Blog

Will you please grab the mayo from the fridge? It’s next to the shampoo.

Applications Scientist , LANXESS
October 13, 2021

By Stephen Foster, Jenna Blankenship, Rosanna Stokes

Running after work has always cleared Paul’s mind. After a run, he looks forward to a post-workout shower followed by a quick meal. He grabs turkey and mayo from the fridge and makes his favorite sandwich. Before he can finish, his daughter pulls him away for a tea party-related crisis. The next morning, the mayo and turkey are still sitting out on the counter. Oops! Into the trash they go...

Microbes love food just as much as we do. They thrive on the mixture of water, proteins, fats, oils, carbohydrates, turning them into energy, like humans. Refrigeration allows us to store unpreserved foods at temperatures that keep microbes from growing quickly. Mayo and turkey, for instance, provide an ideal environment for them to grow. What else contains all the components microbes need to thrive? Shampoo.

We don’t think about it as much, but cosmetics and personal care products – including shampoo, lotion, aftershave, makeup, etc. – also need to be properly preserved. Especially when you factor in germy fingers dunking into a jar over and over, re-using containers and pumps, or storing products in warm, moist environments like your bathroom. As product formulators, we counter microbial growth with preservatives because, if we didn’t, your shampoo would need to be stored in the fridge, on the second shelf, right next to the mayonnaise. Suddenly, your hot shower with cold shampoo from the fridge – or worse, mistaken mayo – doesn’t seem quite as relaxing.

You may have heard or read about problems with cosmetic preservatives in the news or on social media, but what you’re seeing likely isn’t backed by decades of scientific research. Harmful microbes can and will grow in personal care items that aren’t properly preserved, creating pungent odors, unappealing mold and even potential health hazards. If preservatives were removed from cosmetics and personal care products, what would happen?

Shelf life, storage and packaging protocols would immediately have to change. Products would have much shorter expiration dates and packaging might move to a one-shot use (think single-serving ketchup packets), which would lead to increased costs and waste generated by each use. Bottled products would have to be stored in the fridge when not in use. Even then, some microbes would still grow (including fungi and spoilage bacteria – yuck!), and some products may need to be disposed of much sooner than most people could use them, which would be incredibly wasteful.

Fortunately, we have a range of preservatives available, all of which are demonstrated to be safe when used in personal care and cosmetics products. Preservatives do a wonderful job at keeping us safe and reducing waste, energy usage and prices at checkout.

And hey, that’s one less thing to forget and leave out on the counter!