2006 Starbucks Coffee Brand Ceramic Mug with Pear and Flower Design:
Positive for lead (Pb) with levels as high as 304 ppm lead (+/- 37 ppm) when tested with an XRF instrument. This mug was negative for cadmium, arsenic and mercury.
The amount of lead that is considered toxic in the substrate of an item manufactured today as intended for use by children is anything 100 ppm lead or higher. (90 ppm or higher in the glaze.) Dishes and glassware are not generally regulated for lead levels as detectable with an XRF because they are not considered to be “items intended for use by children.”