Globally existential threats due to ‘overpopulation momentum’ together with the top-heavy age structure leave by now no alternative to radical technological adaptation for anything that wants to survive 'long term'.  It is strictly too late to ‘go green’ except via a novel take on what constitutes ‘green’, including synthetic biology.  Hyped for a long time, nanoscience is still largely in its pioneering phase.  However, it matures as we speak and soon, as it becomes true nanotechnology, it will leave the hype far behind.


Is nanotech harmless?  Mother Nature has adapted via nanotechnology all along, namely with nanometer sized replicators and catalysts.  The latter we call “enzymes”, but catalysts they are nonetheless.  Humans are nanotech robots that nature made, complete with what may equally count as “artificial intelligence”.  Thus, one is tempted to brush fears about dangers away, much like the naturally existing interactions of cosmic radiation in atmosphere and plants refute the alleged existential dangers due to the Large Hadron Collider (LHC) or Genetically Modified Organisms (GMO), respectively.  However, nano being basically bio, this equivalence implies that nanotech is also at least as dangerous as biotech.  But it would be missing the real dangers if we were to stop here and merely list the increasingly long list of bad news about, for example, nano-junk accumulating in surprising locations and it being highly biologically active in unexpected ways.


Nanotech is intrinsically much more dangerous then biotech.  For example, although organisms can easily be evolved to synthesize metallic or anyways highly complex compound-material nanostructures (just look at your teeth), nature has never touched metallic crystals as bio-catalysts; and for good reasons: they are so reactive that nature could never before handle them.


Nature’s co-evolution of all systems with their environment will be sped up, which is natural and no danger to nature itself in any meaningful sense, however, the pace will be larger than human biology (even if techno enhanced) and society can handle.  Basically, this is yet another way, next to the production of AI/robotics, in which we ensure our own demise. The nanotech researchers’ engineering mindset and its enthusiasm for pushing self-assembly and evolutionary methods render nanotechnology dangerous beyond sporadic health, safety and environmental concerns.  Say hello to an exciting new, globally existential risk.


Additionally and ironically (given its especially hazardous status), nanotechnology is afflicted by relatively low ethical standards and an almost unscientific alchemist culture.  Bio-research is close to medicine, and an ethically caring culture dominates that research community; high status of advanced statistics to avoid bias and concerns about unintended consequences are central to such fields.  When comparing sciences like high energy physics (where everything is checked and criticized as a rule), chemistry, or medicine, nanotechnology comes in far below even on such basic measures as regard for the scientific method, say reproducibility.  There is an ‘only-good-news’ attitude in nanotech peer-review, where critical work is seen as worthless or treason rather than necessary for good science.


There are ethics committees and conferences on governance and oversight and all the usual nonsense that is primarily there for show and the careers of the involved, but none of it can have any substantially directing effect on future evolution, which will go on in its integration of the technological substrate into the biosphere.  Human participation, previously vital for advanced social and technological evolution, is now turning from being an already overabundant resource, shaped and discarded much like any other cheap material, to something that rather resembles a polluting byproduct.  In a large fraction of futures, it will stay around abundantly for a while, like oxygen did, but there is no consistent future in which humans will not have been altered to be basically something else entirely (relative to our current self-identification).