ANDRESS JOHNSON, KEVIN RODEN
1. Thor Specialties, Inc., Shelton, USA 
2. Thor Specialties, Wetherill Park, Australia

Abstract

The preservation of sunscreens is difficult due to the nature of sunscreen formulations and  restriction on available preservatives. The selection of an appropriate preservative package must be compatible with the sunscreen formulation and other ingredients as well as meeting marketing criteria on acceptable preservatives.
This paper discusses the requirements for consideration and provides options with some of the benefits of the selected preservatives.

INTRODUCTION

The development of preservative systems that ensure effective protection of personal care products while addressing customers concerns over their safety and perceived toxicity is becoming more and more challenging (1).
Many of the traditional preservatives listed on Annex V of the EU Cosmetic Regulation (2) are under pressure from regulatory or consumer groups. Parabens, the historical preservatives of choice for sunscreens have suffered from claims of toxicity and attacks from many groups on social media and their use is now limited due to a desire from marketers to remove controversial ingredients from their formulations. Formaldehyde donors have also been under pressure and were banned in children’s products in Minnesota. The decision has been reversed and they are now allowed with restriction on the formaldehyde level to a maximum of 0.05% (3).

Sunscreens in the USA are considered “Over The Counter” (OTC) Drugs and as a result the manufacturing of these products is highly controlled. They must be shown to be both safe and effective and must comply with all other requirements listed in the FDA’s OTC sunscreen monograph inclu ...