LOS ANGELES, Feb. 17 (Xinhua) -- Nanoscientists should try to ensure that their breakthrough materials should not have toxic effects, experts said.
Nanotechnology must not join DDT, ozone-eating refrigerants and other "wonderful technologies" whose toxic effects have surpassed their usefulness, Vicki Colvin, a nanotechnology researcher at the Rice University, told the annual meeting of the American Association for the Advancement of Science (AAAS).
The unique properties that make nanomaterials potentially useful in applications from sunscreen to fuel storage are the same properties that may pose environmental and health risks, Colvin said in a lecture at the meeting, which opened in San Francisco on Thursday.
Colvin said that in order to avoid potential risks, scientists should fully understand these properties of nanomaterials.
"We can do something pretty unique, which is from the beginning, engineer our materials as safe materials or begin to understand how that might happen," she said.
The materials in question are built from vanishingly small particles, on the scale of a billionth of a meter, with average sizes about the width of the period at the end of this sentence.
But their impressively small size is only one of their unique features, Colvin said, noting that their surface area and even basic chemical properties differ from their bulk material counterparts.
"All of the fantastic and unusual properties of these materials are at the heart of their use in technology," Colvin explained.
She said nanoparticles can be inhaled and probably absorbed through the skin as well, potentially causing immune reactions.
Several experiments with rats suggest that particles smaller than 100 nanometers, if inhaled, can make their way into the brain and central nervous system, according to Colvin.
"Once they (the nanoparticles) are in contact with the body, they are processed through routes that your might expect many foreign objects to get processed, and the rules on that are something that we're just now examining," Colvin said.
Colvin called for strict regulation of existing nanomaterials, including clear labeling, saying "safety by design" could bring better products to market in the future.
For today's nanoengineers, she said, "integrating and thinking about issues of safety and sustainability as early as possible is really critical."
The five-day gathering is drawing up to 10,000 total attendees from around the world to explore "Science and Technology for Sustainable Well-Being", which is the theme of the event.