Chronological Overview of the Red Koji Incident Explained by Japan's Ministry of Health

Overview of the Red Koji Incident

The Red Koji incident has raised significant concerns regarding health safety in Japan. This article systematically organizes the explanations provided by the Ministry of Health, Labour and Welfare (MHLW) about the incident, establishing a clear timeline of events from March 2024 to July 2026. The organization of this information aims to clarify the nature of the incident as responses were made public.

Timeline of Events

1. March 2024: Following multiple requests for public information, the MHLW published information relating to the Red Koji incident. This included details about potential health impacts from products affected, and reports from Kobayashi Pharmaceutical Co. regarding findings.

2. March 28, 2024: An investigative meeting of the Pharmaceutical and Food Safety Council acknowledged that unexpected substances, named Puberulic Acid, were detected in batches alleged to have caused health issues. This revelation was made by representatives of Kobayashi Pharmaceutical.

3. March 29, 2024: The MHLW announced the potential association of Puberulic Acid with kidney disease based on reports provided by Kobayashi Pharmaceutical. This statement was careful not to establish definitive causation as it used the term ‘possibility.’

Relationship with 2026 Responses

Fast forward to 2026, the MHLW asserted that there was no public declaration identifying Puberulic Acid as a causative substance for health damages. This position aligns with their earlier statements from 2024, echoing a lack of formal acknowledgment of health causation.

However, the assertion by Kobayashi Pharmaceutical regarding the identification of Puberulic Acid prompts questions about whether supporting documents substantiating their claims were submitted to the MHLW. Corresponding requests for access to these documents yielded responses indicating that no such records were created or maintained, raising concerns over documentation and transparency.

The MHLW’s response dated July 29, 2026, detailed various types of documents related to the incident, which, according to the ministry, were neither created nor in their possession. This included scientific test results concerning the presence of Puberulic Acid in red koji or related materials. Despite the extension of decision deadlines, the lack of documentation sparked further inquiries and dissatisfaction.

Key Points Covered and Unknowns

This article delineates both what was revealed and what was omitted regarding the incident:

- The outlined timeline from March to September 2024 captures the narratives shared by MHLW, clarifying contentions stemming from their communications with Kobayashi Pharmaceutical.
- The 2026 responses added layers of complexity since they indicated a lack of documentation regarding the supportive claims, remaining mute on the scientific validity of the findings.

However, this overview does not address:

- The implications of the absence of administrative documents, as it does not comment on the actual existence of scientific knowledge surrounding the claims.
- The document also refrains from evaluating the credibility of academic studies regarding Puberulic Acid or analyses performed by other institutions.
- Specifically, there is no assignment of responsibility to any individuals or entities involved in the incident.

Moving forward, continuous verification of facts by concerned parties, including public inquiries and scrutiny of governmental processes, remains essential for transparency.

Company Position

As a food manufacturer situated in Hayashima, Okayama, our company, Kousei Club Ltd., produces smoked food products (Kurashiki Sausages). Although unrelated to the source of raw materials implicated in the Red Koji incident, we have been adversely affected by confusion among product categories and continue to pursue fact-checking efforts related to the circumstances surrounding the incident.