Na voljo so poskusi celičnih transformacij sesalcev, s katerimi se merijo zmožnosti snovi, da povzroči morfološke in vedenjske spremembe v celičnih kulturah, ki naj bi bile povezane z malignimi transformacijami - in vivo (metoda B.21).
Mammalian cell-transformation assays are available which measure the ability of a substance to induce morphological and behavioural changes in cell cultures, which are thought to be associated with malignant transformation - in vivo, (Method B.21).