Recent product recalls in the pharmaceutical industry over the detection of visible glass flakes (delamination) in parenteral (injectable) products has focused a great deal of attention on glass/product interactions. Because the presence of flakes is often detected after the product has been released to the market, delamination events can result in product recalls and product shortages. If one examines the glass science literature, one learns that the generation of flakes from glass surfaces exposed to water-containing environments (known as weathering) is not a new phenomenon, and in fact, the first mention of glass/water interaction was reported in 1770. This paper will look at the mechanism behind the weathering of glass, and describe specific tests that can predict glass/product interactions for glass pharmaceutical containers.
