ISO INTERNATIONAL STANDARD 21149 Second edition 2017-06 Cosmetics Microbiology Enumeration and detection of aerobic mesophilic bacteria CosmétiquesMicrobiologieDénombrement et détection des bactéries aérobies mésophiles Reference number IS0 21149:2017(E) os1 International Organization for Standardization @ IS0 2017 ZHEJIANG INST OF STANDARDIZATION C1 5956617 vided by IHS underI ted without license from IHS IS0 21149:2017(E) COPYRIGHTPROTECTEDDOCUMENT IS02017,PublishedinSwitzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form written permission. Permission can be requested from either ISO at the address below or ISO's member body in the country of the requester. ISOcopyrightoffice Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org Internatinair PrganizationforStandardization icensee-ZHEJIANG INSTOF STANDARDIZAoISQ07 -All rights reserved Not for Resale, 2017/8/21 02:13:25 etworking permitted without license from IHS IS0 21149:2017(E) Contents Page Foreword ..V 1 Scope .1 2 Normative references ..1 3 Terms and definitions 4 Principle .2 4.1 General .2 4.2 Plate count .2 4.3 Membrane filtration .2 4.4 Detection of bacteria by enrichment. .3 5 Diluents, neutralizers and culture media ..3 5.1 General 3 5.2 Neutralizing diluents and diluents 5.3 Diluent for the bacterial suspension (tryptone sodium chloride solution) .4 5.4 Culture media. ..4 6 Apparatus and glassware ..7 7 Strainsofmicroorganisms ..7 8 Handling of cosmetic products and laboratory samples 9 Procedure 1 9.1 General recommendation .7 9.2 Preparationoftheinitialsuspension .7 9.2.1 General. 7 9.2.2 Water-miscible products .8 9.2.3 Water-immiscible products .8 9.3 Counting methods .8 9.3.1 Dilutions for counting methods .8 9.3.2 Plate-count methods .8 9.4 Enrichment. .9 9.4.1 General. .9 9.4.2 Incubation of the sample ..9 10 Counting of colonies (plate counts and membrane filtration methods) 11 Detection of growth (enrichment method) 12 Expression of results .10 12.1 Method of calculation for plate count .10 12.2 Interpretation. ..11 12.3 Examples ..11 12.4 Detection after enrichment. .13 13 Neutralization of the antimicrobial properties of the product ..13 13.1 General ..13 13.2 Preparation of inoculum. .14 13.3 Suitability of counting methods .14 13.3.1 Principle. ..14 13.3.2 Suitability test of the pour-plate method ..14 13.3.3 Suitability of the surface spread method ..14 13.3.4 Suitability of the membrane filtration method .14 13.4 Suitability of the detection method by enrichment .15 13.4.1 Procedure.. ..15 13.4.2Interpretation of results. .15 13.5 Interpretation of suitability test results. ..15 14 Test report ..16 iii nsee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 without license from IHS