AW: [ RadSafe ] Radon Breath Analysis - A very practical method

[ksparth at vsnl.com]

Breath analysis to detect and measure radon-222 to arrive at body burden due to radium was used for many years.I think the fraction of radon-222 exhaled through breath was taken as 0.45.You may come across several papers on the topic.

I have used the method to verify whether a person who did something terrible had ingested radium or not! Hold your breath! you may not believe what I am going to say!.A physician (a radiation oncologist, well known in India) asked one of his subordinates to remove some radium tubes which remained stuck up in an alluminium applicator. Total quantity was 50mg.The applicator was "loaded"  several years ago.It was used for many years as an intrauterine device to treat cancer.The worker  took the applicator to the hospital workshop. He tried hard to prise the source out but failed. he took a saw and slowly cut the applicator into two. He cut through one of the radium tubes.None noticed the damage till they received a telegram from the scientists of the Bhabha Atomic Research Centre(BARC) that some personnel monitoring film badges from the hosptials have patterns typical of high radiactive contamination.

I was then at BARC.We rushed to the hospital. Never in our history we were involved in such a massive decontamination effort.WE had to carry a truckfull of contaminated stuff in huge containers to Trombay for safe disposal.It took several days to decontaminate the site.Fortunately we had the necessay protective gear including masks.

The man who cut the source was invited to Mumbai. I collected his breath and measured the radon-222 levels using an electrostastic method to collect Polonium 214 from the breath sample and measuring the activity by the help of a scintillation counter. His body burden was modest at 0.3 microgm. We measured his body burden using whole-body radioactivity monitors.

Breath analysis requires extreme care. There are ways to circumvent interference due to atmospheric radon.

Regards

K.S.Parthasarathy