TRIETHYL CITRATE

Triethyl citrate or citric acid ester is a solvent and diluent and is considered non-sensitizing to the skin. It is even approved for use in food. (1)

A study also investigated the effectiveness of a preparation containing triethyl citrate and ethyl linoleate on acne vulgaris. Triethyl citrate is hydrolyzed by C. acnes (which can cause acne under certain circumstances) to diethyl ester and monoethyl ester of citric acid and to citric acid itself. The microenvironment of the pores consequently becomes acidic, leading to reduced growth of C. acnes, inhibition of bacterial lipases, and modulation of the keratolytic effect. (2)

(1) Fiume, M. M.,Heldreth, B. A.,Bergfeld, W. F.,Belsito, D. V.,Hill, R. A.,Klaassen, C. D.,... & Andersen, F. A. (2014). Safety assessment of citric acid, inorganic citrate salts, and alkyl citrate esters as used in cosmetics. International journal of toxicology, 33(2_suppl), 16-46.

(2) Charakida, A.,Charakida, M.,& Chu, A. C. (2007). Double-blind, randomised, placebo-controlled study of a lotion containing triethyl citrate and ethyl linoleate in the treatment of acne vulgaris. The British Journal of Dermatology, 157(3), 569–574.