FlavScents AInsights Entry for Diethyl Phthalate (CAS: 84-66-2)

1. Identity & Chemical Information

• Common Name(s): Diethyl Phthalate
• IUPAC Name: Diethyl benzene-1,2-dicarboxylate
• CAS Number: 84-66-2
• FEMA Number: Not applicable
• Other Identifiers: FL number not applicable, CoE number not applicable, IFRA reference not applicable
• Molecular Formula: C12H14O4
• Molecular Weight: 222.24 g/mol

Diethyl phthalate is an ester of phthalic acid and is characterized by its aromatic ester functional group. This structure contributes to its utility in various applications, particularly in fragrance formulations where it acts as a solvent and fixative, enhancing the longevity and diffusion of other fragrance components.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Diethyl phthalate itself is not typically noted for a distinct odor or flavor profile, as it is primarily used as a solvent in fragrance applications rather than as a direct sensory agent. Its role is more functional, providing a medium for other aromatic compounds to express their sensory characteristics effectively. The compound is generally considered odorless or has a very faint, sweet odor at high concentrations.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Diethyl phthalate is a synthetic compound and does not occur naturally. It is produced industrially through the esterification of phthalic anhydride with ethanol. This synthetic origin means it does not qualify for "natural flavor" or "natural fragrance" designations, which are typically reserved for compounds derived directly from natural sources without chemical modification.

Citation hooks: FlavScents; food chemistry literature; EFSA/JECFA monographs

4. Use in Flavors

Diethyl phthalate is not commonly used in flavor applications due to its synthetic nature and lack of flavor characteristics. When used, it serves as a solvent or carrier for other flavor compounds, particularly in complex formulations where stability and solubility are critical. Typical use levels in flavor systems are not well-documented, as its primary role is non-flavoring.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

Diethyl phthalate is widely used in the fragrance industry as a solvent and fixative. It is compatible with a wide range of fragrance families and product types, including perfumes, lotions, and deodorants. Its volatility is low, contributing to its role as a base note that helps stabilize more volatile top and middle notes. Typical concentration ranges vary but are generally between 1-5% in finished products, depending on the formulation requirements.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

6. Regulatory Status (Regional Overview)

• United States: Diethyl phthalate is not listed as a FEMA GRAS substance for flavor use but is permitted in fragrances.
• European Union: Not specifically listed under Reg. (EC) No 1334/2008 for flavor use; used in fragrances under general safety regulations.
• United Kingdom: Follows EU regulations post-Brexit with no significant divergence noted.
• Asia: Usage regulations vary; generally permitted in fragrances with adherence to safety guidelines.
• Latin America: Similar to the US and EU, with specific country regulations applicable.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

• Oral Exposure: Not typically relevant due to its primary use in non-flavor applications.
• Dermal Exposure: Generally considered safe in fragrance applications, though some reports suggest potential for mild irritation or sensitization in sensitive individuals. IFRA provides guidelines for safe use concentrations.
• Inhalation Exposure: Low volatility reduces inhalation risk, but occupational exposure should be managed with appropriate ventilation.

Overall, diethyl phthalate is considered safe for use in fragrances under current regulatory guidelines, with a low risk profile when used as intended.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Diethyl phthalate is valued for its ability to dissolve a wide range of fragrance ingredients, enhancing the overall stability and longevity of the fragrance. It synergizes well with both natural and synthetic aromatic compounds. Formulators should be cautious of overuse, which can lead to regulatory scrutiny and potential consumer sensitivity issues. It is often under-utilized in formulations seeking to balance cost and performance.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on diethyl phthalate is well-established, particularly in its role as a fragrance solvent. While its use in flavors is limited, industry practices are consistent with regulatory guidelines. Some data gaps exist in specific regional regulations, but these are generally harmonized across major markets.

Citation hooks: FlavScents

QA Check

• All required sections 1-9 are present
• "Citation hooks:" line is present under each section
• Flavor section includes ppm ranges where applicable
• Toxicology section covers oral, dermal, inhalation
• Regulatory section mentions US, EU, UK, Asia, Latin America
• Section 5a is not applicable as diethyl phthalate is not a complex natural material

About FlavScents AInsights (Disclosure)
FlavScents AInsights integrates information from authoritative government, scientific, academic, and industry sources to provide applied, exposure-aware insight into flavor and fragrance materials. Data are drawn from regulatory bodies, expert safety panels, peer-reviewed literature, public chemical databases, and long-standing professional practice within the flavor and fragrance community. Where explicit published values exist, they are reported directly; where gaps remain, AInsights reflects widely accepted industry-typical practice derived from convergent sensory behavior, historical commercial use, regulatory non-objection, and expert consensus. All such information is clearly labeled to distinguish documented data from professional guidance or informed estimation, with the goal of offering transparent, practical, and scientifically responsible context for researchers, formulators, and regulatory specialists. This section is generated using advanced computational language modeling to synthesize and structure information from established scientific and regulatory knowledge bases, with the intent of supporting—not replacing—expert review and judgment.

Generated 2026-06-16 09:33:24 GMT (p2)