What is Decamethylcyclopentasiloxane (D5)?

What is Decamethylcyclopentasiloxane (D5)?
Decamethylcyclopentasiloxane Chemical Compound

What is Decamethylcyclopentasiloxane (D5)?

Decamethylcyclopentasiloxane (aka D5) is a colorless and odorless liquid used as a chemical intermediate in the production of polydimethylsiloxane silicone polymers. What does any of that actually mean, you may ask? Well, in simpler terms D5 is a chemical produced in a reaction – like many other chemicals – that is then used for the formulation of many personal care products. 

Want a hot take? D5 may have been classified as “non-toxic”, but it is still a carcinogen (cancer causing agent) and can impact the nervous system, fat tissue, the liver, immune systems, and, if lit on fire, results in the formation of formaldehyde.

What kind of products are made with D5?

D5 is largely used as a solvent in industrial cleaning fluids, as it is a chemical that breaks down stains very easily. D5 is also used in blending and forming personal care products, including shampoo, skin cream, and deodorant. It is also used as a solvent for dry cleaning to dissolve stains. Wait.. there are liquids involved in dry cleaning? Why is it called “dry” cleaning then? Here is a link to our blog that talks about what dry cleaning actually is!

Is D5 “good”?

Initially, it was concluded that D5 should be added to the toxic substances list of the Canadian Environmental Protection Act in 1999. However, because of its prominence in many personal care products and in the dry cleaning business, many industries opposed this addition and a three-person board of review was established to re-evaluate the risk assessment. Ultimately, that three-person council decided that D5 “does not pose a danger to the environment”. It is unclear whether there were any ulterior motives for this council of three people, but what is known about D5 would lead most to believe that it is, in fact, toxic because it poses significant dangers to human health and the environment. 

Are there certifications I should look out for?

Unfortunately, not. Even GreenEarth, the largest “environmentally friendly” dry cleaning technology provider, uses D5 in its dry cleaning solvent. Be aware, there is nothing “green” about this method of cleaning. Companies will try to hide this harmful chemical by using the name GreenEarth, so try to avoid it. 

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