I seem to have missed this NYT article over last weekend. Following from the continuing appearance of diethylene glycol in glycerin imported from China, yet another consumer product is found to be adulterated, again in Panama:
Diethylene glycol, a poisonous ingredient in some antifreeze, has been found in 6,000 tubes of toothpaste in Panama, and customs officials there said yesterday that the product appeared to have originated in China.
This just goes to show that any product containing glycerin, from cough syrup to toothpaste, runs the risk of containing the cheap substitute, diethylene glycol.