The reliability of aqueous analysis by the atomic absorption spectrophotometer for copper ion content in samples from eyes containing intravitreal pure copper particles was investigated. It was demonstrated that values of copper ions rose well above the normal in the aqueous as well as in the vitreous of such eyes. The standard deviations of the mean values were generally high. It was also found that a similar copper ion content increase occurred in eyes containing iron particles. The possible clinical implications of these findings are discussed.