You might be surprised to learn that lead is the active ingredient that creates the elaborate fractal patterns in crystal goblets and many other crystal drinking glasses.
According to Gurasu Fine Crystal, any glass that contains between 10% and 24% should be labeled as crystal glass. The more lead a glass contains, the more brilliant its sparkle.
Like other heavy metals, lead does not biodegrade or disappear from an environment over time, so the lead in crystal glasses sticks around, starting from the day they're made.
Lead crystalware can indeed release lead into the beverages. Any exterior decorative pattern around the rim, such as a coating or glaze, may also release lead.
Lead poisoning primarily impacts the brain and nervous system. It can cause serious neurological issues and can even lead to the development of learning disabilities in children.
However, drinking from a lead crystal glass on occasion won't poison you. You just have to use them sparingly, which won't be hard since crystal glasses are often family heirlooms.
Use these glasses in moderation and drink quickly to minimize the time the beverage spends in contact with the glass. Never use crystal decanters to store alcohol long-term.
If you're feeling nervous about your crystal glass set, you can always grab a lead test kit. The EPA recommends the brands 3M LeadCheck and the D-Lead.