Preserving cosmetics – is nature winning?

The cosmetics industry has seen more rigorous regulation in recent times. In the European Union (EU) the manufacture of cosmetics is now governed by the EU Cosmetics Regulation (EC) 1223/2009. The previous EU Cosmetics Directive (76/768/EEC) and the UK Cosmetic Products (Safety) Regulations were repealed from 11 July 2013.

The new regulation requires cosmetic products to be made using good manufacturing practices (GMP). It also means that manufacturers have a dual responsibility with respect to the micro-biological quality of products. The first is to ensure that the product is free from the number and types of micro-organisms that could affect product quality and consumer health. The second is to ensure that micro-organisms introduced during normal product use will not adversely affect product quality or safety.

As many cosmetic products consist of water and other nutrients and are often stored for long periods in warm and humid conditions, such as bathrooms, they can be ideal breeding grounds for microbes. Traditionally, this issue has been effectively dealt with by using one of many known preservatives. Ideally, such a preservative needs to be: broad spectrum with activity against bacteria, yeasts and moulds; effective for long periods (as long as the product shelf life); odourless and colourless; heat stable; and effective at the target pH of the product.

But many factors in the cosmetics sector have changed recently: product usage has increased, leading to sensitisation issues for some consumers. The toxicological profiles of some preservatives have also been deemed not suitable for frequent use. In addition, consumers want milder, ‘natural’ cosmetics – largely based on a false premise that natural is ‘good’ and synthetic is ‘bad’ for the body. These changes provide a unique challenge for the microbiologist.