Citronellal

What is Citronellal?

Citronellal is an organic compound classified as an α,β-unsaturated monoterpenoid aldehyde, naturally extracted from essential oils of plants like Cymbopogon nardus (citronella grass), Eucalyptus citriodora, and Melissa officinalis (lemon balm). Its chemical structure, 3,7-dimethyloct-6-enal, gives it a volatile nature ideal for perfumery. In cosmetic formulations, it falls under the fragrance ingredient category, commonly found in creams, lotions, shampoos, and perfumes. It functions by evaporating slowly to release a bright, lemon-rose scent, defining the product's aroma profile. Additionally, it acts as a masking agent, overlaying less desirable smells from synthetic or natural raw materials, thereby improving the overall user experience without altering the product's texture or stability.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1-2 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Fragrance ingredient
Contributes scent character and/or masks base odors, shaping the overall sensory experience of the formula (subject to allergen and IFRA considerations).
Masking
Reduces perception of unpleasant odors or tastes by neutralizing them or covering them with more acceptable sensory notes.

Benefits

Delivers a vibrant, fresh citrus scent to enhance product appeal.

Neutralizes off-odors from other formula components.

Supports non-comedogenic formulations with a rating of 0.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Individuals enjoying scented skincare for sensory pleasure.
People with known fragrance sensitivities or allergies.
Users seeking natural-derived fragrance notes.
Individuals prone to contact dermatitis.
Those with normal skin tolerant to low-level perfumes.
Users preferring unscented, minimalist products.

Safety Notes

  • Assessed as low hazard (EWG 1-2), but potential for skin sensitization exists.
  • Follow IFRA guidelines for safe usage levels in cosmetics.

Frequently Asked Questions about Citronellal

What does citronellal smell like?

It offers a fresh, lemony scent with subtle rosy undertones, derived from plant essential oils.

Is citronellal comedogenic?

No, it has a comedogenic rating of 0, suitable for acne-prone skin.

Can citronellal cause skin reactions?

It may sensitize some users as a fragrance allergen, so patch testing is advisable.