Some hard facts
Michael Dresdner
>Addy Protocol: Because of a caffeine problem some years ago, I did a good bit of research into decaffeination. Because my field is coatings, including paint removers, I have also heavily researched DCM (Methylene chloride is the common name for di-chloro methane, or DCM).
Most decaf contains only one fortieth of the caffeine, or just over two percent, not, as someone said, 'much of the caffeine remains.'
I would not hesitate to drink coffee decaffeinated with DCM. For one thing, it tastes better. Water process robs the coffee of some taste. As was pointed out, DCM is an excellent solvent for caffeine, but does not touch many of the other flavor bearing elements that are water soluble.
Again as someone else pointed out, DCM evaporates at room temperature, boils off well below 200 F, and is completely obliterated during roasting, which takes place AFTER decaffeination at temperatures well above that.
There is also the matter of DCM itself being labeled as a carcinogen. In fact, it has been labeled, I believe incorrectly, as a suspected carcinogen. Suspected is a very different thing than actual.
In extensive tests it has been shown to be not a carcinogen at all. In one notable ten year tracking at a plant that exposed its workers to much higher levels than we get, the cancer level in the work force was actually lower than the control group, the unexposed public at large. In addition, I have never been able to find even a single case of cancer definitively linked to DCM, the main reason it is still only a suspected one.
I would guess that the primary reason it is 'suspected' is that its structure is rather similar to a different known carcinogen, carbon tetra chloride. However, as we all know, small differences can yield big results.
As for the ozone issue, DCM was de-listed as a VOC several years ago after it was proved that it is not an ozone generator, the primary qualification for a VOC.
The bottom line is that coffee decaffeinated with DCM is about as safe as regular coffee. Whether you feel coffee is safe to drink is up to you. Personally, I love the stuff, but then I live near Seattle where love of coffee is mandated by law.
Incidentally, after several years I decided I would rather drink much smaller amounts of regular coffee, and I no longer drink decaf.