Lesson four

1. Look through the list of English words and their Russian equivalents. You will need them for better understanding text C.

exposure – воздействие; inhalation - вдыхание;, ingestion - глотание; dermal кожа, кожный; nanotoxicology - нанотоксикология, nanostructure – наноструктура; nanodevice – наноустройство; assessment - оценка, учет; hazard угроза, опасность, опасный и вредный фактор; to alter - изменять; переделывать; adverse effect - вредное воздействие, неблагоприятное последствие; to investigate – исследовать, изучать; cell – клетка; to affect - действовать, влиять; to digest - усваиваться; to absorb – всасывать, впитывать, поглощать; carbon soot - угольная сажа; сажа; "grey goo" – серая слизь - гипотетический сценарий конца света, связанный с успехами молекулярных нанотехнологий и предсказывающий, что неуправляемые самореплицирующиеся нанороботы поглотят всю биомассу Земли, выполняя свою программу саморазмножения (данный сценарий известен под названием «экофагия»); nanobots - . "nanobot" and "nanorobot" usually mean the same thing; undetectable - неопределяемый, невыявленный, необнаруживаемый

Text C

I. Read the text looking for the information about adverse effects of engineered nanoparticles (NP).

Nanomaterials – Potential Risks for Human Health and the Environment

1. Exposures to airborne nano-sized particles (particles <100 nm) have been experienced by humans throughout their evolutionary stages. Most recently, the rapidly developing field of nanotechnology is likely to become yet another source for human exposures to nano-sized particles – engineered NP – by different routes, i.e., inhalation, ingestion, dermal or even injection.

2. An emerging discipline - nanotoxicology, which can be defined as safety evaluation of engineered nanostructures and nanodevices - is gaining increased attention. Nanotoxicology research will not only provide information for risk assessment of NP based on data for hazard identification, dose response relationships and biokinetics, but will also help to advance further the field of nanomedicine by providing information to alter undesirable NP properties.

3. Although potential adverse effects of engineered NP have not been systematically investigated, there are a number of studies in the area of inhalation toxicology and also human epidemiology from which some preliminary conclusions about effects of nano-sized particles can be drawn. There are also some decades-old – mostly forgotten – studies with nano-sized particles which shed light on the biokinetics of such particles once introduced into the organism.

4. Results so far demonstrate that the highly desirable properties of nanoparticles, which makes them attractive as medicinal aerosols, as well as their potential to induce toxicity, depend not only on their size but on a variety of surface properties. To establish the principles that govern interactions of nanomaterials with cells and the environment will be a major challenge for future research.

5. For the near-term, critics of nanotechnology point to the potential toxicity of new classes of nanosubstances that could adversely affect the stability of cell membranes or disturb the immune system when inhaled, digested or absorbed through the skin. Objective risk assessment can profit from the bulk of experience with long-known microscopic materials like carbon soot or asbestos fibres. Nanoparticles in the environment could potentially accumulate in the food chain.

6. An often cited worst-case scenario is "grey goo", a hypothetical substance into which the surface of the earth might be transformed by self-replicating nanobots running amok. This concept has been analyzed by Freitas in "Some Limits to Global Ecophagy by Biovorbus Nanoreplicators, with Public Policy Recommendations"

7. Societal risks from the use of nanotechnology have also been raised, such as hypothetical nanotech weapons (e.g., a nanomachine that consumed the rubber in tires would quickly disable many vehicles), and in the creation of undetectable surveillance capabilities.

Notes

1. "Some Limits to Global Ecophagy by Biovorbus Nanoreplicators, with Public Policy Recommendations" - «Пределы вызванной нанороботами экофагии».

II. Add to your list of words some new words with the prefix «nano-» from this text. Comment on them. Learn them.

III. Comment on the following statement:

Nanomaterials – the potential risks for human health and the environment.

IV. Answer the following questions:

1. What are the potential risks of nanomaterials for human health?

2. Which worries you more: potential benefits or potential risks of nanotechnology?

3. What is “grey goo”?

V. Summarize the general ideas developed in texts A, B and C. Use the following plan:

1. The opportunities of nanotechnology.

2. Anew generation of products.

3. Pros and cons of nanotechnology.

VI. Write a summary on the text.