Both acetone and non-acetone polish removers are solvents. The solvent acetone is never present in nail polish; non-acetone polish removers use solvents that are found in nail polish, usually a combination of solvents including butyl acetate and ethyl acetate.
As far as which is preferred, it’s your personal preference. Acetone is stronger and takes polish off more easily, but it dries out the nails. So, if you use acetone it’s advisable to then use a cream or oil to replace the moisture. Acetone polish removers are preferred when prepping natural nails, since you want the natural oils removed at this stage of a manicure.
Non-acetone removers have an oily feel to them. They don’t dry out the nails as much.
There’s also the issue of if one solvent is more harmful than another, but in my experience, both have such small concentrations and are used in such small amounts that no substantial harm is caused by either. — Faina Ritz is vice president of Duri Cosmetics.