 The current hypothesis is, although these contaminants are not very toxic individually, their potency appears to be increased when they are present together.On 27 April, researchers from the University of Guelph, in Ontario announced they had created crystals chemically similar to the ones found in contaminated animals by combining melamine and cyanuric acid in the laboratory under pH conditions similar to those in animal kidneys.In light of these findings, on 1 May, the American Veterinary Medical Association noted in a press release the "extremely insoluble" crystals formed in animal kidneys are suspected of blocking kidney function.