Preservative efficacy testing

The efficacy testing of preservatives in a wide range of products from paints and adhesives to hand lotions and cleaning products is performed routinely at IMSL. Methods such as the IBRG challenge methods (e.g. IBRG PDG15-007, IBRG P16-001) are utilised which employ organisms known to contaminate the products under test, as well as those described in the various the Pharmacopeia. The organisms and incubation conditions used can be modified so that they are relevant to your product and help predict the performance of the preservative used. Ageing and pre-treatment of materials prior to testing, normally by prolonged periods at elevated temperatures, can also provide useful information about the stability of the preservative within the matrix and can help predict the shelf life of products.

Studies can also be designed to examine interactions and IMSL makes extensive use of statistical tools to optimise such investigations, helping to produce pre-screening cascades that lead more efficiently to the selection and validation of final preservative regimes.

Tests are also performed on finished goods such as plastics, textiles and surface coatings to determine both their susceptibility to and resistance to microbiological growth and spoilage. As well as standard test protocols such as BS3900 Part G6 and BRG DSP19-004 (resistance of paints to fungal and algal growth), ISO 846, ASTM D3273, EN15457, EN15458 etc, products can also be tested under conditions that simulate better their intended use and after pre-conditioning (eg leaching), to explore their durability.