The health ministry and local authorities on Saturday inspected a Kobayashi Pharmaceutical Co. factory in Osaka following reports of deaths and hospitalizations possibly linked to its red yeast rice dietary supplements.

The factory in western Japan, which was making the ingredients of the supplements, shut down in December. But the ministry and the local government decided to carry out an on-site inspection in light of the widening health problems regarding the Osaka-based company's products containing "beni-koji" red yeast rice.

The search of the Osaka factory took about four and a half hours. Kenji Yamashita, head of the company's production division, on Saturday apologized but declined to provide the details of the inspection.

Japanese health ministry officials search a Kobayashi Pharmaceutical Co. factory in Osaka, western Japan, on March 30, 2024, following reports of deaths and hospitalizations possibly linked to its red yeast rice dietary supplements. (Kyodo) ==Kyodo

Since the company moved the production of the ingredients to a factory in Wakayama Prefecture, an inspection will also be conducted there on Sunday.

Kobayashi Pharmaceutical has so far reported a total of five deaths and the hospitalizations of more than 110 people as possibly linked to the red yeast rice dietary supplements. About 680 have either seen a doctor due to health issues or wish to do so.

At a press conference on Friday, the drugmaker said puberulic acid, a natural compound made from blue mold, was detected in the supplements' ingredients and could have a connection with the health issues.

The substance is a potent antibacterial and antimalarial agent that can be toxic, according to the Health, Labor and Welfare Ministry.

Of the three types of product that have been voluntarily recalled by Kobayashi Pharmaceutical, health complaints have largely come from those who consumed the "beni-koji choleste help" manufactured after September, according to the company. The pills have been touted as products that help lower levels of LDL cholesterol, known as "bad" cholesterol.

The company rolled out choleste help in February 2021, selling around 1 million of the packages by the end of February this year.

Concerns over the beni-koji supplements surfaced last week, with Kobayashi Pharmaceutical initially announcing that 13 people who took the products developed health problems such as kidney disease.

As a supplier of beni-koji as a food ingredient, Kobayashi Pharmaceutical has also asked companies to voluntarily recall products that have used its beni-koji, with the incident affecting a wide range of products including sake, confectionery, bread and miso.

Beni-koji is rice fermented with red yeast and is used for coloring and flavoring. In East Asia, it has been touted as bringing health benefits and used in items such as alcohol.

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