What Might Be Happening When You Rub Perfume Vs. Spray It? An Answer by Dr. Ryan M. Spoering of Harvard University {Ask Marie-Helene}

As a follow-up to the debate initiated by Gretchen of Beauty Hatchery on whether or not to rub perfume I thought it would be worthwhile to ask a chemist what he thought of the question. I more specifically wanted to ask what might be happening when one rubs perfume onto the skin vs. sprays it. Turning to a trusted source, I put the question to Dr. Ryan M. Spoering, a chemist at Harvard University. Here is what he had to say in response to my query....

TSS: "What would be the difference between a perfume that is sprayed onto the skin and let to air-dry versus a perfume that would be rubbed into the skin? There is a popular "theory" that rubbing would "crush the perfume molecules". I personally have empirically noted that there is or seems to be a difference in the smell when you rub in the fragrance as if the notes seemed less distinct and "crushed". It also seems like the pyramidal structure of the scent is upset by this action (a classic 3-tiered pyramid displays the most volatile notes at the top and the least volatile ones in the base or rather the pyramid is constituted by the differences in volatility of the notes).

What might be happening? Just heat provoked though friction making the notes evaporate more quickly and differently?"

Dr. Ryan Spoering: 

"Hmmm, there might be several explanations for this.  You definitely can't crush molecules or change them chemically by rubbing them.

The best explanation I can think of is that by rubbing perfume into your skin you a) hasten the absorption of substances into your skin and b) spread them out evenly into a film, making them evaporate more immediately into drafts of air.  The most volatile substances would probably be rapidly lost into the air, leaving the more oily, slow-evaporating substances.

Sprayed, undisturbed perfume would land in tiny atomized droplets which have a much lower surface area to volume ratio than a thin smeared film.  The most volatile substances would stay dissolved in the droplet longer and be released more slowly, and they would definitely be absorbed more slowly into your skin". 

 

It's up to you to decide whether this phenomenon translates into a significant difference in olfactory terms. It does to me is all I can say.

Our many thanks to Dr. Ryan Spoering for having provided an answer to this most urgent question originating from the perfumistas' community.