揽瓜阁阅读做题小分队第118天纳米技术 - ChaseDream

Nanotechnology -- the use of structures that have unusual properties because of their atomically tiny size – is already in use in more than 300 consumer products, from computers to cosmetics, but like atomic power itself, this new technology holds great promise as well as alarming possibilities. Determining the safety level of products that utilize nanotechnology is the daunting task of the Environmental Protection Agency (EPA). One reason that regulating nanotech products is so challenging is that nanoparticles, though they consist of the same chemicals as traditional products, have physical structures that give them very different properties, and they can enter the body by means other than those used by other small particles.

The actual method by which nanoparticles are created is relevant as well. For example, carbon can be used to create fullerenes, but there is more than one way to manufacture these nanoparticles, and each way leads to a fullerene with different characteristics. \ Because of this, some research has identified fullerenes as anti-oxidants, which are useful for treating cells by neutralizing free radicals, while other research shows fullerenes to be oxidants, which can damage cell membranes. Similarly, nanoparticles show great potential in cleaning up environmental contaminants, but these particles themselves might become nearly intractable long-term pollutants.

Some recent research has been truly alarming. Carbon nanotubes placed directly into the lungs of mice stimulated an immune response that left scar tissue. A similar experiment with a single-walled carbon nanotube soot mixture caused granulomas and lesions in the rats’ lungs, and proved fatal for 15% of the rats. (It should be noted that these experiments involved instilling the nanomaterials into the lungs; more experiments are needed involving inhalation.) Another consideration is that when studying the effects of nanomaterials, more than with typical chemicals, it is not enough to study a nanoparticle in a vacuum; all physical and chemical characteristics have to be microanalyzed by studying a material’s reactivity, solubility, and biological persistence under real world conditions.

Because the costs and benefits of nanotech research are so high, international cooperation among governments and businesses is essential to success. Currently, the U.S. is underfunding research in this field, and this could have calamitous results. The Toxic Substances Control Act is insufficient for covering many of the dangers unique to nanotech materials. Furthermore, not all nations have even created a set of regulations for nanotechnology, also a serious mistake. A product that reaches the market before it has been thoroughly understood could prove harmful to individual users and whole populations that have had only minimal exposure. This could so turn public opinion against nanotechnology that its tantalizing benefits would be indefinitely postponed.

1) Which of the following can be inferred from the passage regarding recent research on nanoparticles?
A) It has been done mostly in a vacuum without consideration for what happens under real world conditions.
B) Further experiments are required to adequately judge particular risks that have been identified.
C) It has been too narrowly focused on older nanoparticles, rather than the newer nanoparticles that will be used in the future.
D) It has created a generally negative sentiment in the general public regarding nanoparticles.
E) It has shown that carbon nanotubes are particularly dangerous in comparison to other types of nanoparticles.