by multiple factors, and aluminum is just one of them. Still, this factor is easily avoided. All it takes
is a small change in consumer habits.
Propylene Glycol: Beauty Dissolved
Do you know what baby wipes and aircraft deicing fluid have in common? Both have glycols as a
main ingredient. Members of this family of multitasking chemicals are used in many cosmetic
products, including baby washes, bubble baths, deodorants, shampoos, hair dyes, and personal
lubricants (where propylene glycol works to deice the passion, most likely). All members of the
glycol family are easily biodegradable and do not accumulate in soil or water, which is the only good
thing about them.
There has been a lot of confusion between propylene glycol (PG), diethylene glycol, ethylene
glycol, and polyethylene glycol (PEG). While all of them have similar-sounding names, these
chemicals have different safety ratings. Propylene glycol is a popular humectant (an ingredient that
helps draw moisture from the air to the skin) and a penetration enhancer used in many cosmetic
products. It helps products such as stick deodorants retain their solid form and prevents melting. The
FDA considers propylene glycol to be “generally recognized as safe” for use in food, cosmetics, and
medicines. However, it banned this chemical from cat food in 2001.
Ethylene glycol is considered less safe. Apart from its use in antifreezes and deicing fluids,
ethylene glycol is found in photographic developing solutions, hydraulic brake fluids, and in inks used
in stamp pads, ballpoint pens, and print shops. There is a higher dose of ethylene glycols in children’s
shampoos and baby washes, to make them “less irritating” to a baby’s whisper-thin skin.
Diethylene glycol is toxic to humans and animals. It is not allowed for food and drug use but can be
found in polyethylene glycol in very low concentrations.
Polyethylene glycol (PEG) is another popular cosmetic ingredient. It’s frequently used in “natural”
cosmetics as well as in laxatives and other medications that have to be delivered in a slippery, syrupy
form. PEG, just as propylene glycol, is also used as a food preservative. It is considered generally
safe to use by cosmetic manufacturers “with a maximum concentration of use of 20 percent,” with a
warning: “On damaged skin, cases of systemic toxicity and contact dermatitis in burn patients were
attributed to a PEG-based topical ointment” (CIR Expert Panel 2006).
what
science
says
When it comes to short-term effects from daily use, contact allergic dermatitis is the most common
side effect of using products containing propylene glycol and various PEGs. These chemicals are
known to aggravate acne and eczema by rupturing skin cell membranes (Gonzalo et al. 1999).
Propylene glycol, used as a penetration enhancer and humectant, has been found to provoke skin
irritation and sensitization in humans in concentrations as low as 2 percent, while the industry review
panel recommends that cosmetics can contain up to 50 percent of the substance (Johnson 2001).
Current studies have not shown that propylene or the other glycols can cause cancer when used in