  There may unique ("smoking-gun") signatures of the breakdown of CPT symmetry,
induced in some models of Quantum Gravity entailing decoherence for quantum
matter. Such effects can be observed in entangled states of neutral mesons via
modifications of the respective Einstein-Podolsky-Rosen (EPR) correlators
("omega"-effect). In the talk I discuss experimental signatures and bounds of
the omega-effect in Phi- and B-factories, and argue that the effect might be
falsifiable at the next generation facilities.
