Saline implants removed, and I asked to keep them. What could these particles inside the implant be? (Photo)

I had my saline smooth implants removed, and I got implants back after the surgery. PS said they did not rupture. In one implant, there are brown flecks and brown small solid particles inside the saline implant, all floating around. Implant does not appear to have leaked. What could these particles be? Thank you for your help!