Independent Investigation Examines Merino Wool Content Claims in Products Sold on Amazon

Laboratory analysis of multiple Amazon products marketed as merino wool identified discrepancies between labeling claims and measured fiber content across several brands.

June 2026 — An independent investigation conducted by textile researcher Anna McCarthy examined a wide range of apparel products sold on Amazon and marketed as containing merino wool. The review included base layers, T-shirts, long-sleeves, underwear, socks, and other wool garments purchased from various brands available to U.S. consumers.

The investigation was launched following observations that some products advertised as merino wool appeared inconsistent with the performance characteristics typically associated with genuine merino fiber. To evaluate these concerns, selected products were purchased through Amazon and submitted for independent laboratory analysis using recognized textile testing methods.

According to laboratory reports obtained during the investigation, numerous tested products showed differences between the fiber content claimed on product labels and the fiber composition identified through independent analysis.

Among the brands included in the review were FORVEVO, BEENIUBEE, CAOZITOU, Bobelle Wear, SUNCHIRI, and YESWEL. Multiple products from these brands were selected for independent laboratory analysis as part of the investigation. Rather than being limited to a single product category, the discrepancies were observed across various apparel types, suggesting that the issue may extend beyond isolated items.

One example involved a YESWEL garment sold on Amazon and marketed as containing 100% merino wool. The product listing reviewed during the investigation can be found at:

Another example involved FORVEVO Merino Wool Underwear Men's Boxer Briefs, a product sold on Amazon and marketed as 100% merino wool. The product listing reviewed during the investigation can be found at:

A third example involved the product "BEENIUBEE 2 Pack Merino Wool T-Shirt for Men, Wool Short Sleeve Base Layer, Breathable Lightweight Undershirt" sold on Amazon:

During the course of the investigation, researchers also observed that while references to "100% Merino Wool" were removed from the Amazon product listing, the same claim remained on the garment label attached to the tested product. According to the investigation, this resulted in a difference between the information presented on the marketplace listing and the information displayed on the product itself at the time of review.

According to the investigation, this was not an isolated case. Multiple products across several brands included in the review demonstrated differences between claimed and measured fiber composition, although the extent of those differences varied by product category and individual sample.

The testing was performed by an independent textile laboratory using industry-standard fiber analysis methods. The investigation reviewed marketplace listings, garment labels, and laboratory findings for numerous products purchased through Amazon.

Merino wool has become increasingly popular among consumers seeking natural temperature regulation, moisture management, odor resistance, and comfort. As demand for merino apparel continues to grow on Amazon and other online marketplaces, accurate fiber-content labeling remains an important factor in helping consumers make informed purchasing decisions.

"Consumers purchase merino wool products because they expect specific performance characteristics associated with the fiber. Accurate fiber-content disclosure is essential for informed purchasing decisions and for maintaining trust within the merino wool category."

The report does not draw conclusions regarding the cause of the discrepancies. Its findings are limited to the products tested and the laboratory results obtained during the investigation.

Additional brands and product categories may be included in future testing as the research continues. The full report, including testing methodology and supporting documentation, is available upon request.