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Although I am not familiar with plants for Cham vivariums, it would be fair to assume that the plants are safe to use since most Toads are strictly insectivores and wouldn't even bother eating the plants. As long as the plants don't contain any pesticides/harmful chemicals or parasites, I don't really see a problem with using them. Plus, if their safe for Chams, then it would probably be safe for Toads.