The leaching of nickel from new and used metal spectacle frames
1Department of Vision Sciences, Glasgow Caledonian University.
Abstract:
Fifty "used" and 373 new spectacle frames were tested for evidence of nickel release using dimethylglyoxime and ammonia. Nearly all the "used" frames (96%) tested positive. A lower proportion (24.5%) of new frames showed evidence of nickel leaching. It is suggested that this is evidence of non-conformance with the current British Standard although all our suppliers believed that their frames conformed with BS 6625 (1985).
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