Надеина Л.В. Радиоэкология

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4. Альфа-частицы действуют на организм на небольшом расстоянии от

источника (0,05 миллиметра) и приводят к гибели клеток, через которые

они проходят.

5. Вся их энергия полностью поглощается тканью в точечной области.

6. Поэтому в результате вдыхания этих частиц может появиться «дыра»

в легких.

7. Известно, что риск возникновения рака легких при ингалировании

нерастворимых

соединений плутония в 2-3 раза выше, чем от раствори-

мых, что можно интерпретировать как эффект «горячих частиц».

8. Наименьшая доза, при которой происходит канцерогенез, оценивает-

ся в 24000 Рад.

9. Сложность оценки поглощенных доз от «горячих частиц» для близ-

лежащих клеток состоит в том, что «горячие частицы» перемещаются.

10. Например, легочная ткань старается вытолкнуть

инородные части-

цы в горло, откуда они могут попасть в пищевод или лимфоузлы.

11. Клетки-макрофаги также перемещают частицы с места на место.

12. После аварии 06.04.1993 на радиохимическом производстве СХК в

районе следа было установлено присутствие большого количества час-

тиц микронного размера (10мкм) с мощностью дозы гамма-излучения

более 24мР/ч.

13. По своим параметрам эти образования являются классическими «го-

рячими частицами». Кроме бета-излучателей, в них находятся альфа-

излучатели, такие как уран-235, плутоний-239, америций-241 и т.д., что

может кратно увеличить данную расчетную дозу.

14. На сегодняшний день с помощью методики осколочной (f) радио-

графии достаточно четко откартирована зона максимального накопле-

ния микровключений

делящихся элементов, образующих многолучевые

“звезды» в верхнем горизонте почв.

15. Трагедия ликвидаторов последствий аварии на ЧАЭС заключается

не только в том, что они получили высокие дозовые нагрузки от внеш-

них факторов, а в том, что они подверглись массированному воздейст-

вию потока «горячих частиц».

16. Аналогичная ситуация может наблюдаться на урановорудных пред

приятиях. 17. В Томском регионе это один из возможных радиационно

опасных факторов, обусловливающих высокие дозовые нагрузки на ор-

ганизм человека, устанавливаемые методами биодозиметрии.

(Л.П. Рихванов «Радиоактивные элементы в окружающей среде и

проблемы радиоэкологии», Томск, 2009)

UNIT IV

Radioactive Contamination and Radiation Exposure

Warming-up

Radiation Control Technician (RCT )

☀ What does RCT do?

☀ What role do radioactive control technicians play in ensuring the

health and safety of employees working in radiation areas?

Picture 1

Picture 2

Uranium mining

Look at the pictures 1 and 2 and answer the questions.

☀ Do you know that uranium is the principle fuel for nuclear reactors and the

main raw material for fission nuclear weapons?

☀ Is uranium already radioactive when it is dug out of the ground?

☀What processes does uranium ore need to go through in order to concen-

trate the radioactivity by 2-3% to become nuclear reactor grade fuel, and by

80% to become weapons grade?

☀ Do you know in what countries over half of the world’s uranium is?

☀ Uranium is mined in 18 countries. Which ones?

☀ What is the most prevalent isotope in uranium ore which has a half-life of

about 4.5 billion years; that is, only half the atoms will decay in that amount

of time?

☀ Are uranium miners exposed to radioactive radon gas?

☀ Why does uranium mining require a great deal of water?

☀ Where is water which becomes radioactive waste placed?

☀Are evaporation ponds always adequately secured from leaking and flood-

ing?

☀Do you know that contaminated rainwater can enter the soil and, eventu-

ally, the food chain, endangering health?

Do you know that …?

Glowing trucks, mutated animals, black rain, and the ghost town «Pripyat».

Such haunting images are etched into the memories of Ukrainians who sur-

vived the 1986 nuclear explosion at the Chernobyl Atomic Energy Station.

Residents were exposed to an unprecedented amount of radioactive contami-

nation that posed serious consequences. Affecting individual health, the envi-

ronment, the economy and political relationships, daily life for these people

has been assaulted on multiple fronts. While some of the immediate dangers

have transitioned into painful memories, many residents continue to live on

contaminated land. Due to a lack of reliable information, many young fami-

lies are defenseless against the invisible dangers of radioactive contamination.

Chernobyl Matryoshka

The matryoshka doll (nesting Russian doll) is a well-known phenomenon. In

this particular example, the doll is used to make a statement about the radio-

active contamination from the Chernobyl disaster.

1. Read the text and do the tasks.

Radioactive Contamination and Radiation Exposure

Radioactive contamination and radiation exposure could occur if

radioactive materials are released into the environment as the result of an

accident, an event in nature, or an act of terrorism. Such a release could

expose people and contaminate their surroundings and personal property.

Radioactive contamination occurs when radioactive material is

deposited on or in an object or a person. Radioactive materials released into

the environment can cause air, water, surfaces, soil, plants, buildings, people,

or animals to become contaminated. A contaminated person has radioactive

materials on or inside their body.

External contamination occurs when radioactive material, in the form of

dust, powder, or liquid, comes into contact with a person's skin, hair, or

clothing. In other words, the contact is external to a person's body. People

who are externally contaminated can become internally contaminated if

radioactive material gets into their bodies.

Internal contamination occurs when people swallow or breathe in

radioactive materials, or when radioactive materials enter the body through

an open wound or are absorbed through the skin. Some types of radioactive

materials stay in the body and are deposited in different body organs. Other

types are eliminated from the body in blood, sweat, urine, and feces.

Radioactive materials give off a form of energy that travels in waves or

particles. This energy is called radiation. When a person is exposed to

radiation, the energy penetrates the body. For example, when a person has an

x-ray, he or she is exposed to radiation.

A person exposed to radiation is not necessarily contaminated with

radioactive material. A person who has been exposed to radiation has had

radioactive waves or particles penetrate the body, like having an x-ray. For a

person to be contaminated, radioactive material must be on or inside of his or

her body. A contaminated person is exposed to radiation released by the

radioactive material on or inside the body. An uncontaminated person can be

exposed by being too close to radioactive material or a contaminated person,

place, or thing.

Radioactive materials could be released into the environment in the

following ways:

① A nuclear power plant accident

② An atomic bomb explosion

③ An accidental release from a medical or industrial device

④ Nuclear weapons testing

⑤ An intentional release of radioactive material as an act of terrorism

People who are externally contaminated with radioactive material can

contaminate other people or surfaces that they touch. For example, people

who have radioactive dust on their clothing may spread the radioactive dust

when they sit in chairs or hug other people. People who are internally

contaminated can expose people near them to radiation from the radioactive

material inside their bodies. The body fluids (blood, sweat, urine) of an

internally contaminated person can contain radioactive materials. Coming in

contact with these body fluids can result in contamination and/or exposure.

People who are externally contaminated can spread the contamination

by touching surfaces, sitting in a chair, or even walking through a house.

Contaminants can easily fall from clothing and contaminate other surfaces.

Homes can also become contaminated with radioactive materials in body

fluids from internally contaminated people. Making sure that others do not

come in contact with body fluids from a contaminated person will help

prevent contamination of other people in the household.

Since radiation cannot be seen, smelled, felt, or tasted, people at the site

of an incident will not know whether radioactive materials were involved.

You can take the following steps to limit your contamination.

1. Get out of the immediate area quickly. Go inside the nearest safe

building or to an area to which you are directed by law enforcement or health

officials.

2. Remove the outer layer of your clothing. If radioactive material is on

your clothes, getting it away from you will reduce the external contamination

and decrease the risk of internal contamination. It will also reduce the length

of time that you are exposed to radiation.

3. If possible, place the clothing in a plastic bag or leave it in an out-of-

the-way area, such as the corner of a room. Keep people away from it to

reduce their exposure to radiation. Keep cuts and abrasions covered when

handling contaminated items to avoid getting radioactive material in them.

4. Wash all of the exposed parts of your body using lots of soap and

lukewarm water to remove contamination. This process is called

decontamination. Try to avoid spreading contamination to parts of the body

that may not be contaminated, such as areas that were clothed.

5. After authorities determine that internal contamination may have

occurred, you may be able to take medication to reduce the radioactive

material in your body.

2. Answer the questions.

1) What is radioactive contamination?

2) What is external contamination?

3) What is internal contamination?

4) What is radiation exposure?

5) How does contamination differ from exposure?

6) How can exposure or contamination happen?

7) How is radioactive contamination spread?

8) How could your home become contaminated?

9) How can you limit contamination?

Grammar in Use

Forms of Infinitive

Simple Continuous Perfect Perfect Continuous

Simultaneousness Priority

Active to contami-

nate

to be contami-

nating

to have

contaminated

to have been con-

taminating

Passive To be

contaminated

–––– To have been

contaminated

–––––

Complex Object

Noun (Common case) } + Infinitive

Pronoun (Objective case) } + Infinitive

Complex Subject

Subject + Predicate + Infinitive

Noun (Common case) (Passive Voice)

Pronoun (Nominative case) or

(Active Voice)

Note: Active Voice ⇦ to seem, to appear – казаться;

to prove, to turn out – оказаться; to happen, to chance – случайно оказаться

to be likely – вероятно; to be unlikely – маловероятно;

to be sure – несомненно; to be certain – обязательно

Infinitive

At the

beginning

of the

sentence

At the end

of the

sentence

After the

subject

After last,

first,

second

After the

predicate

Function

of the

subject

Function

of the ad-

verbial

modifier

Function

of the

attribute

Function

of the

attribute

Function

of the

object

Перевод:

существи-

тельным

или неоп-

ределен-

ной фор-

мой глаго-

ла

Перевод:

для + сущ.

или

чтобы +

неопреде-

ленная

форма

глагола

Перевод:

придаточ-

ным пред-

ложением:

который

может,

который

дет

Перевод:

кто (что)

и глагол

в том же

времени,

что и

глагол гл.

лож.

Перевод:

неопреде-

ленной

формой

глагола

2.1 Translate the following sentences paying attention to Subjective Infini-

tive Construction and Objective Infinitive Construction.

a) They enable scientists to measure extremely small amounts of chemical

elements and isotopes present in released radioactive materials, thereby pro-

viding information about the process which formed them.

b) All the sample’s activity was found to be contained in the separated 54 hot

particles.

c) The activity of the individual particles was estimated to be in the range 0.1

to 2.0 Bq of americium- 241 and the average diameter was about 20 mi-

crometers.

d) The safety trials were conducted to investigate the behaviour of the core of

nuclear devices under simulated faulty detonation conditions.

e) The activity of plutonium-239 was found to fall in the range 5 to 300 kBq,

although a particle with a level of about one MBq was also found.

f) In addition to plutonium, the particles were found to contain other elements.

g) In general, any facility for the processing of nuclear material is known to

release small, but detectable, amounts of radioactive and nonradioactive iso-

topes to the immediate environment.

2.2 Say what grammar the following sentences illustrate.

1. People who are externally contaminated can become internally

contaminated if radioactive material gets into their bodies.

2. Radioactive contamination and radiation exposure could occur if

radioactive materials are released into the environment as the result of an

accident, an event in nature, or an act of terrorism.

3. If radioactive material is on your clothes, getting it away from you

will reduce the external contamination and decrease the risk of internal

contamination.

4. Radioactive contamination occurs when radioactive material is

deposited on or in an object or a person.

5.When a person is exposed to radiation, the energy penetrates the body.

6. Making sure that others do not come in contact with body fluids from

a contaminated person will help prevent contamination of other people in the

household.