Estimating CO₂ emissions from international medical electives: a literature review and quantitative analysis

Electives are short placements during medical school lasting 2-8 weeks, serving as an opportunity to engage with different healthcare systems and cultures and to travel overseas. However, amid increasing alarm about climate change, interest in the sustainability of electives and alternative elective formats are gaining attention.

A scoping review of MEDLINE, Embase, ERIC, Web of Science SCOPUS, WHO Globus Index Medicus and Scielo was conducted with double-blind screening to identify previous efforts to quantify carbon costs of electives. To quantify the carbon dioxide (CO₂) emissions of electives, we created an approach based on the fuel efficiency of aircraft used for long-haul travel, distances from the UK to popular elective destinations and the average occupancy rates of aeroplanes. These results were compared with results from seven existing resources: MyClimate, ICAO, Google Flights, C Level and EcoTree.

The review did not identify any previous studies estimating the environmental costs of medical student electives. All of the 7,575 records revealed by the database search were excluded following full-text screening. Our estimates of the CO₂ emissions from round-trip flights from Heathrow Airport, London, UK to the 10 most popular elective destinations were: Australia: 2,995 kg/person, USA: 1,039 kg/person, New Zealand: 3,316 kg/person, Canada: 941 kg/person, India: 1,185 kg/person, South Africa: 1,705 kg/person, Malaysia: 1,867 kg/person, Tanzania: 1,322 kg/person, Ireland: 79 kg/person.

This is the first study to quantify the carbon footprint of international medical electives. Our bespoke calculations, which generally agree with the results from established tools, reveal that CO₂ emissions from international travel for electives are substantial, compared to the average annual CO₂ emissions of 7,000 kg per person in the UK. This study provides evidence to motivate the design and delivery of alternative elective programmes.