For a cautionary example of the paradox of innovation, look no further than asbestos, says Pratim Biswas, Ph.D. Asbestos—because of its unmatched strength, durability, and heat resistance—was long favored by the construction industry in a wide range of uses, including insulation, ceiling tile, and spray-on fireproofing. Yet today, the most dangerous asbestos fibers, if ingested or inhaled, are known to cause cancer of the lungs, chest, and abdominal linings. And symptoms may not become evident until many years after exposure.
“Here was a product that for many years was very effective, and now it's banned because of the harmful effects of its airborne microfibers,” says Dr. Biswas, the Stifel and Quinette Jens Professor of Environmental Engineering Science at Washington University in St. Louis.
Dr. Biswas sees asbestos as an analogy for the potential implications of manipulating even tinier particles at the atomic level—specifically, particles with a diameter of 10–100 nanometers, or about one-one thousandth the width of a human hair. With applications in solar power generators, electronic circuit elements, lasers, and numerous other devices, nanoparticles are the building blocks for nanostructured materials; when fused together, the properties of these compounds are far superior to those made from conventional materials. Yet, questions remain about the chemical structure of nanoparticles over time.
Studies have shown that nanoparticles contribute to, and may even accelerate, adverse effects on the environment, public health, and quality of daily life. “There is the concern that these nanoparticles, or building blocks, pose hazards in the form of wastes, or occupational hazards during manufacture,” says Biswas. “In the same way as asbestos, we don't want to learn in 10 years that these nanoparticles are harmful.”
In light of this issue, Dr. Biswas will present a timely overview of “Nanoparticles and the Environment” at the 2005 Critical Review. Dr. Biswas will be joined in the presentation by Chang-Yu Wu, Ph.D., Associate Professor of Environmental Engineering at the University of Florida. As both a tutorial and critical review of nanotechnology, Drs. Biswas and Wu will discuss:
An overview of nanotechnology, it's role in the economy, and how nanoparticles are “building blocks”;
Sources of nanoparticles—ranging from industrial emissions to atmospheric formation and conversion to occupational settings—and engineered nanoparticle production methodologies;
Measuring nanoparticles and the efficiency of capturing them in current particle control devices;
Use of nanoparticles in environmental technologies and implications for the energy sector;
Environmental impacts and potential health effects of nanoparticles; and
Recommendations for future research and regulation.
Dr. Biswas' research has contributed to the reduction of environmentally harmful submicrometer and ultrafine particles in aerosols. He also has pioneered processes for removing pollutants like heavy metals (e.g., lead and mercury) from coal combustion exhausts.
Dr. Biswas is confident that similar advances can be made to ensure that nanotechnology lives up to the promise of its novel applications, resulting in more breakthroughs. “Nanoparticles can be made safe,” he says. “They can be engineered to be safe. But it must be done from the start.”
The 2005 Critical Review will be published in the June issue of the Journal of the Air & Waste Management Association and presented on Wednesday, June 22, 8:30 a.m.–12:00 p.m., as part of A&WMA's 98th Annual Conference & Exhibition in Minneapolis, MN . For more information on the Critical Review and the Annual Conference, visit and bookmark www.awma.org/ace2005 , or call A&WMA Member Services at 1-412-232-3444 or 1-800-270-3444.