Mega-sized concerns from the nano-sized world: the intersection of nano- and environmental ethics.

As rapid advances in nanotechnology are made, we must set guidelines to balance the interests of both human beneficiaries and the environment by combining nanoethics and environmental ethics. In this paper, I reject Leopoldian holism as a practical environmental ethic with which to gauge nanotechnologies because, as a nonanthropocentric ethic, it does not value the humans who will actually use the ethic. Weak anthropocentrism is suggested as a reasonable alternative to ethics without a substantial human interest, as it treats nonhuman interests as human interests. I also establish the precautionary principle as a useful situational guideline for decision makers. Finally, I examine existing and potential applications of nanotechnology, including water purification, agriculture, mining, energy, and pollutant removal, from the perspective of weak anthropocentrism using the precautionary principle.