ALASTAIR J. GILCHRIST
Gilchrist Technical Services, Newcastle-upon-Tyne, United Kingdom

Abstract

Consumers are very aware and many are concerned about the materials used to manufacture cosmetic products. Preservatives often attract attention and rightly so because they are reactive materials which perform an essential role protecting products from many challenges throughout their entire lifecycle. There is one challenge that preservative systems should not have to deal with: that is the risk of microbiological contamination from raw materials, components or during production.
In this article we discuss the basic requirements for manufacturing cosmetic products which ensure that the added preservatives are not depleted during the production process and levels of preservatives are optimised to protect the products without exposing the consumers to higher than necessary levels of these materials to compensate for unsatisfactory production practices.

The Challenge – many cosmetic products are susceptible to microbiological contamination; this can be due to their water content for example: body washes, shampoos, conditioners, creams etc. or other products such as: solid bar products and make-up which is repeatedly challenged during normal use.

The Solution – formulators add a preservative system to these types of products to ensure the products reach the consumer in pristine condition and that they remain un-affected by microbiological contamination throughout normal use.
Preservatives are reactive chemicals which kill microbe cells and/or create an environment where it is difficult for microorganisms to multiply. Preservatives are normally used at very low levels but due to their chemical and microbiological properties they are often the focus of attention for regulators and consumers. Over use of preservatives can lead to sensitisation so it is important that their use is minimised and consumer exposure to the limited number of good preservative molecules is limited. There are alternative ways of protecting products from microbiological contamination such a ...