D4 is a residue, an impurity that is not on the ingredient list. However, there may be trace amounts of residues in skin care products, shampoos, conditioners, and makeup products, and the amount of D4 residues in different silicone oils (organic silicones) varies. However, it is not clear whether trace amounts of residues will cause health problems to the human body. But the less the better, just like the dioxane in SLES.
For D5, do you see if it says “cyclopentasiloxane” on the ingredient list? If so, that’s it. See if they are all at the front of the ingredient list? Yes, this product is often added in large amounts by formulators.
