In Vitro Percutaneous Absorption of Dehydroacetic Acid and Benzoic Acid From Pig Skin Using the Franz Diffusion Cell...

Area of Science:

• Cosmetic Science
• Dermatology
• Analytical Chemistry

Background:

• Dehydroacetic acid (DA) and benzoic acid (BA) are widely used cosmetic preservatives in Korea.
• Regulatory limits exist for DA (0.6%) and BA (0.5%) in cosmetic products.
• Understanding the percutaneous absorption of these preservatives is vital for safety assessments.

Purpose of the Study:

• To develop and validate analytical methods for quantifying DA and BA in skin matrices.
• To evaluate the percutaneous absorption of DA and BA through minipig skin using Franz diffusion cells.
• To assess the in vivo skin absorption rates of DA and BA at various concentrations.

Main Methods:

• Validated analytical methods using LC-MS/MS for DA and BA quantification.
• Percutaneous absorption study utilizing Franz diffusion cells and dermatomed dorsal minipig skin.
• Topical application of lotion formulations containing varying concentrations of DA and BA (0.12%-0.6% and 0.1%-0.5%).

Main Results:

• Validated methods showed high linearity (r² > 0.999), accuracy (91.5%-111.7%), and precision (1.3%-10.1%).
• Total percutaneous absorption rates for DA ranged from 91.42% to 104.13%.
• Total percutaneous absorption rates for BA ranged from 51.54% to 79.10%.

Conclusions:

• Both DA and BA are significantly absorbed through the skin.
• The study highlights the importance of considering skin absorption rates in the safety evaluation of cosmetic preservatives.
• Findings support the safe use of DA and BA within permitted concentration limits, pending further safety assessments.