Two Japanese firms claimed one sheet captured 260,000 dust mites — with no basis

Ismile Co., Ltd. and Smile Communications Co., Ltd. sold the Sayonara Danny range of mite-capture and allergy-mist products, advertised with claims such as 'a three-dimensional mite-capture sheet that captures a remarkable 250,000 mites with one sheet', 'capture power of 260,000 mites per sheet', 'decomposes allergenic substances' and 'a mite-repelling effect lasting about one month'.

The companies could not produce a reasonable basis behind these figures. The claimed capture counts, the allergy-molecule decomposition and the one-month repellent effect were presented to consumers as if they were verified performance.

Because the performance claims were markedly better than the products actually delivered, the Consumer Affairs Agency found a violation of Article 5(1) of the Premiums and Representations Act (quality misrepresentation). On 14 March 2025 it issued corrective orders under Article 7(1) against both firms.

The case is a Japanese example of a wellness product marketing vein where a precise-sounding number — 250,000, 260,000 — made an unproven claim seem mechanical and trustworthy.