Oh Darn!  Of course this study used high human doses in the study. Dogs and cats are sensitive to the stimulant ingredients in teas, coffee and Chocolate, caffeine, theobromine, and theophylline. While we concentrate on the ECCG and other “polyphenols” in green tea for the  beneficial effects in  human and rat health, we neglect the other chemicals that may cause harm in Carnivore species.

Exposure and toxicity of green tea polyphenols in… [Toxicology. 2009] – PubMed – NCBI.