Table 1.

Comparison of risk and impact assessments relevant to gene drive applications

	Strategic Environmental Assessment [SEA] [16, 17]	Environmental & Social Impact Assessment [ESIA]a [18]	Environmental Risk Assessment [ERA] [7, 12, 54, 55]
Purpose	Supports political and policy level decision-making	Supports decision-making on specific projects	Supports decision-making on specific products
Scope	Policy, plans and programmes	Specific projects	Specific projects
Legislative basis	National and EU environmental regulations	National and EU environmental regulations	International law and national biosafety legislationb
Guidance	Extensive documentation, including from WHO [75], UNEP [76, 77], World Bank [78], OECD [79, 80] and EU [81]	Extensive documentation, including from WHO [82], World Bank [78], International Finance Corporation of the World Bank Group [83], African Development Bank Group [84], UNEP [76, 77] and EU [85]	Extensive documentation, including from CBD [11], EFSA [7, 12], NASEM [9] and WHO [8]
Number of exercises envisaged	Single for a general class of intervention (e.g. low threshold gene drive for malaria control)	Single for a specific release at specific location but likely to be multiple based on specific context and geography	Likely to be multiple, arising from different sponsors and assigned assessors
Sponsor	Developer	Developer	Developer; Organization independent of developer; Regulatorc
Assessor	Organization independent of developer	Organization independent of developer	Developer; Organisation independent of developer; Regulatorc
Extent of engagement	Public facing and participative; Stakeholders engaged throughout processd; Data collection by interviews, focus groups, and desk-based work	Public facing and participative; Stakeholders engaged throughout processd, Data collection by interviews, focus groups, and desk-based work	Principally agency-applicant interaction; Engagement with broad experts on technical issues and parameters at discrete stages of assessment; Stakeholder engagement in problem formulation and model and scenario developmente
Parameters	Sustainability in relation to social, economic, health, environment endpoints and cumulative impacts, examination of alternatives to proposed intervention	Environmental, social, economic, and health endpoints, drawing on SEA and ERA endpoints	Biosafety endpoints on environment and health
Analysis type	Qualitative	Qualitative	Probabilistic; Qualitative; Combination of both of the aforementionedf
Role of post-release monitoring	None	Monitoring and audit as set out in Environmental and Social Management Plan to mitigate negative or enhance positive impacts of application	Post-Marketg Environmental Monitoring to assess risks and uncertainties identified and confirm hypotheses in the ERA, including on temporal or spatial scales and reversibility [12]

^aAlso known as Environmental, Socioecomonic and Health Impact Assessment (ESHIA) or Environmental Impact Assessment (EIA) in some jurisdictions

^bThe Cartagena Protocol on Biosafety to the Convention on Biological Diversity (CBD) is an international agreement that has entered into force in 173 countries, with notable exceptions such as Argentina, Australia, Canada, Israel and the United States of America

^cFor early gene drive applications, it is anticipated that all three types of potential sponsor and assessor are likely to be involved

^dFor gene drive applications, these assessments are anticipated to take place over circa two to three years

^eIn the EU, there is a mandatory engagement with the public for all GMOs that are environmentally released. The engagement is in the form of commenting on draft decisions. In this article, in ERA of gene drive applications we recommend wider engagement of experts and publics than has previously been the case with ERAs for conventional LMOs or GMOs (see Recommendations One, Four, Seven, Eight and Nine)

^fIn this article, we recommend using a combination of probabilistic and qualitative approaches to ERA for gene drive applications (see Recommendation Seven)

^gIn the case of gene drive applications, there would likely be a monitoring requirement even if the release was for pre-market trials