Learning Center

Phthalates and DEP in Fragrance Oils

Phthalates are a broad family of compounds, and exactly one member of it is used in fragrance: DEP. Here is what DEP does in a fragrance oil, which phthalates regulators restrict, and how to check the status of any oil we carry.

Skeletal chemical structure diagram of diethyl phthalate (DEP), labeled with its name

Phthalates have received a lot of attention over the years, yet there is still considerable confusion about what they are and how they're used. The term covers a wide variety of compounds of differing chemical structure[1]; no one would call all berries or all mushrooms unsafe because some species are toxic, and phthalates differ from one another in the same way. The safety concerns you have read about center on dibutyl phthalate (DBP) and diethyl hexyl phthalate (DEHP). None of our fragrance oils contains either. The oils we carry that are not labeled phthalate-free contain exactly one phthalate, diethyl phthalate (DEP), and more than 200 of our fragrance oils contain no phthalates at all. Every product page states which group an oil belongs to.

What Phthalates Do in Fragrance

In a fragrance oil, DEP is a workhorse solvent and fixative[2]. It dissolves fragrance components into wax and other bases, helps disparate ingredients blend evenly, and acts as a fixative that makes a scent last longer. It is particularly useful in candle fragrances because it solubilizes the fragrance into the wax and prevents crystallization in certain oils. Outside the fragrance industry, DEP is also the denaturant in SDA Alcohol 39-C, the denatured alcohol formula endorsed by the US government.

The Restricted Phthalates

Seven phthalates are classified as CMRs (carcinogenic, mutagenic, or reproductive toxicants), and the European Union barred them from cosmetics and skin care products in 2004[3]. These seven are the source of the family's bad reputation.

The Seven CMR-Class Phthalates

PhthalateCAS numberRegulatory status
DEHP (di-2-ethylhexyl phthalate)117-81-7California Prop 65 list, 1988; EU cosmetics ban, 2004
DBP (dibutyl phthalate)84-74-2Prop 65 list, 2005; EU cosmetics ban, 2004
BBP (benzyl butyl phthalate)85-68-7Prop 65 list, 2005; EU cosmetics ban, 2004
DnHP (di-n-hexyl phthalate)84-75-3Prop 65 list, 2005; EU cosmetics ban, 2004
DIDP (diisodecyl phthalate)26761-40-0Prop 65 list, 2007; EU cosmetics ban, 2004
DINP (diisononyl phthalate)28553-12-0CMR classification; EU cosmetics ban, 2004
DnOP (di-n-octyl phthalate)117-84-0CMR classification; EU cosmetics ban, 2004

Where DEP Stands

The one phthalate that is used in fragrance, DEP (CAS 84-66-2)[5], has been reviewed repeatedly by the bodies that regulate fragrance and cosmetics:

  • The International Fragrance Association (IFRA) publishes a position on DEP stating that consumers can use fragranced products containing it with confidence.
  • The European Union's SCCNFP scientific committee published a safety review of DEP on June 4, 2002, concluding that it showed low levels of toxicity and that its safety profile supports its use in cosmetic products, with no specific warnings or restrictions recommended. The committee re-asserted that opinion in 2003, and its successor, the SCCP, did so again in 2007[3].
  • The FDA, the US EPA, and the Research Institute for Fragrance Materials (RIFM) publish no restrictions or warnings on DEP in fragrance.

The testing behind those opinions found DEP to be neither a CMR nor a skin sensitizer or irritant[4]. That record is why DEP is sometimes called the "good phthalate" in the trade, and why it remains in wide use as a fragrance solvent, blender, and fixative.

Phthalate-Free Labeling

Many makers and their customers prefer to avoid phthalates altogether, and a phthalate-free label has become a selling point in candles, soap, and skincare. That preference is easy to serve: more than 200 of our fragrance oils contain no phthalates of any kind, giving you a broad selection of scents to choose from. Browse our phthalate-free fragrance oils, or check the status line on any product page.

Sources

  1. Phthalates (Environmental Factor) National Institute of Environmental Health Sciences, National Institutes of Health, 2014
  2. Phthalates in Cosmetics U.S. Food & Drug Administration, 2022
  3. Opinion on Phthalates in Cosmetic Products (SCCP/1016/06) European Commission, Scientific Committee on Consumer Products, 2007
  4. ToxFAQs for Diethyl Phthalate Agency for Toxic Substances and Disease Registry
  5. Diethyl Phthalate (Compound CID 6781) PubChem, National Center for Biotechnology Information

Frequently Asked Questions

Do candles have phthalates?

Some do. A candle's phthalate content depends on the fragrance oil used to make it. If the fragrance oil contains DEP, the finished candle will contain that phthalate as well. If the fragrance oil is phthalate-free, the candle will be too. None of the seven restricted, CMR-class phthalates is used in the fragrance industry. Every Lone Star fragrance oil product page clearly indicates whether a fragrance oil is phthalate-free.

What do phthalates do in fragrance oils?

In fragrance, DEP works as a solvent and carrier: it dissolves fragrance components into wax and other bases, helps blend them evenly, acts as a fixative that makes the scent last longer, and prevents crystallization in certain oils. It is the only phthalate used in the fragrance industry.

Is DEP one of the restricted phthalates?

No. The seven restricted phthalates (DBP, DEHP, BBP, DINP, DIDP, DnOP, and DnHP) are classified as carcinogenic, mutagenic, or reproductive toxicants and were barred from cosmetics in the EU in 2004. DEP (diethyl phthalate, CAS 84-66-2) is a different compound; the FDA, US EPA, IFRA, and RIFM publish no restrictions or warnings on its use in fragrance.

How do I know if a fragrance oil is phthalate-free?

Check the product page: every Lone Star fragrance oil lists its phthalate-free status alongside its flash point, vanillin content, and gel and soap compatibility. More than 200 of our oils are phthalate-free, and the ones that are not contain only DEP.