Cancer in populations living in regions with radioecological problems in Bulgaria.
OBJECTIVE
To analyse the incidence and mortality of some malignant diseases among the population living in regions of past uranium extraction in Bulgaria.


METHODS
A retrospective study on cancer incidence and mortality in the population living around two regions with radioecological problems was conducted. According to the expected individual annual effective doses for the population, regions with expected highest radiation risk (average effective dose > 10 mSv per year) were the villages Yana, Eleshnitza and Seslavtzi (group A), and with expected relatively high radiation risk (average effective dose > 5 mSv per year) were the town of Buhovo, and the villages Dolni Bogrov and Gorni Bogrov (group B). The ecologically clean village German was chosen as a control settlement. The incidence and mortality of gastrointestinal tract cancers, bronchus and lung cancer, breast cancer, thyroid cancer, and myeloid leukaemia for the period 1995- 2001 were studied.


RESULTS
The incidence of the gastrointestinal tract cancers in the population of German was significantly lower than those for Bulgaria and for group B. The mortality from this disease of groups A, B and Bulgaria were significantly higher than in the control settlement. Standardized mortality of lung cancer in the population of the villages with highest and relatively high radiation risk was significantly higher than in German and Bulgaria.


CONCLUSIONS
The incidence and mortality changes of diseases studied are a consequence of the impact of many factors. Moreover, they do not characterize the impact of the radiation factor.
Chobanova
N
N
Radiation Epidemiology Laboratory, National Center of Radiobiology and Radiation Protection, Sofia, Bulgaria.
Genchev
G
G
Yagova
A
A
Georgieva
L
L