Capsules
Most wine bottles are sealed with a cork, although screwcaps are increasingly found. Commercial corked wine bottles typically have a protective sleeve called a capsule (commonly referred to as a "foil") covering the top of the bottle. The purpose of which is to protect the cork from being gnawed away by rodents or infested with the cork weevil., and to serve as collar to catch small drips when pouring. The capsule also serves as a decorative element of the bottle's label. Capsules were historically made of lead; However, because of research showing that trace amounts of toxic lead could remain on the lip of the bottle and mix with the poured wine, lead capsules (lead foil bottleneck wrappings) were slowly phased out, and by the 1990s, most capsules were made of tin, heat-shrink plastic (polyethylene or PVC), or aluminium or polylaminate aluminium. Sealing wax is sometimes used, or the capsule can be omitted entirely. In the US, the FDA officially banned lead foil capsules on domestic and imported wine bottles as of 1996.
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