Antimicrobial, Preservative, and Hazard Assessments from Eight Chemical Classes

Area of Science:

• Consumer product safety
• Antimicrobial efficacy
• Toxicology

Background:

• Preservatives prevent microbial contamination in consumer products, ensuring safety and stability.
• Common preservatives like isothiazolinones and formaldehyde-releasers pose human and environmental hazards.
• Developing safer alternatives is challenging due to efficacy and safety trade-offs.

Purpose of the Study:

• To identify safer preservative alternatives with reduced human and environmental hazards.
• To evaluate a broad range of substances for antimicrobial efficacy and safety.
• To enable informed selection of preservatives balancing performance and risk.

Main Methods:

• Screened 130 substances from eight functional classes for antimicrobial activity against *Aspergillus brasiliensis* and *Pseudomonas aeruginosa*.
• Assessed high-performing compounds for human and environmental hazards.
• Tested promising candidates in model home care formulations using USP-51 guidelines.

Main Results:

• Identified caprylhydroxamic acid and caprylyl glycol as effective preservatives.
• These compounds demonstrated improved toxicity profiles compared to isothiazolinones and formaldehyde-releasers.
• Highlighted the inherent trade-offs between antimicrobial activity and hazard profiles across chemical classes.

Conclusions:

• Caprylhydroxamic acid and caprylyl glycol represent safer preservative options for consumer products.
• This research provides a framework for developing preservatives that balance efficacy with reduced toxicity.
• Safer preservative development requires careful consideration of both performance and health/environmental impacts.