Indoor radon concentrations in kindergartens in three Bulgarian districts.

This article examines the results of a study of radon concentrations in kindergartens in three districts of north-western Bulgaria. For the period from December 2019 to May 2020, passive radon measurements were accomplished in 1490 premises of 130 kindergartens. The highest arithmetic mean (AM) value of 219 Bq m and geometric mean (GM) value of 156 Bq m radon concentration were found in the state kindergartens of the Vratsa district.

Indoor radon concentration in state schools of four Bulgarian districts.

Indoor radon concentrations were surveyed in 230 public schools in four Bulgarian districts for the period November/December 2019 to May/June 2020. The measurements were carried out in 2427 rooms on the basement, ground floor and first floor using the passive track detectors of the Radosys system. The estimated arithmetic and geometric means with standard deviations were 153 ± 154 and 114 Bq/m3 (geometric standard deviation (GSD) = 2.

Analysis of exposure to radon in Bulgarian rehabilitation hospitals.

Mineral springs are used in spa resorts throughout the world. Radon is a natural radioactive source, which can dissolve, accumulate, and be transported by water. This study investigates the radon concentration in air and water in 12 Bulgarian rehabilitation hospitals and presents the assessment of the exposure to radon in them.

Analysis of the spatial variation of indoor radon concentrations (national survey in Bulgaria).

This paper presents the methodology and results of the national radon survey in Bulgaria and its spatial variability. The measurements were carried out in 2778 dwellings using CR-39 track detectors over two successive 9 and 3-month periods from April 2015 to March 2016. The arithmetic (AM) and geometric (GM) means of annual indoor radon concentration were 111 ± 105 Bq/m and 81 Bq/m (GSD = 2.

BRONCHUS AND LUNG CANCER INCIDENCE IN POPULATION LIVING AROUND THE FORMER URANIUM MAINING AND MILING SITES.

The indoor radon concentrations and lung cancer incidence in Eleshnitza village and Blagoevgrad district of Bulgaria were examined in the study reported here. The Eleshnitza was the second largest uranium mining and milling region of the country. The geometric mean of indoor radon concentration in Eleshnitza (465 Bq/m3) was higher than the geometric mean of Blagoevgrad district (78 Bq/m3).