EP Challenge Test
European Pharmacopoeia - 5.1.3 “Efficacy of Antimicrobial Preservation"
This Preservative Efficacy Test (PET) or cosmetic challenge test, is essential for assessing the safety of cosmetic products susceptible to spoiling, such as those which require preservation or that contain water. According to the EU Cosmetic Products Regulation, for these cosmetic products it is a legal requirement to include the results of a challenge test in the Cosmetic Product Safety Report (CPSR) before they can be sold.
The European Pharmacopoeia test method is commonly used for products sold in the European Union and United Kingdom but is recognised worldwide.
Buy EP tests
EP, USP or ISO?
PET test details
European Pharmacopoeia (EP)
European Pharmacopoeia (EP) - PET tests
Which EP Test?
How Long?
Test Procedure
EP, USP or ISO standard PET test?
The challenge test protocol that you require is governed by the market that you intend to sell your products into.
The EP test method for Europe / UK and the USP method for the USA are well established protocols, offering formulators confidence that their products are robustly protected. The methods are also accepted in many other territories.
The ISO 11930 method has been introduced more recently. Although it is considered a less stringent test than the EP or USP, unlike these Pharmacopoeia test methods, ISO 11930 was designed specifically with cosmetics in mind.
| EP | USP | ISO | |
|---|---|---|---|
| Incubation (days) | 28 | 28 | 28 |
| Sample required (g) | 250 | 250 | 250 |
| Total Species | 4/5 | 5 | 5 |
| Staphylococcus aureus | ● | ● | ● |
| Pseudomonas aeruginosa | ● | ● | ● |
| Candida albicans | ● | ● | ● |
| Aspergillus brasiliensis | ● | ● | ● |
| Escherichia coli | ○ | ● | ● |
PET test details
The major differences between the methods are noted in the table opposite. For oral care products, testing against Escherichia coli is an additional requirement of the EP method. The cost of a cosmetic challenge test varies by the type chosen.
The ISO 11930:2019 method uses less stringent pass criteria compared to the pharmacopoeia methods.
European Pharmacopoeia (EP)
A European Pharmacopoeia 5.1.3 test (EP) may sometimes be referred to as a challenge test, Preservative Efficacy Test (PET) or Antimicrobial Effectiveness Test (AET).
An EP/PET test must be carried out on cosmetic products prone to microbial contamination in order to comply with the EU Cosmetic Products Regulation (EC 1223/2009). The EP test quantifies the effectiveness of the preservatives in the cosmetic formulation against microbial contamination.