This is approximately 7 on the pH scale, which may be higher than that of shampoos which are pH adjusted for specific skin or hair effects, and lower than that of shampoo made of soap. Shampoos generally contain suites of surfactants that act synergistically—each has its own role, but they also work in concert to improve the overall formulation. Polyethoxylated surfactants play a number of roles in a shampoo system. For example, sodium laurylglucoside promotes mild cleansing, whereas hydroxypropylsulfonate provides smoothing and soothing properties to the formulation.
Alkanolamides a category of surfactants —and an example of one you might see listed on a label is cocamide MEA— another type of gentle nonionic surfactant that provides foam stabilization and viscosity-building properties.
These alkyl ingredients actually can temporarily numb the eye and worse. They are used in pesticide products to anesthetize insects and they can penetrate the skin and cause organ toxicity in people. So when you see these ingredients listed on the label, you know that the shampoo is an acidic, lower pH formula with inexpensive, harsh, eye burning, stinging ingredients. Your eyes are fine. Your fragile sense of self and your childhood reading capabilities is fine. Your age should not determine whether or not you should squirt shampoo in your eye.
And if that tear-free claim did, in fact, lead you to do so, well — if you could read about it in the first place, you were probably old enough to have known better. Which makes scary sense, except for the fact that it's false. Baby shampoos don't contain anesthetics. If they did, your hands would feel number after washing baby's hair. And babies and children using the products would be at risk for overdose as they absorbed chemicals through the skin or accidentally ingested them as bubbles or bath water.
Lidocaine, for example, is particularly toxic to little bodies [source: del Rey ]. If a "no tear shampoo" doesn't contain anesthetics as urban legend suggests , then why doesn't it sting sensitive orbs? The answer lies in a few subtle changes in chemical formulas. Adult and baby shampoos contain surfactants short for "surface active agents". One end of the surfactant molecule is attracted to water. The other is repelled by water but attracted to oily substances.
Surfactants work by reducing the surface tension of a liquid, allowing the shampoo to spread and penetrate better, and remove the thin layer of oil known as sebum from the hair and scalp [source: Schwarcz ]. Baby shampoos use detergents with long chain surfactants, such as sodium trideceth sulfate or nonionic polymers that are less harsh than normal detergents, and they use only small amounts of these cleansers in their shampoos. Tear-free formulas also leave out surfactants such sodium lauryl sulfate , which can be irritating to the eyes and scalp.
This does create a trade-off, though. Sodium lauryl sulfates -- formed in part from coconut fat or palm kernel oil -- are the chemical agents in shampoos that get hair really clean and give a nice lather [source: Schwarcz ].
Although tear-free shampoos still clean hair, they don't remove oil as thoroughly. But since most babies don't do more than look cute and occasionally smear food into their hair, this usually works out just fine.
If you have children, you are probably aware of tearless shampoos for babies. You may have wondered if the same type of product is available for your four-legged family members as well.
Thankfully, the answer is yes. Tearless shampoos for pets serve the same purpose that tearless shampoos for babies do. This becomes especially important when you are bathing a pet that gets rambunctious in the tub! You may be wondering if you can just use the same tearless shampoo for your pet that you do on your baby.
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