Of Stones and Health: Medical Geology in Sri Lanka

Abstract

Geoscientists are usually known for their studies of rocks and minerals and the distributions of these on Earth, but this group of scientists has been expanding its discipline into surprising new territory by linking geology with human and animal health. Known as medical geology, this emerging specialty is gaining momentum. Chandra Dissanayake, professor of geology at the University of Peradeniya, Sri Lanka, outlines some of the major areas of medical geology in both his homeland and beyond, covering topics such as the link between naturally occurring fluoride in drinking water and a disfiguring tooth condition; global health risks due to iodine deficiency; the widespread practice of eating dirt; the potential for hard water to serve protective roles against cardiovascular disease; and the apparent paradox that people living in regions marked by high levels of natural radioactivity do not seem to suffer adverse health effects from their exposure. Because people must interact with their geological surroundings, discoveries made by medical geologists can have enormous consequences for the well-being of people all over the world. All essays and interactive features appearing in this series can be found online atwww.sciencemag.org/sciext/globalvoices/