NIHS Publishes Info as 'Information on Causative Substance'; MHLW States 'No Official Announcement of Puberulic Acid as Causative Substance' - Open Letter Sent to NIHS Regarding the Positioning of the Puberulic Acid Announcement -

Kunsei Club Co., Ltd. has sent an open letter to the National Institute of Health Sciences (NIHS) due to identified discrepancies between the NIHS's announcements and administrative documents from the Ministry of Health, Labour and Welfare (MHLW) regarding the status of 'Puberulic Acid' in the Benikoji-related case. The deadline for a response is June 4, 2026.

■ Questions for Public Inquiry

■ Question 1: Location of Responsibility

The NIHS has published papers and reports implying that Puberulic Acid is the causative substance in this case, whereas the MHLW has stated that it has never officially announced it as the causative substance.

Based on whose decision or instructions were these NIHS announcements made?

■ Question 2: Traceability of Samples

We request the disclosure of the following information for all samples used by the NIHS for identification and analysis:

- Source (provider or collection site)

- Acquisition date

- Sample management history (lot number, storage conditions, transfer records, etc.)

[Deadline for Response] Thursday, June 4, 2026

We request that the response to this inquiry be submitted in writing by Thursday, June 4, 2026. If a response is not received by the deadline, we will consider necessary actions, including making the situation public.

■ Our Perspective

This is a critical social issue affecting product recalls, company name disclosures, and consumer perception. Clarifying the entity responsible for scientific judgment is essential for preventing recurrence and ensuring transparency in food administration.

This issue goes beyond academic debate and directly impacts social aspects such as decisions on product recalls, the disclosure of company names, and consumer safety perceptions. Currently, there is a structural gap where:

- The government denies official certification of the causative substance.
- The research institution has released content that can be interpreted as identifying a causative substance.

As a result, many food businesses are suffering serious damages while the responsibility for scientific judgment remains unclear.

We believe it is essential to clarify the source of scientific evidence and the location of responsibility to properly resolve this case and restore the culinary value of Benikoji. We will continue to verify the facts.