Mrs. Minh Ngọc is Arndt Schimmelmann’s bilingual Vietnamese wife who loves traveling with her husband. In 2013, Arndt and Minh Ngọc took part in the International Symposium on Large Igneous Provinces of Asia in Hanoi, Vietnam, where the Schimmelmanns met and talked to Dương Nguyễn-Thùy – a young lecturer and petrologist/geochemist at Vietnam National University who happened to be a conference organizer. Dương initially hesitated to engage with Indiana University in a research project. But Minh Ngọc and Arndt did not give up. With Minh Ngọc‘s persuasion in both Vietnamese and English, Dương began planning for international research in 2014, which grew into a number of successful collaborative research projects.
In May 2015 the first joint field work targeted caves on Cát Bà island (Hải Phòng city) and in the Đồng Văn Karst Plateau Geopark (Hà Giang Province) to measure methane in cave air.
With the expansion of our methane research project, Dương invited several Vietnamese collaborators and included graduate students from her faculty at VNU. The group at large needed a fitting name. Dương and her VNU colleague Hướng founded the EOS Research Group. Over the years, Arndt and Minh Ngọc visited occasionally to work with EOS group members and to train EOS students. Our collaboration within a close network of friends and family builds on essential virtues of the Vietnamese culture that makes our success possible.
In March 2016, Arndt and Minh Ngọc joined the EOS team during field work in rural northern Vietnam where deforestation and poverty often necessitate human habitation in ‘mud houses’. We noticed that regional soil in walls and floors contains enough natural radioactivity to emit hazardous radon levels far exceeding EPA safety thresholds. Especially the radon-220 isotope with a short half-life of ca. 55 seconds poses a health hazard that cannot be mitigated by venting of room air. Radon-220 diffuses out of porous mud into room air. Human inhalation and a chain of radioactive decay reactions of radon and its metallic daughter products can induce lung cancer.
More than half a billion people worldwide live in dwellings that are partially constructed with earthen walls. The reason for Vietnamese mud house construction is poverty and the low price of construction. The situation may be different in other developing countries. The situation is again altogether different in developed countries like in Germany where the inhabitants of houses with earthen walls want to be “green” and may indeed treasure the ‘natural appearance’. We need to first generate awareness that a radiation safety problem exists when earthen walls emit radon isotopes.
In late 2016, Arndt and Minh Ngọc returned to Vietnam and joined our EOS team to visit an authentic ‘mud house’ in a village in Hà Giang Province close to the Chinese border. Despite the time-consuming travel from Hà Nội to Hà Giang and major problems with entry permits to the restricted border region, our group successfully completed three days and nights of radiation safety experiments in a mud house.
We developed and successfully tested a novel method to mitigate the exhalation of thoron into the room air in soil-built houses. The radioactivity in room air near walls (where people sleep at night) decreased from hazardous levels to below detection limit. Our method of mitigating the thoron radiation geohazard is affordable, sustainable, socially acceptable, non-toxic, and can be applied with partially recycled resources that are readily available in most developing countries.
The project is dear to the hearts of EOS members. Arndt and Minh Ngọc are convinced that we can help many people all over the world to live healthier lives.
Minh Ngọc convinced the EOS group that we should help improve the lives of children in economically disadvantaged areas. While the group was planning science, Minh Ngọc busily searched for winter clothing and school supplies at wholesale prices in Hanoi. Outreach activities in mountain villages mainly targeted elementary schools serving primarily minority children in Hà Giang Province. Our outreach efforts were coordinated with regional and local governments and were assisted by the schools’ principals and teachers. This way we also established personal contacts and reliable logistic support for our research in the field.
Geosciences are improving the lives of people in Vietnam