Radiation: the pros and cons

From uranium in Chernobyl to polonium in a sushi bar, radiation has a bad reputation. But that's not the whole story. Julia Stuart traces the radioactive elements that change our lives - for the better


Smoke detectors

Americium-241 is a very low-activity radioactive element that emits alpha particles, a low-energy form of radiation. As air passes across the americium source within the detector, the radiation ionises any smoke particles. This ionised air is then picked up by an electronic sensor, sounding the alarm.

Treating cancer

A range of radioactive elements are used in the fight against cancer. The key factor is to accurately target the cancer cells and destroy them, while as far as possible avoiding exposing the rest of the body to radiation. For example, samarium-153 is used to treat prostate cancer. A very high dose of radiation can be given to just the prostate gland by inserting little grains of radioactive material into it in a relatively simple operation, sometimes carried out under local anaesthetic. It exposes the rest of the body to only a very low dose of radiation.

Another common element used in cancer treatment is iodine-131, which is used to tackle cancers and other disorders of the thyroid - both the former US President George Bush and his wife were both treated for Grave's disease with radioactive iodine.

Medical diagnosis

Some radioactive elements can be used as "tracers" - they are injected into the bloodstream so that its flow can be tracked and the function of various organs monitored. For example, in Parkinson's disease, technetium-99m is injected and follows the dopamine pathway in the brain, so that doctors can determine whether it is working normally.

Similar techniques can be used to monitor blood flow to the heart. If there are any blockages inhibiting the flow, these can be detected before they cause a heart-attack.

Pain relief

It is typically very difficult to control the pain for patients who have tumours that have spread into bone tissue. But by using a radioactive material such as samarium-153 or strontium-89, high doses of radiotherapy can be delivered just to the bone tumours and relieve the pain. In trials, the treatment has been shown to be effective.

Food preservation

Passing food through a beam of gamma rays given off by the element cobalt-60 can extend the shelf life of meat, poultry, vegetables and fruit by inhibiting bacteria. It cannot be used on produce that has a high water content, because the food would explode. It was first used in spices, as they were kept for a long period of time between uses.

Appliance indicator lights

When you turn on an appliance, such as a coffee-maker or kettle, an electrical charge passes through the gas krypton-85. The current causes the gas to become active, ionising the air around it to produce the glow.

Dentistry

Uranium is not just for bombs and power stations. Uranium-238, the most common isotope of uranium found in nature, can be mixed in with the material that is used to make dentures to increase their strength. It is also used to help dentists try to match up the colour of the dentures to the real teeth that remain. The uranium in this case is not being used for its radioactivity - it has a half-life of 4.46 billion years, so it is safe.

Emergency management

When there have been suspected leaks at nuclear power stations, or when authorities suspect that a dirty bomb may have been used, they need be able to verify that their instruments are working correctly. A radioactive source, typically strontium-90, which emits gamma rays, is used.

Space satellites

Plutonium-238 is emits radioactive alpha particles, the type of radiation that can be stopped entirely by no more than a sheet of paper. As it decays, it gives off heat, and this heat is then used to generate electricity to power the satellite.

Power generation

Uranium-235 is the isotope of uranium widely used in nuclear power stations, which generate 20 per cent of the electricity used in Britain. When the atom breaks apart it gives off a huge amount of energy in the form of heat. The heat is transferred to water, and the resulting steam is used to run a turbine generator.

Fluorescent lights

Thorium-229 is a gas often used in lighting. As a small electric charge passes through a tube of the gas, it triggers the thorium to react and produce the light.

Anti-static agents

Polonium has no stable isotopes, but in a sealed and controlled form that reduces radiation hazards, the element is used to eliminate static charges - particularly in textile mills and on brushes used to remove dust from photographic film. The isotope polonium-210 represents a radiation hazard if it is taken into the body, by breathing it in, taking it into the mouth, or getting it into a wound.

PROMOTED VIDEO
News
ebooksNow available in paperback
Sport
Diego Costa, Ross Barkley, Arsene Wenger, Brendan Rodgers, Alan Pardew and Christian Eriksen
footballRodgers is right to be looking over his shoulder, while something must be done about diving
News
The illusionist believes hypnotism helped him to deal with the lack of control he felt growing up
people'It’s not that people react badly to it – they really don't care'
News
i100
Life and Style
tech
Life and Style
gaming
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Ampersand Consulting LLP: Network / Systems Administrator (LAN, WAN, Windows)

£38000 - £42000 per annum + Bonus and Benefits: Ampersand Consulting LLP: Netw...

Investigo: Group Financial Controller

£50000 - £55000 per annum: Investigo: A growing group of top end restaurants l...

Ashdown Group: HR Generalist - 2 week contract - £200pd - Immediate start

£200 per day: Ashdown Group: Working within a business that has a high number ...

Austen Lloyd: Private Client Solicitor - Oxford

Excellent Salary : Austen Lloyd: OXFORD - REGIONAL FIRM - An excellent opportu...

Day In a Page

In a world of Saudi bullying, right-wing Israeli ministers and the twilight of Obama, Iran is looking like a possible policeman of the Gulf

Iran is shifting from pariah to possible future policeman of the Gulf

Robert Fisk on our crisis with Iran
The young are the new poor: A third of young people pushed into poverty

The young are the new poor

Sharp increase in the number of under-25s living in poverty
Greens on the march: ‘We could be on the edge of something very big’

Greens on the march

‘We could be on the edge of something very big’
Revealed: the case against Bill Cosby - through the stories of his accusers

Revealed: the case against Bill Cosby

Through the stories of his accusers
Why are words like 'mongol' and 'mongoloid' still bandied about as insults?

The Meaning of Mongol

Why are the words 'mongol' and 'mongoloid' still bandied about as insults?
Mau Mau uprising: Kenyans still waiting for justice join class action over Britain's role in the emergency

Kenyans still waiting for justice over Mau Mau uprising

Thousands join class action over Britain's role in the emergency
Isis in Iraq: The trauma of the last six months has overwhelmed the remaining Christians in the country

The last Christians in Iraq

After 2,000 years, a community will try anything – including pretending to convert to Islam – to avoid losing everything, says Patrick Cockburn
Black Friday: Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Britain braced for Black Friday
Bill Cosby's persona goes from America's dad to date-rape drugs

From America's dad to date-rape drugs

Stories of Bill Cosby's alleged sexual assaults may have circulated widely in Hollywood, but they came as a shock to fans, says Rupert Cornwell
Clare Balding: 'Women's sport is kicking off at last'

Clare Balding: 'Women's sport is kicking off at last'

As fans flock to see England women's Wembley debut against Germany, the TV presenter on an exciting 'sea change'
Oh come, all ye multi-faithful: The Christmas jumper is in fashion, but should you wear your religion on your sleeve?

Oh come, all ye multi-faithful

The Christmas jumper is in fashion, but should you wear your religion on your sleeve?
Dr Charles Heatley: The GP off to do battle in the war against Ebola

The GP off to do battle in the war against Ebola

Dr Charles Heatley on joining the NHS volunteers' team bound for Sierra Leone
Flogging vlogging: First video bloggers conquered YouTube. Now they want us to buy their books

Flogging vlogging

First video bloggers conquered YouTube. Now they want us to buy their books
Saturday Night Live vs The Daily Show: US channels wage comedy star wars

Saturday Night Live vs The Daily Show

US channels wage comedy star wars
When is a wine made in Piedmont not a Piemonte wine? When EU rules make Italian vineyards invisible

When is a wine made in Piedmont not a Piemonte wine?

When EU rules make Italian vineyards invisible