Radioactive Aerosols - Aerosols: Measurement, Dosimetry, and Health Effects - page 409

15.10.3.2 Lung Sickness Data
Lung cancer mortality represents a long-time effect of the irradiation of miners. The study of this
effect presents many dificulties in terms of collecting information during a long period of time,
when professional itinerary, working conditions, and other factors can change substantially.
On the other hand, both from the medical and economical point of view, it is important to assess
the effect of radon progeny on sickness rate disability as a short-time effect.
For this purpose, a comparative study was provided in the mining department of Karamazar,
Tadjikistan (Alterman, 1974), by studying the radon decay products concentration with a parallel
observation of the sickness rate disability of miners. The study was carried out in two steps. In the
irst period (1963-1965) and in the second (1967-1971), measures were taken to reduce the concen-
tration of radon decay products mainly by improving the eficiency of the ventilation system.
These results suggest that due to measures provided at the end of the irst period, the radon decay
product concentration was reduced:

• In all working sites, 4-9 times

• In drilling sites, 6.6-13 times

• Including 4-12 times in passing sites

Results with the maximum concentration decreased even more sharply: in all working sites 8-32,
in drilling 14-43, and in passing 10-60 times. Similar data on aerosol concentration suggested that
from period 1 to 2, a reduction in aerosol concentration took place on an average of 2.3 and 5 times
in terms of the maximum and was very close to the level of a limit dust permissible concentration of
2 mg/m 3 . Data in Figure 15.2 suggest that sickness of breathing organs in terms of days of disability for

Breathing organs sickness of miners

50

45

40 A1

A2
A3
A4
B1
B2
B3
B4
C1
C2
C3
C4

35

30

25

20

15

10

5

0

FIGURE 15.2 Sickness of different groups of miners in terms of the days of disability for two periods of
observation with the higher and lower concentration.1, high exposure (radon decay product concentration),
general number of days of sickness; 2, low exposure (radon decay product concentration), general number of
days of sickness; 3, high exposure, days in a hospital; A, for all miners; B, for drillers; C, for others.