Farak does not have a listed phone number, and it was unclear whether she had a lawyer.
The Amherst lab has been closed temporarily, and chemists will be transferred to Sudbury, state police said.
The state's district attorneys said they were undertaking internal case reviews to determine which, if any, of their prosecutions involved Farak.
The Massachusetts District Attorneys Association said Sunday prosecutors remain committed to ensuring the rights of defendants are respected and will remain proactive in identifying possibly compromised cases and notifying defense attorneys.
The association said the fallout from the Dookhan case includes experienced prosecutors being taken out of rotation to serve on Department of Public Health task forces. It urged lawmakers to give prosecutors the resources they need to ensure "proper functioning" of the state's criminal justice system.
Farak is due to be arraigned Tuesday in Eastern Hampshire District Court in Belchertown.