Bamboo cups were considered the big sustainability hype. Meanwhile, many test institutes warn against them. The background is obvious - "Bamboo alone does not make a cup"(Test.de, Bambusbecher im Test, 23.07.19).To make cups, bamboo fibers are bonded with glue, which is the only way to create stability. This glue contains melamine and formaldehyde, both of which are released in high quantities, especially in connection with hot drinks. Sustainability then unfortunately quickly becomes a ticking time bomb...A good alternative to disposable cups is stainless steel, robust, beautiful and harmless & sustainable.
