PEG-40 Castor Oil
Mon, August 3, 2009 at 12:01 PM
[Stephanie Greenwood]

Today's Chemical:
PEG-40 Castor Oil


EWG Risk Score:
6-8 (depending on useage)

What is it?
PEG-40 is a derivative of castor oil that's used as a cleansing agent.

Why is it a risk?
According to the Cosmetics Ingredients Review PEG-40 Castor Oil "can instigate immune system response that can include itching, burning, scaling, hives, and blistering of skin." They also state it may "contain harmful impurities" like known carcinogens Ethylene Oxide and 1,4-Dioxane.

What type of products is it found in?
Moisturizers, conditioners, sunscreens, shampoos, facial cleansers.

Companies that use this chemical:

Steph's Opinion:
Sounds natural enough with "castor oil" in it's name, this ingredient is anything but natural. PEG stands for polyethylene glycol. To create PEG-40, you combine castor oil with 40 moles (chemical measurement) of ethylene oxide. Ethylene oxide is a known carcinogen, traces of which are most likely contained in the final PEG product. There are many PEGs with different numbers following them (PEG-200, PEG-20, etc) but I chose to highlight PEG-40 today because of its wide useage. In over 100 products, it's even contained in supposedly "natural" products. Watch out for any PEG, as they all have the same contamination concerns. 

Article originally appeared on Chemical of the Day (
See website for complete article licensing information.