Global ISO IWA 32:2019 proficiency test initiative 2025

Organic cotton is a claim that genetically modified organisms (GMOs) are not deliberately or knowingly used and that organic producers take far-reaching steps to avoid GMO contamination along the organic cotton value chain1, from farmers to spinners, to brands. To confirm that such steps have been taken, it is essential that organic cotton stakeholders can reliably test their products for the potential presence of GM cotton.

The ISO IWA 32:2019 protocol was developed to create a common language among laboratories worldwide to screen for the potential presence of GM cotton along the organic cotton value chain. Since its publication, qualitative GMO testing of cotton and textiles is mandatory within the GOTS and OCS supply chain and OCA’s Farm programme and is to be performed by appropriately qualified testing laboratories using the ISO IWA 32:2019 protocol.

The Global Organic Textile Standard, the Organic Cotton Accelerator, and Textile Exchange set out the global proficiency test initiative to bring clarity regarding the laboratories that perform testing against the ISO IWA 32:2019. Please find below the list of laboratories that have been confirmed to have the necessary competence to carry out qualitative GMO testing in greige cotton products as per the ISO IWA 32:2019 worldwide. This list is compiled based on labs’ satisfactory performance during the latest round of a proficiency test organized every two years.

The technical process and the performance evaluation of the proficiency test for qualitative cotton screening according to ISO IWA 32:2019 were managed by Wageningen Food Safety Research (WFSR), the organization that acted as a project leader for the development of the ISO IWA 32:2019 and is accredited for performing proficiency tests according to the ISO/IEC 17043:2010 Conformity assessment – General requirements for proficiency testing (not specifically in the field of GMOs).

 As the ISO IWA 32:2019 protocol established that GMO screening in cotton and textiles can only be reliably carried out in cottonseed, cotton leaf, cotton fiber, and chemically unprocessed cotton fiber- derived materials up to greige yarn and fabric, GM cotton testing should not be carried out in chemically processed cotton.

 In alignment with international standardisation efforts, Global Organic Textile Standard, the Organic Cotton Accelerator, and Textile Exchange recognise that ISO 5354-1 and ISO 5354-2 have officially replaced ISO IWA 32 by April/June 2025. The current proficiency test was conducted using the ISO IWA 32 methodology, acknowledging a transition period required for the adoption of the new ISO 5354 methods. Moving forward, all subsequent proficiency tests will be organised in accordance with the ISO 5354 methods, ensuring consistency with global best practices and enhanced reliability in testing procedures.

Overview of laboratories

List of laboratories that can carry out qualitative GMO testing in greige cotton products as per the ISO IWA 32:2019 according to the global ISO IWA 32:2019 proficiency test initiative organised in 2025.

Are you a GM cotton testing laboratory that implemented the ISO IWA 32:2019 reference protocol and are you now interested in joining the next proficiency test round in Q1 2027? Do you have any questions about the global ISO IWA 32:2019 proficiency test initiative 2025? Or do you want to update the organisers about your contact details or your accreditation status against ISO/IEC 17025:2017 for GM cotton screening? Please contact Chenyue Li, OCA’s Environmental Impact Officer, with your query:

About the ISO IWA 32:2019

*The ISO International Workshop Agreement 32:2019(E) on "Screening of genetically modified organisms (GMOs) in cotton and textiles" is an international reference protocol that was developed in April 2019 under the initiative of the Organic Cotton Accelerator, together with the organic cotton sector and after initial conceptualisation by the Global Organic Textile Standard (GOTS), with the aim of creating a common language amongst laboratories when testing for GMO presence in greige cotton samples. This protocol for qualitative GMO-screening in cotton and textiles provides requirements and recommendations to laboratories that perform GMO analysis in cottonseed, cotton leaf, cotton fibre and chemically unprocessed cotton fibre-derived materials up to greige yarn and fabric.

With more laboratories implementing the ISO IWA 32:2019 in 2020 worldwide, the organic cotton sector will benefit from having an overview of the laboratories that can currently conduct GMO testing as per the ISO IWA 32:2019 protocol globally. This overview has been provided thanks to the organisation of a proficiency test at laboratories that had already implemented or were in the process of implementing the ISO IWA 32:2019 method in December 2020. The technical process of the proficiency test has been managed by Wageningen Food Safety Research (WFSR), the organisation that acted as a project leader for the development of the ISO IWA 32:2019 and is accredited for performing proficiency tests according to the ISO/IEC 17043:2010 on ‘Conformity assessment — General requirements for proficiency testing’ (not specifically in the field of GMOs).

(1) As an international body, it is important for the standard owner that the laboratories can follow international standards for uniform and repeatable testing operations. An accreditation of the laboratory to ISO/IEC 17025:2017 verifies the competence, impartiality and consistent operation of laboratories.

Disclaimer: These proficiency test results have been organized to obtain an up-to-date overview of the laboratories that can currently conduct GMO testing as per the ISO IWA 32:2019 protocol. The participating laboratories have been invited based on direct applications from laboratories as well as existing collaborations with the Global Organic Textile Standard, the Organic Cotton Accelerator, and Textile Exchange and/or that of their partners, to the best of their knowledge. The results have been made publicly available for informational purpose only. No radical business decision should be made from the results of this proficiency test regarding the current or future cooperation with laboratories that did not participate or do not appear in the short-list of laboratories that succeeded in the proficiency test.