When McDonald's recalled its promotional "
Shrek Forever After" glasses because of cadmium risks two questions loomed: How much cadmium was in the glasses, and how dangerous was it for kids to handle them?
Scott Wolfson, a spokesman for the
Consumer Product Safety Commission which announced the recall, said the glasses are non-toxic.
McDonald's said that "in light of the CPSC's evolving assessment of standards for cadmium in consumer products," the company decided that a recall was appropriate. So we decided to test a few glasses to assess the risk.
There are four different glasses in the set—the two we tested were the Shrek and Puss n' Boots versions. We first screened the glasses using an XRF (X -Ray fluorescence) gun, a non-destructive analytical instrument used for detecting heavy metals such as lead and cadmium. The XRF results indicated the presence of cadmium in the cartoon decals on the outside of the glass. But since XRF is only a screening tool, we did additional analytical testing at an outside lab to get a more precise measure of the amount of heavy metals on the glasses.
To assess the total amount of cadmium, the lab attempted to scrape the paint off the glasses, but found that to be difficult, indicating that it may have been bonded to the glass. The lab had to file the paint off the glass to gather enough sample for analysis. Using an emission spectrometer, the lab was able to detect high levels of cadmium—as much as 23,000 parts per million. By comparison, the federal limit on lead in paint is only 90 parts per million.
Because the cadmium-laden paint was so difficult to remove from the glass, we wondered if it could come off on a child's hands. To determine that, we used another industry-standard test in which a special cloth is wiped over the painted surface in a prescribed manner to see if any cadmium transferred to the cloth. Sure enough, it did.
We analyzed the amount of cadmium that transferred to the cloth and made some assumptions as to how much could be transferred from the glass to a child's hands and then from the hands to the mouth (while eating, for example). Our analysis indicated that these glasses pose a low but unnecessary risk. There may be no safe level of cadmium and, like lead, exposure to it should be avoided. We know that cadmium can lead to kidney disease and accumulates in the body over time. Manufacturers should take whatever measures possible to eliminate accessible cadmium from their products.
As noted, our assessment is based on testing just two of the four glasses in the set. We also haven't determined what happens to the cadmium when the glasses are put through multiple dishwasher cycles and worry that that might make the cadmium more accessible. (Painted decals tend to wear away in the dishwasher.)
We applaud McDonald's for reacting so quickly to recall these glasses once the hazard was identified. We also like the fact that the company is offering affected consumers
a bounty—$3.00 to return glasses they bought for $1.99 or $2.49. The premium gives consumers an extra incentive to get the glasses out of their homes.
—Don Mays
