FlavScents AInsights Entry: Tea Tree Oil (CAS: 68647-73-4)

1. Identity & Chemical Information

Tea tree oil, also known as melaleuca oil, is a natural essential oil derived from the leaves of the Melaleuca alternifolia plant. It is a complex mixture of over 100 components, primarily terpenes. The CAS number for tea tree oil is 68647-73-4. It does not have a specific IUPAC name as it is not a single compound. Tea tree oil is recognized by the FEMA number 3902. Other identifiers include its FL number 2830 and its IFRA reference, which provides guidelines for its safe use in fragrances. The composition of tea tree oil can vary significantly depending on the geographical origin, harvest time, and processing methods.

Citation hooks: FlavScents; PubChem; FEMA

2. Sensory Profile

Tea tree oil is characterized by a fresh, camphoraceous odor with a slightly medicinal and woody undertone. Its intensity is moderate to strong, and it is often used as an impact note in formulations. The oil's diffusion is relatively high, making it noticeable even in small concentrations. While specific taste and odor thresholds are not well-documented, tea tree oil is primarily used for its olfactory properties rather than flavor. It serves as a modifier and impact note in fragrance compositions, providing a clean and refreshing scent.

Citation hooks: FlavScents; peer-reviewed sensory literature

3. Natural Occurrence & Formation

Tea tree oil is naturally sourced from the leaves of the Melaleuca alternifolia, a plant native to Australia. The oil is obtained through steam distillation of the leaves. It is considered a natural fragrance and flavor material, often labeled as such in products. The formation of its characteristic components involves the biosynthesis of terpenes within the plant, which are then extracted during the distillation process. This natural origin and extraction method contribute to its designation as a natural flavor and fragrance.

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

4. Use in Flavors

Tea tree oil is not commonly used in flavor applications due to its strong medicinal and camphoraceous notes, which can be overpowering. However, it may be used in very low concentrations as a flavor modifier in certain niche products where its unique profile is desired. Typical use levels in finished food or beverages are not well-documented, but industry practice suggests levels below 1 ppm to avoid overpowering other flavors. Tea tree oil is relatively stable under normal conditions but can degrade with prolonged exposure to heat and light.

Citation hooks: FlavScents; FEMA GRAS documentation; formulation literature

5. Use in Fragrances

In the fragrance industry, tea tree oil is valued for its fresh, clean scent and is used in various product types, including personal care products, household cleaners, and aromatherapy blends. It is commonly found in the herbal and medicinal fragrance families. Tea tree oil acts as a top note due to its volatility, providing an initial burst of freshness. Typical concentration ranges in fragrances vary from trace amounts to around 1-2%, depending on the desired intensity and product type.

Citation hooks: FlavScents; IFRA; fragrance chemistry texts

5a. Key Constituents (Typical)

Tea tree oil's composition includes major constituents such as terpinen-4-ol, which is often the most abundant, along with γ-terpinene, α-terpinene, and 1,8-cineole. The presence and concentration of these constituents can vary based on factors like origin and processing. Terpinen-4-ol is primarily responsible for the oil's antimicrobial properties and contributes significantly to its overall scent profile.

Citation hooks: FlavScents; peer-reviewed literature; authoritative industry references

6. Regulatory Status (Regional Overview)

In the United States, tea tree oil is generally recognized as safe (GRAS) for use in fragrances but not explicitly approved for flavor use by the FDA. In the European Union, it is regulated under Reg. (EC) No 1334/2008 and has an assigned FL number, indicating its use in flavorings is subject to specific conditions. The United Kingdom follows similar regulations post-Brexit. In Asia, regulatory status varies, with Japan and China having specific guidelines for its use in cosmetics and fragrances. In Latin America, countries like Brazil recognize its use in personal care products, but specific flavor regulations are less defined.

Citation hooks: FEMA; EFSA; national authority publications

7. Toxicology, Safety & Exposure Considerations

Tea tree oil's safety profile varies with exposure route. For oral exposure, it is not typically used in flavors due to potential toxicity at higher doses. Dermal exposure is more common, with tea tree oil being a known skin irritant and sensitizer at higher concentrations, leading to IFRA guidelines on its use in fragrances. Inhalation exposure is generally considered safe in typical fragrance applications, but occupational exposure should be monitored to prevent respiratory irritation. The risk profiles differ significantly between food and fragrance applications, with more stringent controls in place for dermal and inhalation routes.

Citation hooks: EFSA; FEMA; PubChem; toxicology literature

8. Practical Insights for Formulators

Tea tree oil is valued for its antimicrobial properties and fresh scent, making it a popular choice in personal care and cleaning products. It synergizes well with other herbal and citrus notes, enhancing the overall freshness of a formulation. Common pitfalls include overuse, leading to an overpowering medicinal scent, and instability in formulations exposed to light and heat. It is frequently under-used in formulations where its antimicrobial benefits could be leveraged more effectively.

Citation hooks: FlavScents; industry practice

9. Confidence & Data Quality Notes

The data on tea tree oil is well-established in terms of its sensory profile and key constituents. However, there are gaps in specific flavor use levels and comprehensive toxicological data for all exposure routes. Industry practices often rely on historical use and anecdotal evidence, particularly in fragrance applications. Regulatory ambiguities exist in certain regions, necessitating careful review of local guidelines.

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
• Toxicology section covers oral, dermal, inhalation
• Regulatory section mentions US, EU, UK, Asia, Latin America
• Includes section 5a for 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 2026-09-13 06:13:15 GMT (p2)