Too late. Nanoparticles have already irreversibly permeated the ecosystem.

Since long before Man, of course.

Being afraid of "nanoparticles" is something like being afraid of "chemicals"... in the fully silly sense. You need to be afraid of something specific, not the general term.

And I'm actually pretty down with a "presumed guilty until innocent" for specific, demonstrably new nanoparticles. (Most, if not all, carbon forms aren't going to be able to meet that bar, BTW.) Given the history of science and biology, that's not irrational. Generalized fear of anything "nanoparticle" is, though. The biological world has been nanoparticling just as it's been nanomachining for a lot longer than we've been here to worry about it.

I don't have the finger bandwidth to caveat every statement I make. Yes _new_ nanoparticles. I could make a new nanocoating, apply it to everything and then when it turns out to not by safe, my Inc can fold and I can continue on my merry existence. Nanoparticle toxocology is a complex field. And these _new_ substances penetrate cells walls very readily. It isn't antiscience to question the harm these things can do.

If nanotubes exist in car exhaust and buckyballs in candle soot then we've already performed a huge experiment on loads of people. Life expectancy is still increasing...

"every mouthful of food you and I have ever taken contained many billions of kinds of complex molecules whose structure and physiological effects have never been determined—and many millions of which would be toxic or fatal in large doses. We cannot doubt that we are daily ingesting thousands of substances that are far more dangerous than saccharin—but in amounts that are safe, because they are far below the various thresholds of toxicity. But at present there is hardly any substance except some common drugs, for which we actually know the threshold."

E. T. Jaynes

Life expectancy is a really poor metric. When accounting for the average life expectancy due to huge drop in infant mortality, LE has made very low gains at a high economic and medical cost. I was commenting that if naturally occurring nanoparticles as created in combustion are getting lodged into tissue, that synthetic nanoparticles have the same opportunity. Combustion byproducts are already known carcinogens.

>life expectancy is still increasing...*

Yet cancer, Alzheimer's, autism, etc. are on the rise.

Cancer and Alzheimer's are on the rise because life expectancy is increasing.

Nope. That only explains a portion of the increase.

Got a convincing and well-sourced statistical argument on that one?

Yes. Do you for your declaration?

Because we are better at diagnosing them then years ago. It does not mean that there are more cases of "cancer, Alzheimer's, autism, etc.". People diagnosed with Asperger syndrome would be called quirky, or plainly weird twenty years ago.

Nope. Doesn't explain it away. Real rates are rising.

I agree with you that these particles should be studied for their potential health and environmental impact, but combustion has been around much longer than humanity. I think that not all these particles are made equal and that being said I don't think that the nanotubes found in this study are much like what we are trying to create for technological purposes. They are probably very short/small and the article mentioned "[these] nanotubes are unlikely to have the cancer-causing potential of asbestos fibres, which are much larger and can get trapped in the lining of the lung." I believe their impact should be studied but there are also many other combustion products that probably have a larger negative impact.

My comment is directed at synthetic nanoparticles, not historically present forms. Waiting until it is determined that nanoparticles are unsafe is too long. These things need to be proven safe before being allowed in the environment.

Can you explain the difference between "synthetic" and "historically present" in a way that doesn't ascribe some inexplicable magic to the existence of man?

Not even that, but rather, the last [n] years of man in particular!

It has been found that various organisms can degrade carbon nanotubes, so they won't irreversibly permeate the ecosystem[0]. But we really shouldn't be dumping them into the air.

[0] http://www.nature.com/nnano/journal/v5/n5/full/nnano.2010.44...

Just because horseradish can break down nanotubes doesn't mean I can inject into the cells I already have. The existence of a catalyst doesn't make nanotubes suddenly safe.

Fortunately, that's not what your parent poster said.

And I can't read the whole paper since it is paywalled.

> We have shown previously that single-walled carbon nanotubes can be catalytically biodegraded over several weeks by the plant-derived enzyme, horseradish peroxidase1.