivalent to 130 kg CO2 equivalent
  • Conclusion: Global diversity in metrics

• University Hospital of Wales; 2013 PMID 23429413 -- "The carbon footprint of cataract surgery" (Morris DS, Eye (Lond). 2013 Apr;27(4):495-501.)
  • Component analysis for one patient, including building/energy use, travel, and procurement
  • Outcome: Carbon footprint 182 kg CO2eq. Given total 2230 patient treated in 2011, overall footprint 405.5 tonnes CO2eq. Building/energy use 36%, travel 10%, procurement 54% (medical equipment 33%).

Head&Neck Surgery

• Dalhousie University, Canada; 2021 PMID 33875009 -- "Carbon footprint reduction associated with a surgical outreach clinic" (Forner D, J Otolaryngol Head Neck Surg. 2021 Apr 19;50(1):26.)
  • Self-administered survey of 113 patient travel patterns to outreach clinic vs regional centre. 12/2019 - 02/2020.
  • Outcome: Own car (86%). Median distance to outreach clinic 29 kg vs regional centre 327 km. Mean CO2 emission 117 kg to 144 kg per person; equivalent to individual's 2.5% of annual carbon footprint.
  • Conclusion: Surgical outreach clinics decrease carbon footprint associated with patient travel

Hysterectomy

• University of Pittsburgh; 2015 PMID 25517602 -- "Environmental impacts of surgical procedures: life cycle assessment of hysterectomy in the United States" (Thiel C, Environ Sci Technol. 2015 Feb 3;49(3):1779-86.) Link
  • LCA analysis
  • Outcome: Different mix of hysterectomies, impact ~400 kg CO2 per case

Operating Rooms

• Multi-Institutional, Canada; 2017 PMID 29851650 -- "The impact of surgery on global climate: a carbon footprinting study of operating theatres in three health systems" (MacNeill AJ, Lancet Planet Health. 2017 Dec;1(9):e381-e388.)
  • Three academic hospitals in Canada (Vancouver General Hospital), USA (University of Minnesota) and UK (John Radcliffe), 1 year period in 2011
  • Outcome: Total annual footprint 5,188 tons kg at JRH, 4,182 tons kg at UMMC, 3,219 tons kg at VGH. Per unit area in m2 JRH 1,702 kg/m2, UMMC 2,284 kg/m2, VGH 1,951 kg/m2. Per operation JRH 173 kg, UMMC 232 kg, VGH 146 kg. Largest sources of consumption anaesthetic gases and energy consumption. Surgical theatres 3x-6x more energy-intense than hospitals as a whole due to HVAC requirements.

General Surgery Practice

• University of Leeds; 2013 PMID 23998839 -- "Carbon footprint of patient journeys through primary care: a mixed methods approach" (Andrews E, Br J Gen Pract. 2013 Sep;63(614):e595-603.) Link
  • 650 daily journeys. 306 patient filled travel survey in March 2012.
  • Outcome: 55% by car (62% <2 miles), 30% walked (64% <1 mile), 10% bus. Total carbon footprint 63 tonnes CO2 per year
  • Comment: PMID 24152453 -- "Carbon footprint of patient journeys" (Clayton M, Br J Gen Pract. 2013 Oct;63(615):517. Paper link
    • Patient choice regarding seeing physicians far away

Minimally Invasive Surgery

• University of Western Ontario, Canada; 2012 PMID 22845049 -- "Environmental impact of minimally invasive surgery in the United States: an estimate of the carbon dioxide footprint" (Power NE, J Endourol. 2012 Dec;26(12):1639-44.)
  • Retrospective. Incremental use of CO2 in minimally invasive surgery (MIS). Scope 1 emissions was CO2 used during surgery. 2.5 million procedures in the US in 2009 identified.
  • Outcome: Scope 1 emissions 303 tonnes CO2. Scope 2 and 3 emissions 355,621 tonnes including gas transport and biomedical waste
  • Conclusion: Direct CO2 use minimal, but indirect CO2 use in minimally invasive surgeries large environmental impact

• Wansbeck Hospital, Newcastle, UK; 2008 PMID 18095020 -- "The carbon footprint of laparoscopic surgery: should we offset?" (Gilliam AD, Surg Endosc. 2008 Feb;22(2):573.) Paper link
  • Retrospective. Laparoscopic procedures performed. CO2 cylinders identified.
  • Outcome: Surgeries 1,629. OR time 1.01 hours. CO2 Cylinders 415. Operative time per cylinder 4 hours. Each cylinder contributes 0.0009 tones CO2. Total 450 liters = 0.0009 tonnes
  • Conclusion: Direct CO2 impact minimal

The aim of this study was to estimate the effect that the expansion of laparoscopic surgery has had on global

Renal Service

• MetroHealth System, Cleveland, Ohio; 2022 PMID 35654600 -- "Sources of Variation in the Carbon Footprint of Hemodialysis Treatment" (Sehgal AR, J Am Soc Nephrol. 2022 Jun 2
  • Retrospective. 15 Ohio hemodialysis facilities, in 2020.
  • Outcome: Annual emissions ~769 tonnes CO2e, and 59 kg CO2e per treatment. Largest contributors patient/staff transportation 28%, electricity 27%, natural gas 15%. Equivalent to 93 home energy use
  • Variability: 3x across facilities; largest contributor transportation
  • Conclusion: Similar treatments in similar geographic region show substantial variation in carbon footprint

• Hassan II University, Cacablanca, Morocco; 2021 PMID 33159433 -- "Carbon footprint of a hemodialysis unit in Morocco" (Mtioui N, Ther Apher Dial. 2021 Oct;25(5):613-620.
  • Retrospective, 2019 data. 3x4 hours, 424 m2, 24 generators, 80 patients
  • Outcome: 409 tonnes CO2e per year; or 5.11 tonnes CO2e per patient per year. Largest contributions electricity (28%), equipment purchase/service (27%), staff and patient travel (22%)

• Dorset County Hospital, UK; 2010 PMID 20719900 -- "The carbon footprint of a renal service in the United Kingdom" (Connor A, QJM. 2010 Dec;103(12):965-75.)
  • Activity data for building energy use, travel, and procurement
  • Outcome: Carbon footprint 3,006 tonnes CO2 eq per year; building energy 13%, travel 15%, procurement 72% (pharmaceuticals 35%, medical equipment 25%). Emissions 161 kg CO2 eq per bed per day inpatient and 22 kg outpatient.

• Geelong Hospital, Australia; 2013 PMID 23731962 -- "The carbon footprint of an Australian satellite haemodialysis unit" (Lim AEK, Aust Health Rev. 2013 Jun;37(3):369-74.)
  • Suburban satellite hemodialysis unit in 2011.
  • Outcome: Annual per-patient 10.2 tonnes CO2 equivalent. Contributions pharmaceuticals 36%, medical equipment 23%. Contribution of water (4% to 12%) and electricity (5% to 19%) varies throughout Australia

Meta-Analysis

• Dalhousie University, Canada; 2021 PMID 34251875 -- "Operating in a Climate Crisis: A State-of-the-Science Review of Life Cycle Assessment within Surgical and Anesthetic Care" (Drew J, Environ Health Perspect. 2021 Jul;129(7):76001.)
  • Overview of life cycle assessment for surgery and anesthesia. 44 studies eligible
  • Outcome: Annual impact between 3,200,000 kg and 5,200,000 kg of CO2. Per case, range 6 kg to 1,007 kg CO2 equivalent. Main emission sources anesthetic gases, single use equipment, HVAC

• Wichita State; 2020 no PMID -- "Quantifying hospital services by carbon footprint: A systematic literature review of patient care alternatives" Alshqaqeeq F, Resources, Conservation and Recycling, 2020 March. Link
  • Peer reviewed articles Jan 2000 - Dec 2016. 48 studies identified. Environmental scopes: 1) Travel-related energy, 2) Direct energy, 3) Procedural goods and equipment energy

• NHS Systematic Review; 2020 PMID 32516230 -- "The Carbon Footprint of Surgical Operations: A Systematic Review" (Rizan C, Ann Surg. 2020 Dec;272(6):986-995.) Link
  • 8 eligible publications.
  • Outcome: Carbon footprint of single operation range 6 kg to 814 kg of CO2 equivalent. Major sources were electricity use and consumables

• James Cook University, Australia; 2012 PMID 23078475 -- "The energy burden and environmental impact of health services" (Brown LH, Am J Public Health. 2012 Dec;102(12):e76-82.). Link
  • 38 publications
  • Review of National Level Health Service Emissions (16 studies); Hospital / Hospital Facilities (8 studies); Surgery (4 studies); Water consumption (4 studies)

Telemedicine

• UK NHS Lothian; 2022 PMID 35134839 -- "Calculating the carbon footprint of a Geriatric Medicine clinic before and after COVID-19" (Bartlett S, Age Ageing. 2022 Feb 2;51(2). Paper link
  • Retrospective. 48 patient prior to social distancing and 39 patients after social distancing (7 seen via telemed). Estimates for virtual (0.99 kg CO2e) and face-to-face (4.82 kg CO2e) consults, which included use of PPE. Scope 2 and Scope 3. UK petrol car 0.3 kgCO2e per mile. UK grid 0.233 kgCO2e per kWh. PPE 0.15 kgCO2e per outfit. Video call 2.9 kgCO2 per hour
  • Outcome: Mean travel distance 4.7 miles. Hybrid (face-to-face + telemed) patient travel 24 kg CO2e vs face-to-face 42 kg CO2e. Clinic overhead ~30 kg CO2e.
  • Conclusion: Environmental benefit of hybrid model with telemedicine consultations

• St James Hospital, Dublin, Ireland; 2021 PMID 34464571 -- "Time, cost and carbon-efficiency: a silver lining of COVID era virtual urology clinics?" (Croghan SM, Ann R Coll Surg Engl. 2021 Sep;103(8):599-603.)
  • Retrospective. 1,016 consultations, 72% virtual.
  • Outcome: Travel saving 93.8 miles round trip. Cost saving 25.98 pounds. CO2e reduction 6.1 tonnes
  • Conclusion: Virtual clinics provide efficiency across number of domains

• University of Southampton, UK; 2021 PMID 35372776 -- "The environmental impacts of telemedicine in place of face-to-face patient care: a systematic review" (Ravindrane R, Future Healthc J. 2022 Mar;9(1):28-33.) Paper link
  • Systematic review. 14 studies.
  • Outcome: All studies found benefit

• University of Cambridge, UK; 2021 PMID 33791483 -- "Does telemedicine reduce the carbon footprint of healthcare? A systematic review" (Purohit A, Future Healthc J. 2021 Mar;8(1):e85-e91. Paper link
  • Systematic review. 14 studies.
  • Outcome: savings ranged from 0.7 to 372 kg CO2e, but were highly context specific. The highest was airplane travel saved from Scotland to California H&N surgeon, who watched nasopharyngoscopy virtually

• Sorbonne University; 2021 PMID 34454847 -- "Positive environmental impact of remote teleconsultation in urology during the COVID-19 pandemic in a highly populated area" (Filfilan A, Prog Urol. 2021 Dec;31(16):1133-1138). Paper link
  • Prospective, 2 weeks, patients scheduled for remote teleconsultation. 80 patients. Conversion 1kWh = 0.1 kg CO2e. 1 km car = 0.175 kg CO2e, while 1 km metro = 0.003 kg CO2e.
  • Outcome: Face-to-face would have resulted in 84 km per patient, total 6699 km. Cars usual mode of transport (97%). CO2 avoided was 1141 kg CO2e (99% reduction).
  • Secondary outcomes: Patients saved 974 euro on transport and 112 hours travel time (1.4 hours per patient). Good experience with teleconsultation in 86%
  • Conclusion: Teleconsultation reduces environmental impact

• University of Cambridge; 2021 PMID 33791483 -- "Does telemedicine reduce the carbon footprint of healthcare? A systematic review" (Purhoit A, Future Healthc J. 2021 Mar;8(1):e85-e91.)
  • Systematic review. CO2 savings per consultation 0.7 - 372 kg, highly context specific. Telemedicine unit energy use very low

• University Health Network, Toronto; 2010 PMID 20958198 -- "The impact of telemedicine on greenhouse gas emissions at an academic health science center in Canada" (Masino C, Telemed J E Health. 2010 Nov;16(9):973-6.)
  • Travel distances for each appointment evaluated by Google Maps
  • Outcome: Avoided travel 757,234 km; equivalent to 185 metric tons of CO2e. Videoconference unit consumption 42 kg CO2. Air pollutants 360 kg avoided.

• Umea University, Sweden, 2014 PMID 25188322 -- "Carbon footprint of telemedicine solutions--unexplored opportunity for reducing carbon emissions in the health sector" (Holmner A, PLoS One. 2014 Sep 4;9(9):e105040.) Paper link
  • Lifecycle inventory of 2 rehab units in 2012. 238 telemedicine visits. One hour telemed appointment between 1.9 and 8.4 kgCO2e, depending choice of telemed hardware, bandwidth, meeting duration
  • Outcome: Avoided travel distance 82,310 km. Avoided carbon cost 602 kgCO2e (~98% reduction)
  • Conclusion: Telemedicine is a potent carbon reduction strategy

Environmental Impact

• The Lancet Countdown
  • 2021 PMID 34687662 -- "The 2021 report of the Lancet Countdown on health and climate change: code red for a healthy future" (Romanello M, Lancet. 2021 Oct 30;398(10311):1619-1662.) Link
  • 2020 PMID 33278353 -- "The 2020 report of The Lancet Countdown on health and climate change: responding to converging crises" (Watts N, Lancet. 2021 Jan 9;397(10269):129-170.)
  • 2019 PMID 31733928 -- "The 2019 report of The Lancet Countdown on health and climate change: ensuring that the health of a child born today is not defined by a changing climate" (Watts N, Lancet. 2019 Nov 16;394(10211):1836-1878.)
  • 2018 PMID 29096948 -- "The Lancet Countdown on health and climate change: from 25 years of inaction to a global transformation for public health" (Watts N, Lancet. 2018 Feb 10;391(10120):581-630.) Link
  • 2017 PMID 27856085 -- "The Lancet Countdown: tracking progress on health and climate change" (Watts N, Lancet. 2017 Mar 18;389(10074):1151-1164.)
  • 2015 PMID 26111439 -- "Health and climate change: policy responses to protect public health" (Watts N, Lancet. 2015 Nov 7;386(10006):1861-914.) Link
    • Formation of The Lancet Commission on Health and Climate Change

• Northeastern University/Yale University; 2018 PMID 29072942 -- "Estimated Global Disease Burden From US Health Care Sector Greenhouse Gas Emissions" (Eckelman M, Am J Public Health. 2018 Apr;108(S2):S120-S122.)
  • Estimate of disease burden from US health care sector LCA emissions of 614 million tons of CO2 equivalent in 2013
  • Outcome: 123,000 to 381,000 disability adjusted life-years of future health damage; malnutrition largest damage