Intended for healthcare professionals

Rapid response to:

Letters

Time for a smoke? One cigarette reduces your life by 11 minutes

BMJ 2000; 320 doi: https://doi.org/10.1136/bmj.320.7226.53 (Published 01 January 2000) Cite this as: BMJ 2000;320:53

Rapid Response:

Radioactivity in cigarettes

Drs Shaw, Mitchell and Dorling attempt to provide a simple but
"frightening statistic" to convince smokers to kick the "antisocial" habit
and throw the "cancer stick" to the nearest dustbin. In 1987, I wrote an
article titled "Radioactivity in tobacco'. Since anything "radioactive"
gets top billing in the press, the item was picked up by a national news
agency. Extensive coverage in several dailies must have hopefully
dissuaded a few from smoking. There were several anxious responses to the
news story.

Tobacco contains Polonium-210 and lead-210. These are decay products
of radon formed from radium present in the soil and are deposited on
tobacco leaves.Polonium and lead are volatalized due to cumbustion of
tobacco. About 20% of polonium and 10% of lead enter the lung through the
main smoke stream.

The lungs of smokers contain three times more polonium-210 and 1.5
time more lead-210 than those of nonsmokers.The daily radiation dose to
the lung of a person smoking 20 cigarettes per day is about 2400
microsievert.The dose rate depends on the radioactive content of the
tobacco, puff size,puff frequency and number of cigarettes smoked per
day.The annual radiation dose is 40 times the dose limit to radiation
workers.According to one report the polonium content in Indian tobacco is
10-15 times lower than that in US tobacco samples.(I am against the use of
all tobacco!!)

A 20 cigarettes per day smoker inhales atleast one kG of smoke
annually.Trace amounts of radioactivity may not be a major factor in
causing lung cancer as it is only one among the 3000 chemicals which have
been identified and quantified in tobacco smoke. Let us hope that
Dr.Dorling may be terrified by the thought of radioactive fumes from
cigarettes and may quit smoking for ever!

Competing interests: No competing interests

01 January 2000
K S Parthasarathy
Scientific Officer (H)
Atomic Energy Regulatory Board,Bombay