Many accelerators of electron beams are susceptible to persistent beam lifetime disruptions, with correspondingly reduced performance. One distinguishes between three prevailing explanations of these disruptions: (1) trapping of positive atomic ions in the negatively charged beam; (2) trapping of small highly positively ionised micro-objects ("dust") in the negatively charged beam; (3) disruptions due to stray magnetic objects trapped in the magnetic field of undulators.The lifetime disruption of certain electron storage rings that employ ion-getter pump systems are attributed by most researchers to explanation (2), the trapped dust hypothesis. Systematic experimental studies of HERA, PETRA and DORIS reinforce the suspicion that specifically this type of pump system is the culprit.Examples of beam lifetime disruptions are presented, together with a summary of observations and experiments performed at various afflicted storage rings to investigate dust trapping and the connection between ion getter pumps and dust particle release. Observations of the disrupted beam are found to agree with the dust trapping hypothesis. . The complementary experience at these machines has built a consistent picture of the symptoms of macroparticle lifetime disruptions, and this picture agrees quantitatively with the dust trapping model detailed in [3,4].This electron beam lifetime problem is beam charge dependent, i.e. it only occurs with electron beams, as evidenced by the problem-free switch to positron operation in HERA and DORIS.Observations confirm that the ion getter pumps of all above-mentioned machines are implicated in casting dust particles into the beam pipe. The lifetime disruption can be provoked by switching an ion getter pump on and off, or by abruptly increasing the pump voltage, when a discharge within the pump can be sometimes be observed.Such lifetime disruptions are not observed in the nonevaporative getter (NEG) pump based storage ring LEP or at ESRF (with NEG pumps and auxilliary lumped ion pumps), with the exception of the possible capture of magnetic dust in undulators [7]. Trials over a limited region of HERA with NEG pumps indicate a strong if not complete reduction of the release of disrupting particles within this NEG pump region.It will be illustrated in this report that the extensive observations of beam lifetime disruptions in a number of accelerators are well described by the trapped dust hypothesis. However, the formation or liberation of dust particles within the complicated environment of the ion-getter pump chamber is poorly understood. Relatively few direct observations of the processes within these pumps systems are available, whereas many observations of pump configurations and operating conditions conducive to the onset of beam lifetime disruptions have been performed, in particular with HERA, PETRA and DORIS. Such observations are however not sufficient to form a causal model of dust particle release into the beam pipe; our knowledge of the processes on the pump side of the vacuum ch...

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