In the current global environmental crisis medical aid and disaster relief is given by the UN and its branches, by governments and by NGOs, who regard it as their duty to address large-scale humanitarian catastrophes. The duty to give medical aid rests on traditional interpretations of health security and on the bioethical imperatives to relieve suffering and to save lives. However, those principles are not easily reconciled in the current situation of global environmental change and the threats it poses to human security. The global demand for health care has already outpaced resources in many regions, and those resources are likely to decline further. An ethic based on more comprehensive concepts of human security can lessen the contradictions between ethical priorities because it takes into account environmental security. However, that approach leads to clashes with common interpretations of human rights, including the so-called right to health care. The argument presented in this paper states that, under the imperative of ensuring the survival for humanity in acceptable and sustainable ways, the latest generation of human rights pertaining to health care and environmental quality have become ungrantable. While this does not render them negligible, it does necessitate a new approach to global development aid and health security, with severe consequences for individual autonomy.