YSPH EHS - Yale SUPERFUND RESEARCH CENTER Seminar: "Edible-Dye Enhanced Solar Disinfection"

NOTE: EHS 525 students are required to attend in person. Others are invited to attend in person, but may also attend via Zoom.

SPEAKER: Jaehong Kim, PhD - Henry P. Becton Sr. Professor, Chemical & Environmental Engineering - Yale School of Engineering and Applied Science

TITLE: "Edible-Dye Enhanced Solar Disinfection"

ABSTRACT: The rural developing world faces disproportional inequity in drinking water access, where point-of-use water treatment technologies often fail to achieve adequate levels of pathogen removal, especially for viruses. Solar disinfection (SODIS) is practiced because of its universal applicability and low implementation cost, though the excessively long treatment time and lack of safety indication hinder wider implementation. This study presents an enhanced SODIS scheme that utilizes erythrosine – a common food dye – as a photosensitizer to produce singlet oxygen for virus inactivation and to indicate the completion of water disinfection through photobleaching color change. Experimental results and predictions based on global solar irradiance data suggest that over 99.99% inactivation could be achieved using erythrosine dye within 5 minutes in the majority of developing countries, reducing the time for SODIS by two orders of magnitude. Preserving the low cost of traditional SODIS, erythrosine embodies edible dye-enhanced SODIS, an efficient water disinfection method that could potentially be used by governments and non-governmental organizations to improve drinking water quality in rural developing communities. This talk also summarizes our recent efforts to explore plant-extracted photosensitizers to advance this concept for applications in more realistic settings.

YSPH values inclusion & access for all participants. If you have questions about accessibility or would like to request an accommodation, please contact Lorena Bedoya at lorena.bedoya@yale.edu by Tuesday, September 9, 2025.