The gummies the man handed out were a product manufactured by a company based in Osaka. The ingredients printed on a label included HHCH, or hexahydrocannabihexol, according to the Tokyo metropolitan and Osaka governments. HHCH is a synthetic substance with a structure similar to tetrahydrocannabinol, or THC, a constituent of cannabis, and can cause effects such as hallucinations and memory impairment. While THC is banned in Japan, HHCH is not, according to the health ministry.