TWN Info Service on Biodiversity and Traditional Knowledge (Oct25/04)
14 October 2025
Third World Network

Dear Friends and Colleagues

TWN Briefing Note for SBSTTA-27 - Risk assessment of LMOs

The Convention on Biological Diversity’s Subsidiary Body on Scientific, Technical and Technological Advice (SBSTTA) will meet in Panamá City from 20^th to 24^th October 2025.

Parties to the Cartagena Protocol on Biosafety are expected to take up a recommendation on risk assessment and risk management of living modified organisms (LMOs), relating to further guidance materials on specific topics of risk assessment.

We are pleased to share below a TWN Briefing Note on the issue. It is paramount that further guidance on risk assessment of LMOs is precautionary and aligned with Annex III of the Protocol. This is especially in light of new and proposed LMO products that are broadening in species range, trait type, receiving environment and intended application.

With best wishes,
Third World Network

Third World Network Briefing Note for SBSTTA-27
20-24 October 2025

Risk assessment and risk management of living modified organisms
(Agenda Item 7, CBD/SBSTTA/27/6)

Background

In decision CP-11/7, the Conference of the Parties serving as the meeting of the Parties to the Cartagena Protocol on Biosafety (COP-MOP) invited Parties to submit detailed information on their needs and priorities for further guidance materials on specific topics of risk assessment of living modified organisms (LMOs), including a rationale following the criteria set out in Annex I to decision CP-9/13.

The Open-ended Online Forum on Risk Assessment and Risk Management was extended to support the analysis. Parties also established an Ad Hoc Technical Expert Group (AHTEG) to analyse information submitted by Parties and the discussions in the Online Forum, and to prepare a list of prioritized topics on which further guidance materials on risk assessment may be needed.

Submissions from Parties identified 15 topics for further guidance: 1) LM fish; 2) LM microorganisms; 3) LM algae; 4) LMOs expressing genome editing machinery for pest or pathogen control; 5) long- term and cumulative effects of genetic constructs and LMOs; 6) use of LMOs in centres of origin and in traditional agricultural systems; 7) operationalising protection goals into relevant risk assessment endpoints; 8) genome edited mammals for use in agriculture; 9) LM animals; 10) LMOs containing stacked events; 11) LMOs for food, feed and processing; 12) detection and monitoring of LMOs; 13) LMOs produced through new biotechnologies; 14) simplified procedures (Article 13) and agreements and arrangements (Article 14); and 15) transportability of data.

The submissions put forward by Parties for further risk assessment guidance reflect the evolving landscape of LMO research interests. New and proposed LMO products are broadening in species range, trait type, receiving environment and intended application. Techniques are also evolving, with several submissions reflecting the need for guidance on new engineering techniques such as genome editing.

Conclusions of the AHTEG

The AHTEG concluded that seven topics fulfilled all the criteria set out in Annex I of decision CP-9/13 to warrant further guidance on risk assessment.

Four topics were prioritised for risk assessment guidance materials[i]:

1) LM fish;
2) LM microorganisms;
3) LM algae; and
4) LMOs expressing genome editing machinery for pest or pathogen control.

Three topics were prioritised for the development of technical notes, as supplements to support more specific risk assessment considerations:

1) Long-term and cumulative effects of genetic constructs and LMOs;
2) Use of LMOs in centres of origin and in traditional agricultural systems; and
3) Operationalising protection goals into relevant risk assessment endpoints.

Prioritised topics illustrate cross-cutting risk considerations and challenges of new and emerging LMO applications

The four topics recommended by the AHTEG for further guidance illustrate numerous cross-cutting biosafety considerations that challenge existing risk assessment frameworks, guidance and methodologies. Applications are already advancing across the different topics, and in some cases already approved for release (e.g. CRISPR-expressing E.coli for chicken gut applications), or indeed released (e.g. LM salmon, LM (genome edited) nitrogen-fixing bacteria). The requests from Parties for guidance in these areas are testament to the continued need for the Cartagena Protocol to stay abreast of such LMO applications to ensure that releases into the environment do not undermine the objectives of the Convention and the Protocol.

Current risk assessment experience is lacking for all four topics, with current methods and experiences largely catered to terrestrial species, and most commonly applied to annually-cultivated crop species. No risk assessment materials specific to aquatic organisms (relevant to both fish and algae), were noted as being available by the AHTEG. Some existing materials exist for microorganisms, for example in the EU, but this has been limited to food and feed safety, and not addressing environmental release.

All four topics pose challenges to risk assessment. For example, for microorganisms, including microalgae and bacteria expressing genome editing machinery, there are significant concerns regarding their high levels of spread, dispersal and persistence capabilities and the lack of ability to control, recall or monitor this. Microorganisms are known to be capable of long-distance dispersal e.g. in rain, wind, pollen, leaf litter, waterways, soils, via human and animal microbiomes. Similarly, aquatic species such as fish have high levels of dispersal capacity across long distances. Such characteristics make the task of assessing impacts on all potential receiving environments, as well as controlling transboundary movements, challenging.

The rapid reproductive rates and evolutionary potential of microorganisms (including microalgae and those expressing genome editing machinery) also challenge the ability to predict outcomes, e.g. evolutionary changes that change host specificity and increase spillover risks. Similar challenges apply to fish with their ability to adapt, and their sensitivity to environmental interactions. This raises significant uncertainties regarding the ability to address unintended effects.

Another major concern spanning the four topics is the risk of gene flow. Gene flow via horizontal gene transfer is common in microbial species including bacteria, making the ability to control the spread of engineered traits extremely difficult, if not impossible.

There are fundamental knowledge gaps on all the topics, with regard to the lack of available baseline data on the biology of these organisms and the ecosystems they occupy, again increasing uncertainties. For microorganisms and algae, knowledge gaps remain in terms of the information required to conduct a reliable risk assessment, including on ecological roles, interactions, wider community interactions and evolutionary potential. The majority of microorganisms have not yet been identified, raising uncertainties regarding the engineering of species that live in wider, complex communities.

For LMOs expressing genome edited machinery, there is another layer of complexity. Such products encompass the release, not just of an engineered organism, but of an engineered organism that is designed to engineer organisms directly in the open environment. This thus creates two engineered organisms, and opens up unknown routes for gene flow and exposure that are no longer restrained by species barriers. It also removes the ability to assess the effects of the genome-edited organism prior to release, as the “editing” occurs directly in the field.

Technical notes point to need for holistic and contextualised assessments

Two of the topics recommended for the development of technical notes are particularly urgent and should be prioritised:

Use of LMOs in centres of origin and in traditional agricultural systems 

The Cartagena Protocol recognizes the crucial importance to humankind of centres of origin and genetic diversity. LMOs represent direct and immediate biodiversity risks when released in their centres of origin, particularly in light of the ongoing biodiversity crisis, warranting further guidance on this issue. Current guidance does not yet provide for contextualised risk assessments that incorporate local contexts and traditional agricultural systems where there may be high levels of biodiversity of wild relatives, traditional variety counterparts and non-target organisms. Special considerations are needed to assess the risks of gene flow in such contexts, and the potential impacts on genomic diversity and plasticity, as well as the impacts on diverse agricultural, ancestral and indigenous knowledges and practices. Informal or remote markets and seed exchanges may also challenge the ability to control gene flow, unintended spread and unauthorised uses. 

Long-term and cumulative effects of genetic constructs and LMOs

Requests for further guidance on “long-term and cumulative effects” reflect ongoing concerns regarding the potential harms of LMOs to people and the environment, which may not be immediately realised. This is becoming increasingly relevant and urgent as “stacked” traits and multiple events are simultaneously entering the market, complexifying the potential adverse effects and the assessment thereof. The predominance of herbicide-tolerant varieties making up the vast majority of LM crops to date also raises immediate concerns regarding the gaps in assessment of the impacts of herbicides on the LM crop as well as those consuming or exposed to them.

Further guidance should be precautionary and rooted in Annex III

The risks and uncertainties associated with the topics recommended for further guidance warrant a precautionary approach, as recommended by the AHTEG. The AHTEG further recommended that any new guidance materials or technical notes need to align with Annex III of the Protocol.

These are key in the ability to detect the full range of potential unintended effects that may arise, with aspects including, but not limited to:

1)      Assessing potential impacts of any changes occurring within an LMO, arising from all intended and unintended changes. Due to the potential for unintended effects to occur during the engineering process, or following release, e.g. evolutionary changes, strict alignment with Annex III is required.

2)      Adhering to a science-based assessment that assesses all and not just selective risk hypotheses.

3)      Maintaining the precautionary approach, anchored in the burden of proof resting on proponents to prove safety, rather than on others to prove harm.

4)      Sufficiently addressing uncertainties and knowledge gaps in order to operationalise the precautionary approach.

Recommendations

·         Support the AHTEG recommendation to develop additional voluntary guidance materials for LM algae, LM microorganisms, LMOs expressing genome editing machinery for pest or pathogen control, and LM fish.

·         Support the AHTEG recommendation to develop technical notes for priority topics of long-term and cumulative effects of genetic constructs and LMOs; and the use of LMOs in centres of origin and in traditional agricultural systems.

·         Support the conclusions of the AHTEG that the precautionary approach is integral to the objective and scope of the Protocol and further, that Annex III is foundational to risk assessment.