In 2019, Global Organic Textile Standards (GOTS), the Organic Cotton Accelerator (OCA) and Textile Exchange partnered to develop the ISO IWA 32:2019 protocol (1) to create a common language among laboratories worldwide to screen for the potential presence of genetically modified (GM) cotton along the organic cotton value chain.

Following that project, the partners set out on a new initiative to bring much-needed clarity regarding the laboratories that perform testing against the international ISO reference protocol and carry out qualitative GMO testing in cottonseed, leaf, fibre and chemically unprocessed fibre-derived materials.

The global ISO IWA 32:2019 proficiency test initiative is a collaboration between GOTS, OCA and Textile Exchange with technical support from Wageningen Food Safety Research. The joint project has reached a significant milestone: fourteen laboratories from China, Germany, India, the Netherlands and Portugal have successfully passed the proficiency test. An overview of the laboratories that can currently conduct GMO testing as per the ISO IWA 32:2019 method has now been jointly published by GOTS, OCA and Textile Exchange, which constitutes an important milestone on the journey towards the widespread use of this standardised protocol.


Bringing clarity on GMO testing methods for the organic cotton sector

While GMOs are excluded from organic systems, organic isn’t a claim of absolute freedom from contamination or GMOs’ presence in organic products (2). It is a claim that GMOs are not deliberately or knowingly used and that organic producers take far-reaching steps to avoid GMO contamination along the organic cotton value chain, from farmers to spinners, to brands. To manage this, it is essential that organic cotton stakeholders can reliably test their products for the potential presence of GM cotton.

The ISO IWA 32:2019 is a globally accepted reference protocol that was developed to screen for the potential presence of genetically modified (GM) cotton. The protocol provided the organic cotton sector with an essential tool for taking all reasonable precautions to prevent GM cotton in their organic cotton produce. Since the publication of this globally accepted reference protocol, qualitative GM cotton screening as per the ISO IWA 32:2019 is mandatory within the GOTS and OCS (Organic Content Standard) supply chain and OCA’s Farmer Engagement and Development programme.

The sector now recommends using the ISO IWA 32 protocol throughout the organic cotton value chain as the only recognised method for GMO testing. Therefore, the global ISO IWA 32:2019 proficiency test initiative’s success is vital in building confidence among the industry.

Commenting on the global ISO IWA 32:2019 proficiency test initiative, OCA’s Programme Officer, Mathilde Tournebize, said: 

“As a global platform, we are committed to increasing the clarity and reliability of GMO screening for the organic cotton sector. The first results of the global proficiency test initiative have given us an overview of the laboratories that can be contacted to conduct such tests. We’re hopeful that as we see more laboratories implementing the ISO IWA 32:2019 worldwide, several rounds of proficiency tests will help us all chart the labs that can be contacted to reliably conduct GMO tests. We are proud to be working in partnership with both GOTS and Textile Exchange as we are united in our belief that this proficiency test will contribute to standardising GMO testing along the organic cotton value chain. Our ambition is to reach out to more laboratories and geographies to increase the widespread use of the ISO IWA 32:2019 protocol.”


Rahul Bhajekar, Managing Director at GOTS, added: 

“I am glad to see a high level of interest from laboratories across the world and results showing competence from producing and buying countries. We shall continue to further advance this collaboration with like-minded organisations to further develop the standardisation of GMO testing in cotton fibre products. We remain committed to ensuring that GOTS goods are free from GMOs.”


Amish Gosai, South Asia Manager at Textile Exchange, said: 

“The success of standardised testing methods depends on adaptability and uniformed results. Labs achieving a successful outcome in the proficiency test indicate both lab performance and the effectiveness of this method. We are glad to see that this initiative shows that the global ISO IWA 32 testing method gives consistent outcomes, and we look forward to more labs joining the next round of the proficiency test.”

A first step to unifying the sector on GMO screening

The ISO IWA 32:2019 proficiency test initiative will not cease with the current laboratories; the joint initiative will be repeated regularly. More laboratories are welcome to apply for the next round of proficiency test, which will be organised, once sufficient demand has been reached. The ISO IWA 32 protocol is also currently in the process of being converted to an International Standard by the ISO TC 34 / SC 16 / JWG 12 ‘Molecular biomarkers of agricultural fibres’. GOTS, OCA and Textile Exchange are participating in the working group to ensure that the organic cotton sector interests are represented.

Are you a GM cotton testing laboratory that implemented the ISO IWA 32:2019 reference protocol and are you interested in joining the next round of proficiency test? Do you have any questions about the global ISO IWA 32:2019 proficiency test initiative? Or would you like to update your contact details? Please contact Mathilde Tournebize with your query.

For more information about the global ISO IWA 32:2019 proficiency test initiative, please see below. 

1. In April 2019, after initial conceptualisation by GOTS, OCA developed the ISO International Workshop Agreement 32:2019(E) on “Screening of genetically modified organisms (GMOs) in cotton and textiles”, with strategic input from the wider organic cotton sector. The protocol provides requirements and recommendations to laboratories that perform qualitative GM cotton screening in cottonseed, cotton leaf, cotton fibre and chemically unprocessed cotton fibre-derived materials up to greige yarn and fabric. This protocol also clarifies the matrices where good quality DNA can be isolated in cotton fibre-derived materials and textiles. The protocol is the result of a consensus-based ISO International Workshop Agreement, facilitated by the Netherlands Standardization Institute (NEN). The development process included perspectives and feedback from all parties concerned (over 80 participants from 23 countries), including representatives from laboratories, cotton producers, suppliers, brands and retailers, standard bodies and governmental agencies. The technical process of the proficiency test carried out in 2020 was managed by Wageningen Food Safety Research (WFSR), the organisation that acted as a technical 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).


2. Article 4 Council Regulation (EC) No 834/2007 and Article 5 Regulation (EU) 2018/848, and IFOAM Organics International, Position Paper ‘Genetic Engineering and Genetically Modified Organisms’, 2016


Disclaimer: This proficiency test has been organised to obtain a one-off 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 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 will be 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 shortlist of laboratories that succeeded in the proficiency test.