Positive identification of silicone in human mammary capsular tissue.

A specific quantitative assay was developed to determine silicone concentrations in contracted mammary capsular tissue. The concentrations of silicone in tissues from 14 patients with gel-filled implants varied from 15 to 9800 micrograms polydimethylsiloxane per gram of tissue. This silicone is probably a high-molecular-weight polymer that has diffused through the implant envelope. Samples from a patient with saline-filled implants contained no silicone. The concentration of silicone was not related to capsule age. The polymer in these tissues appeared to be unaltered, in that no evidence of metabolic products was found.