A high copper level in water used for processing medical devices can cause various issues. Aesthetic issues include bluish-green, grayish-green, or dull gray appearance of stainless steel surgical instruments, washer chamber walls, steam sterilizers, plastic utensils, etc. Copper salt deposits can encourage galvanic corrosion, reduce the useful life of surgical instruments, transfer residues from instruments onto tray liners, and cause staining of trays during steam sterilization. Steam generator feedwater with elevated copper content can cause deposits to form and result in shortened service life of the generator heating elements and allow for carry-over of copper ions during steam sterilization.
Water and stained surgical instrument samples, containers and tray liners were received from Customer sites via the STERIS Diagnostic Solutions Service (DSS) Program for evaluation and troubleshooting purposes. Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) was used for evaluating water and residue samples. The water samples were analyzed “as is”, while the instruments with stains were evaluated by using swab extraction methods. Evaluation showed correlation between water samples containing elevated copper levels and residue results for the stained instruments. These issues can be mitigated with routine monitoring of water used for processing medical devices.