Definitions.

‘Health security’ — the subjection of health to ‘security’ frameworks — and ‘planetary health’— the study of human health impacts of the degradation of planetary ecosystems — have emerged in the last decades as prominent global health fields. However, limited literature connects them, particularly incorporating critical perspectives. We explored interactions between these approaches conceptually, institutionally, and empirically, aiming to chart a conceptual genealogy of these interactions. To this end, we conducted a scoping review using Arksey and O’Malley’s method and Levac’s revisions, exploring health, security, and ecology literatures. We identified 75 eligible sources of 10,352 screened and synthesised findings inductively using Braun and Clarke’s thematic approach. Based on our findings, we synthesised five themes relating to how environmental degradation is framed as a security threat, the role of biosecurity and broader ‘non-traditional’ security threats, institutional ties between health and environmental governance, environmental costs of militarised health responses, and the rise of new technologies for managing planetary health risks. We found multiple descriptions of environmental health as ‘crisis’ and ‘security’ issue, yet health security’s scope remained limited to containment of emerging infectious diseases, rather than prevention or broader health concerns. This initial exploration across disciplinary literatures of conceptual interactions between planetary health and health security showed both mobilising the language of ‘security’ to frame health issues yet raised concerns over inequitable experiences resulting from this framing. An overt emphasis on containment over prevention and tacit commitments to the protection of some lives over others could result in asymmetrical health experiences, rendering some geographies and populations ‘sacrificial’ in their health risks.