Prior to beginning an acting career, Eads worked as a copy machine salesman, as well as selling first aid and safety supplies for Cintas.
His absence, sources say, is not considered an attempt to renegotiate his contract.
Eads -- and co-star Jorja Fox -- were both briefly fired from in 2004 after a short-lived salary standoff with the network and studio.
Speaking to The Hollywood Reporter, Mendelsohn stated, "It's been a long and amazing journey, and I am so proud of CSI's continued success.
In handing over the helm to my dear friend and partner, Don Mc Gill, I know he and our CSI team will carry on brilliantly what we've all created together.
In 2000, Eads became one of the lead characters of the CBS police drama CSI: Crime Scene Investigation, in which he portrays a Las Vegas forensic scientist named Nick Stokes.