Quantifying the climate benefits of a virtual versus an in-person format for an international conference.

BACKGROUND: Academic institutions across the globe routinely sponsor large conferences. During the COVID-19 pandemic, many conferences have used all- or partially virtual formats. The conversion of the 2021 Consortium of Universities for Global Health (CUGH) conference, originally planned in-person for Houston, TX USA to an all-virtual format provided an opportunity to quantify the climate-related impacts of in-person versus virtual conferences. METHODS: From the 2021 CUGH conference registration data, we determined each registrant's distance from Houston. Using widely available, open-source formulas, we calculated the carbon footprint of each registrant's round-trip drive or flight had they traveled to Houston. We assumed that registrants traveling more than 300 miles would have flown, with the remainder traveling by automobile. RESULTS: Of 1909 registrants, 1447 would have traveled less than 4000 miles, and 389 would have traveled more than 10,000 miles round trip. Total travel-related carbon emissions were estimated at 2436 metric tons of CO2, equivalent to the conservation of 2994 acres of forest for a year. CONCLUSIONS: Organizations can now readily quantify the climate cost of annual conferences. CUGH's annual international conference, when held in-person, contributes significantly to carbon emissions. With its focus on promoting global health equity, CUGH may play a lead role in understanding the pros and cons for planetary health of in-person versus virtual conferences. CUGH and other organizations could routinely measure and publish the climate costs of their annual conferences.

Environmental and health outcomes of single-use versus reusable duodenoscopes.

BACKGROUND AND AIMS: The large-scale effects of duodenoscopes on the environment and public health have not been quantified. Our aim was to perform an exploratory life cycle assessment comparing environmental and human health effects of single-use duodenoscopes (SDs) and reusable duodenoscopes (RDs). METHODS: We evaluated 3 duodenoscopes: conventional RDs, RDs with disposable endcaps, and SDs. The primary outcomes were impacts on climate change and human health, complemented by multiple environmental impacts. RESULTS: Performing ERCP with SDs releases between 36.3 and 71.5 kg of CO2 equivalent, which is 24 to 47 times greater than using an RD (1.53 kg CO2) or an RD with disposable endcaps (1.54 kg CO2). Most of the impact of SDs comes from its manufacturing, which accounts for 91% to 96% of its greenhouse gas emission. The human health impact of RDs becomes comparable with the SD lower bound if disposable endcaps or other design modifications can reduce serious infection rates below a target rate of 23 cases per year (.0046%). CONCLUSIONS: Although SDs may provide incremental public health benefit compared with RDs, it comes at a substantially higher cost to the environment. As infection rates continue to decrease from more regimented cleaning protocols and enhanced designs such as disposable endcaps to facilitate cleaning, the negative impact to human health from contaminated RDs could be comparable with SDs.