Japan is a volcanic hotspot, with 7 percent of all the world's volcanoes. The archipelago actually contains 110 active volcanoes, and throughout history, Japan has been at the mercy of the terrifying power of volcanoes.

Breath mints, sprays and countless other products that tackle body odors offer evidence of widespread concern about smells. Japan has certified professionals who investigate offensive odors, and even a fire alarm that uses the power of smell. This time on Japanology Plus, our subject is smells. We explore how the Japanese relate to different aromas. Our expert guest is Masahiro Watanabe, an expert on smells who has studied their role in Japanese culture and business. And in Plus One, the ABCs of smell sleuthing.