Lead is a heavy metal that is toxic to human health. Some dishes and cookware contain lead, as it is used to make the glaze and coloring for dishes and ceramic cookware. Lead is not considered safe for exposure at any level. As it can stay in the body for an extended period, levels build up over time, making even small levels of lead ingestion very dangerous. Dishes and cookware sold in the United States after the 1990s are considered safe, but watch out for older items, or ones that come from countries with less strict manufacturing laws.
The Food and Drug Administration states that a 1 microgram per milliliter leach for large cooking dishes, such as slow cookers, is considered acceptable. However, most manufacturers these days do not use lead in their color glazes. In the cases where some dishes or slow cookers contain minute traces of lead, the dishes are treated with lead-free glaze, so there is minimal chance of leaching. Tableware is not considered a major source of lead exposure.
Age and Origin
Older ceramic cookware and dishes have a greater chance of containing high levels of lead. These dishes were made before lead use in tableware was regulated. As well, in some cases, dishes may leach more lead as they age. Tableware that is manufactured overseas often does not need to meet the stringent lead safety requirements of the FDA, so there is a greater risk of lead poisoning. However, if you purchased the item in the United States, it must meet the government's strict requirements regarding lead for it to be legally sold in America.
Lead is used to create a strong, clear glaze for tableware, but it is also used in the production of bright colors for ceramic cookware. This means that you need to watch for both clear glazes — most often used to make rustic cookware — as well as bright colors. For example, terra-cotta pots either handmade in the U.S. or from Latin American countries are potentially hazardous sources of lead. Do not use for cooking, storing or serving food unless you are sure they are made with a lead-free glaze. Bright colors — such as red or yellow — on the inside of a dish are also a potential sign of lead use in ceramics.
Purchase tableware and slow cookers labeled lead-free rather than lead-safe to guarantee that your ceramics have no lead. Lead-free tableware may be especially important if you are cooking for children, as they are more susceptible to the dangers of even a trace amount of lead. White tableware, including slow cookers, rarely contains any lead-based glazing. You can also choose to use non-ceramic options, especially for slow cooker inserts. Stainless steel or glass inserts for slow cookers, and also for tableware, will not contain any lead and make for an attractive serving vessel.