In the case of people who took Kobayashi Pharmaceutical's supplements developing kidney disease, unexpected ingredients were mixed in during the manufacturing process of "red yeast rice raw material" The company keeps samples of the red yeast Rice raw material manufactured at its Osaka factory for each lot of a certain amount. It is assumed that samples from 10 lots out of 88 lots manufactured in the past year appear to be pueruric acid.
Analyzing samples during production is expected to provide clues as to which process the contamination occurred.