Recently I ordered a new box of SAM-e online and when it came, I was surprised to see Isopropyl Alcohol and Methylene Chloride listed as ingredients. They were not listed on the online ingredient list when I purchased them.
Isopropyl alcohol and methylene chloride are toxic, so the amount used in the supplement is small. But methylene chloride is found in some furniture strippers and has caused fatalities. (See http://www.atsdr.cdc.gov/toxprofiles/methylene_chloride_addendum.pdf). So I called the manufacturer (Natrol). Their customer service rep explained that methylene chloride and isopropyl alcohol are part of the enteric coating. They have been in the product all along but were not required to be listed until recently! So I imagine that we will be seeing a lot of these ingredients revealed on labels now that regulations require it. Obviously the amount in a single tablet is small, but people who take a variety of coated medications and supplements might be consuming more than desirable. I was not able to find a site dealing with this issue but there must be one out there. Let me know in the comments if you know of a study on the safety of methylene chloride as an ingredient.
NOTE: Although SAM-e is available without prescription in the USA, persons with bipolar conditions are advised to not take it. (See article.)