Getting to grips with nanomaterial toxicity

December 15, 2008

Introducing MINChar—a new community initiative to support effective material characterization in nanotoxicity studies.

logo_simpleHere’s a tough one:  Imagine you have a new substance—call it substance X—and you run some tests to see how toxic it is.  But you’re not quite sure what substance X is.

You know that it is a powder, and it is supposed to have chemicals x y and z somewhere in it.  But you don’t know how small the particles are, what shape they are, whether chemical z is on the surface of the particles or inside them, whether the particles all clump together when shoved into the test system or whether they can’t get far enough away from each other after being administered, or whether there is something else present in substance X that really shouldn’t be there.

Now imagine your tests show that substance X looks like it could be rather dangerous.  How do identify which aspect of the material is causing the problem, so you can go about fixing it?

Or imagine someone else wants to repeat your work.  Or they want to compare your data with another study.  How do you know that the substance being used in other studies is the same as substance X, and not simply a crude approximation?

The scenario is somewhat hypothetical, but the issues are very real.  And they have dogged the field of nanotoxicology for over a decade. Read the rest of this entry »


Toxic particles and trivial pursuits*

November 23, 2008

First impressions of the ICON EHS Database Analysis Tool

What do you do this holiday season when the turkey’s lost its appeal, you’ve seen every movie worth watching ten times over, and conversational déjà-vu sets in?  If you are really desperate, you could play “nano-trivia”—and thanks to the fine folks at the International Council On Nanotechnology (ICON) you now have the perfect widget to help craft those cunning questions that will have your nearest and dearest wracking their brains.

Questions like “between 2000 and 2006, what percentage of scientific papers addressing the toxicity of carbon-based nanomaterials considered exposure via mucous membranes (or the skin)?”

OK, so maybe playing “toxic particle trivial pursuits” is the last resort of the desperate, and likely to result in an ever-decreasing circle of close friends.  But for all that, the new ICON Environmental Health and Safety Database Analysis Tool has its merits… Read the rest of this entry »


Nanotoxicologists self-assemble

September 9, 2008

If you evaluate the toxicity of an engineered nanomaterial, how far can you trust your results?  If someone else repeats your tests and gets a different answer, did they do it wrong? Did you?  Or was the material used different in some subtle but nevertheless important way?

These are questions that have dogged nanotoxicologists for years, and have undermined many a study.  But help is at hand—a group of scientists have decided to grasp the nettle and start working together to unravel these rather knotty challenges. Read the rest of this entry »