Subscribe to RSS Feed Login

Science News Review

Thursday
28 August 2008

Science news for the average citizen.

Are Carbon Nanotubes Dangerous Like Asbestos?

nanotubes

ScienceNews reported last week that research on mice suggests these new fullerene-based wonder-fibers may be as dangerous as asbestos in the environment. The study showed that multi-walled (rigid) nanotube fibers longer than 15 micrometers cannot be removed from sensitive organic tissues by microphages, and that this causes inflammation that could lead to asbestos-like diseases including mesothelioma, a fatal form of cancer.

The study was published in the May 20 online edition of Nature Nanotechnology, and according to the Washington Post serves as a preliminary warning that there may be serious issues with the technology that warrant very careful planning to protect industrial workers, the public and the environment as nanotube fibers become more common in consumer and industrial products.

Companies around the world produce thousands of tons of nanomaterials a year, not all of them in the form that poses the threat identified by these researchers. Nanotubes alone are expected to become a multi-billion dollar industry within the next few years. While the government pumps about $1.5 billion a year into R&D for nanotechnology, only about 5 percent of that goes into health and safety concerns.

It would be quite refreshing if, for a change, we incorporated the lessons of history as we develop this promising new technology to forestall issues related to health, safety and environmental pollution before they become just more grim statistics attached to greed over due caution. And for this reason the situation bears watching to see if identified areas of concern are simply denied and swept under a profit rug, or rationally dealt with as if humans could accept responsibility - and minimize risks - per the less than hopeful side-effects of our intelligent designs.

No CommentsContinue Reading

What Happens To Your Anti-Bacterial Soaps

JamaicaBay

The “germ-free” craze not only contributes to a generation of homebound children who have no developed resistance to real world ‘germs’ or irritants, we’ve also been warned over and over again for more than a decade that those bacteria we’re fighting will themselves develop resistance to the anti-biotics we use against them. Now a study by the Biodesign Institute at Arizona State University has traced the active ingredients in antibacterial soaps to their final resting place in the shallow sediments of estuaries into which treated wastewater is dumped.

The active ingredients traced are triclosan (TCS), which is structurally similar to dioxin, and triclocarban (TCC), a closely related compound. Biodesign Institute researcher Rolf Halden and coworkers traced these compounds to the shallow sediments of New York City’s Jamaica Bay and the Chesapeake Bay, the world’s largest estuary. Both of these compounds operate as endocrine (hormone) disruptors in mammals, much as agricultural chemicals operate to disrupt the sexual development of amphibians in the midwest.

Halden made use of concentrations of radioactive fallout from nuclear testing in the last half of the 20th century to determine how long ago the antimicrobial residues were deposited (and thus how long they’re lasting in the environment). And while core samples determined that a 1978 improvement in a Baltimore waste treatment plant did drop the levels of deposited TCC, the upgraded technology just put more of the substance into the sewage sludge that is disposed of by being applied as “fertilizer” on agricultural cropland.

Halden is planning to continue his research and study body burdens and health effects in pregnant women, nursing mothers and infants. Ecologically speaking, we are probably better off living with a few germs, and hand washing with regular soap has been shown to be just as effective as with antimicrobial soaps in sanitizing hands. Yet another good reason to reconsider our fear of germs - sometimes, it seems, the cure is worse than the disease.

No CommentsContinue Reading