Political ecology pushes back against the apolitical and ahistorical ecologies frequently found in mainstream scientific accounts of nature and the environment, and has increasingly focused on how scientific knowledge is 'socially constructed.' In this article, we argue for political ecological engagement with the highly influential knowledge-to-action (KTA) movement in science about health and the environment. We introduce KTA using results of a survey conducted under the auspices of a Canada-Latin America-Caribbean 'ecosystem approaches to health' (ecohealth) collaboration, and then narrow our focus to a single illustrative ecohealth project, dealing with the health impacts of small-scale gold mining in southwestern Ecuador. We employ an ecology of knowledge framework for integrating insights from science and technology studies, illustrating the interacting actors, material artifacts, institutions and discourses involved in not only the generation but also the application of health-environment science. The origins of ecohealth research in the Americas reflect interacting epistemological and political factors, as sophisticated, complex systemic analyses of health-environment interactions occurred amidst increasing neoliberalization of knowledge production. Simultaneously, corporate actors such as large mining companies influenced both the distribution of healthdamaging environmental conditions in the Americas, and the ways in which they were studied. This analysis motivates our advocacy of specifically political ecologies of health-environment knowledge, in which inequitable power dynamics and non-human actors are foregrounded in studies of the social production and application of science. The political ecology of knowledge framework that we envision would allow for simultaneous consideration of how societal contexts influence scientific knowledge production, and how the resulting knowledge can be better applied to protect the health of communities facing environmental injustice. Key words: ecohealth; mining; praxis; science and technology studies; knowledge-to-action; Canada; Ecuador Résumé L'écologie politique remet en question las explications apolitiques et anhistoriques fréquemment rencontrées dans les compte-rendu scientifiques sur la nature et l'environnement et met de plus en plus l'accent sur la manière dont la connaissance scientifique est socialement construite. Dans cet article, nous soutenons la pertinence de l'écologie politique pour le mouvement « du savoir à l'action », très influent dans les sciences de la santé de l'environnement. Nous présentons la perspective « du savoir à l'action » en nous appuyant sur les résultats d'une enquête menée dans le cadre d'une collaboration Canada-Amérique latine et Caraïbes sur les approches écosystémiques à la santé (écosanté), pour ensuite concentrer notre attention sur un unique projet écosanté, qui porte sur les effets sur la santé de l'extraction de l'or à petite échelle dans le sud-ouest de l'Équateur. Nous employons un cadre conceptuel d'écologi...