Can humans be secondary consumers?

Secondary consumers include owls, bears, lions and humans – along with many other organisms, and can be considered the predators in a given ecosystem. Many secondary consumers are carnivores, some of which are eaten by tertiary consumers.

Yes. Secondary consumers are like little animals  and big, such as birds, humans, rats, etc.

bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids.