Test for Lead Contamination in Ceramics (Dishes & Cookware)
Lead-containing glazes are used in the ceramic industry in pottery, earthenware, bone china, and porcelain. When the ceramic ware is fired properly (at high enough temperatures), the lead is sealed into the glaze and will not leach from the surface. However, if the glaze is incorrectly formulated OR fired improperly during the manufacture process, hazardous levels of lead may leach from the surface into the food we eat.
Dishes can also wear out over years of everyday use. Any cracks or chips should be tested and if positive for lead should not be used for food.
Acidic food such as oranges or grapefruit, tomato juice, coffee or tea, etc. can cause more lead to leach into foods than non-acidic foods like water or milk. Heating food on ceramic ware in the microwave increases the rate in which the lead leaches from the glaze.
Most Lead Crystal is 24% lead by weight and like ceramic wear, the manufacture requires a firing process. If fired properly and treated, lead will not leach from the vessel. If improperly fired and treated, it is possible for the lead to leach from the glass.
Important: In a set of dishes, the manufactures can not guarantee that all dishes were produced or fired at the same time. It is recommended to check about 10% of a set of dishes. If any items test positive, consider testing all remaining pieces before use.
Supplies
- LeadCheck® Household Lead Test Kit
- Object to be tested for lead
Steps
- Activate the LeadCheck® Swab per the directions.
- Rub across all glazes on the dish for 30 seconds.
- If an unmistakably pink color appears on the swab, and/or on the ceramic surface, lead is leaching from the piece at a hazardous level.
High Risk Items
Old China
Handed down from previous generations. Be sure to test any cracked or chipped areas. Homemade or Hand Crafted China
From U.S. or abroad. Check to see if the manufacturer uses leadfree glaze or high tempature, commercial type firing practices. Highly Decorated Multi-Colored "Inside" Surfaces
High levels of lead are typically found in brightly colored glazes. Decorations on Top of the Glaze
Can you feel the decoration when you rub your fingers on the surface? Can you see the brush strokes showing that decoration was painted on? Corroded Glaze
A dusty or chalky residue on the glaze after the piece has been washed. This is extremely dangerous and should never be used to serve food in or drink.
Don'ts
- Store food or drink in a lead containing ceramic pitcher or bowl.
- Store highly acidic foods in questionable china.
- Questionable pieces of china should not be used in your everyday routine
- Questionable pieces should not be heated in the microwave oven because the heat can accelerate the lead leaching process.
If lead is identified in your home, then use these "lead safe practices":
- Get children tested even if they appear healthy.
- Wash children's hands, bottles, pacifiers, and toys often.
- Regularly clean floors, window sills, and other surfaces.
- Replace mini-blinds that test positive.
- Avoid using positively-tested dishes on a regular basis.
- Avoid using dishes that test positive for storage or for serving acidic foods.
- Don't leave toys that may contain lead in the sun.
- Never sand lead paint.
For a guide on reducing lead exposure when renovating or remodeling, ask for "Reducing Lead Hazards When Remodeling Your Home" published by the EPA. For further assistance consult a lead professional.