NHK has learned that a Japanese research institute has confirmed the presence of at least two additional unintended substances in samples of the "beni-koji" ingredient used in recalled health supplements. The supplements were made by Kobayashi Pharmaceutical.
The products containing the beni-koji ingredient, or rice fermented with red yeast, have been linked to numerous reports of kidney problems among people who ingested them.
The health ministry has obtained samples of the beni-koji material produced over the past three years from Kobayashi Pharmaceutical. The National Institute of Health Sciences has been analyzing the samples.
Sources say the research institute confirmed the presence of at least two unintended substances in the samples of the beni-koji ingredient linked to health complaints.
They say it is not known whether these compounds caused any harm. The health ministry is trying to identify them.
The sources say the substances are different from puberulic acid, a component earlier detected by Kobayashi Pharmaceutical, which can be generated by blue mold.
The drugmaker said that the dietary supplements have been linked to at least five deaths. It said that as of Thursday, 240 hospitalizations have been reported.