Kanebo Cosmetics Inc. says it has confirmed that 4,061 users of its group's skin-whitening cosmetics have suffered unwanted white blotches on their skin.

Kanebo said 8,631 people had reported developing such blotches by July 25, though that number could increase. The company issued a recall July 4 of 54 types of cosmetics products due to the risk of patchy skin whitening.

It was revealed Wednesday that Kanebo started investigating the problem two weeks after being alerted by a dermatologist that white blotches were appearing on the skin of people using the products.

Hisashi Anami, the chief of the Consumer Affairs Agency, was critical of Kanebo.

"I cannot understand why it took two weeks" to respond to the alert, Anami said Wednesday at a news conference.

Kanebo said its workers had visited 4,313 customers by Sunday who had reported developing blotches after using the products. Of the 4,061 people confirmed to have white blotches on their skin, 1,828 suffered serious symptoms, such as having more than three white blotches or blotches measuring at least 5 cm in diameter.

Meanwhile, 1,457 people showed minor symptoms and 776 had already recovered or were recovering from such symptoms, the company said.

Kanebo said it intends to cover medical costs and pay compensation. The company also said it will continue visiting customers who report blotches.

It has so far received inquiries from about 200,000 people.

As of Sunday, Kanebo had recalled about 435,000 product units, around 97 percent of those believed to have been sold, and had removed almost all of the 590,000 items that were still on store shelves.

The recalled products, including Kanebo Blanchir Superior, use a whitening chemical substance called 4-(4-hydroxyphenyl)-2-butanone, which Kanebo named Rhododenol.