Exchanging one poison for another

Many products claim to be free of one thing or another, in turn being better for you or the environment. I think this is a marketing gimmick, because on inspection they are replaced with something else, usually newer, less tested and so with less known about them.

My first example is MSG. It causes thirst and headaches in some people. I saw a brand of instant noodles claiming to be MSG free. This does not mean it is replaced by some natural ingredient, instead the noodles contains some chemical I didn't recognise, so I stuck to the tried and tested MSG.

The other example is acetone free nail polish remover. People know acetone is bad for them, so a nail polish remover without acetone must be better, right? Maybe you'd prefer MEK, almost identical to acetone, gamma butyrolactone http://www.ncbi.nlm.nih.gov/pubmed/16035208 or good old highly toxic methanol?

Other examples I could think of:

• BFRs
• Bisphenol-A
• Dioxins
• CFCs

Very often, the replacement isn't safer, it's just that we don't know how dangerous it is yet. I believe some replacements will be found to be worse than the original in the future.