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Concentration levels of 226Ra, 222Rn and 210Pb were analyzed in domestic bottled waters commercially available in Austria. Concentrations up to 0.23 Bq/l, with a geometric mean of 0.041 Bq/l were found for 226Ra. Concentrations for 222Rn ranged from <0.12–18 Bq/l, the geometric mean being 0.54 Bq/l. Lead-210 was analyzed in selected samples, the concentrations ranging from <2 to 34 mBq/l, with a geometric mean of 4.7 mBq/l. Ingestion doses resulting from consumption of these waters were calculated for the geometric mean and the maximum concentrations of the three radionuclides. The effective dose equivalents for different age groups of the population due to the intake of 226Ra range from 0.001 to 0.22 mSv/y and of 210Pb from 0.0003 to 0.05 mSv/y. Ingestion doses from 222Rn are low compared to those from 226Ra and 210Pb, ranging from 0.0001 to 0.011 mSv/y for adults and children, respectively. The doses are compared to the total ingestion dose from dietary intake of natural radionuclides on an annual basis. [Copyright &y& Elsevier]

The delineation of radon prone areas is one of the central requirements of the European Council Directive 2013/59/EURATOM. It is quite a complex task which usually requires the collection of radon data through an appropriate survey as a first step. This paper presents the design and methodology of the recent Austrian radon survey (ÖNRAP 2, 2013–2019) and its implementation. It details the results of the nationwide survey as well as correlations and dependencies with geology and building characteristics. The paper also discusses the representativeness of the survey as well as advantages and disadvantages of the selected approach. For the purpose of establishing a new delineation of radon prone areas in Austria we distributed approximately 75,000 passive long-term radon detectors. They were offered to selected members of the voluntary fire brigades and this resulted in about 50,000 radon measurements. Thus, a return rate of about 67% was achieved. The distribution of the radon results closely follows a log-normal distribution with a median of 99 Bq/m³, a geometric mean of 109 Bq/m³, and a geometric standard deviation factor of 2.29. 11% of the households show a mean radon concentration above the national reference level of 300 Bq/m³. Important data on building characteristics and the location of the measured rooms were collected by means of a specific questionnaire and a measurement protocol that were handed out together with the radon detectors. We were able to identify significant correlations between the indoor radon concentration and geology, the year of construction, and the coupling of the room to the ground (basement yes/no, floor level). Being a geographically-based and not a population-weighted survey, the comparison of building characteristics with the Austrian census data confirms that rural areas are over-represented in this survey. As a summary, the selected approach of conducting passive long-term radon measurements in selected dwellings of members of the voluntary fire brigades proved to be an efficient method to collect reliable data as a basis for the delineation of radon prone areas. The next step was to eliminate factors that influence the measured radon concentration through appropriate modelling. Based on the results predicted by the model radon areas are then be classified. This will be presented in a subsequent publication. • Extensive nationwide indoor radon survey with 50,000 radon measurements. • Collection of data on factors influencing the indoor radon level through a comprehensive questionnaire. • Establishment of a sound database as input for a model to delineate radon prone areas. [ABSTRACT FROM AUTHOR]

Abstract: The accumulation of natural and artificial radionuclides in humans and domestic animals is of interest in estimating effective doses of exposed humans and to decide whether animal products can be used for nutrition of the population. In this paper we present an investigation of the 137Cs- and 40K-activity levels of the ribs and sternum of a “mountain pasture” cow, born in a highly contaminated region of Styria, Austria, at the time of the radioactive fallout following the Chernobyl accident. This is the first systematic investigation of the variation in activity levels of a contaminated animal. The International Commission on Radiological Protection (ICRP) assumes that cesium and potassium are homogenously distributed throughout the whole body of an organism. However, the presented results show that there is a non-uniform distribution of 137Cs and 40K in different skeletal bones and their adherent tissues of a dairy cattle. We found that activity concentrations of 137Cs and 40K varied up to a factor 2.5 in different components of the ribs. The minimum values of 137Cs and 40K in the ribs were 29.9 and 21Bqkg−1 fresh mass for trabecular bone in the vertebral half of asternal ribs, and the maximum values 332 and 132Bqkg−1 fresh mass for a mixed sample composed of a cartilaginous tissue layer and parts of the perichondrium, both originating from asternal costal cartilages, respectively. [Copyright &y& Elsevier]

In general, indoor radon concentration is subject to seasonal variability. The reasons are to be found (1) in meteorological influence on the transport properties of soil, e.g. through temperature, frozen soil layers and soil water saturation; and (2) in living habits, e.g. the tendency to open windows in summer and keep them closed in winter, which in general leads to higher accumulation of geogenic Rn in closed rooms in winter. If one wants to standardize indoor Rn measurements originally performed at different times of the year, e.g. in order to make them comparable, some correction transform as a function of measurement time which accounts for these effects must be estimated. In this paper, the seasonality of indoor Rn concentration measured in Austria is investigated as a function of other factors that influence indoor Rn. Indoor radon concentration is clearly shown to have seasonal variability, with higher Rn levels in winter. However, it is complicated to quantify the effect because, as a consequence of the history of an Rn survey, the measurement season maybe correlated to geological regions, which may introduce a bias in the estimate of the seasonality amplitude. [Copyright &y& Elsevier]

Both global and Chernobyl fallout have resulted in environmental contamination with radionuclides such as 137Cs, 90Sr and 239+240Pu. In environmental samples, 137Cs and 239+240Pu can be divided into the contributions of either source, if also the isotopes 134Cs and 238Pu are measurable, based on the known isotopic ratios in global and Chernobyl fallout. No analogous method is available for 90Sr. The activity ratios of Sr to Cs and Pu, respectively, are known for the actual fallout mainly from air filter measurements; but due to the high mobility of Sr in the environment, compared to Cs and Pu, these ratios generally do not hold for the inventory many years after deposition.In this paper we suggest a method to identify the mean contributions of global and Chernobyl fallout to total Sr in soil, sediment and cryoconite samples from Alpine and pre-Alpine regions of Austria, based on a statistical evaluation of Sr/Cs/Pu radionuclide activity ratios. Results are given for Sr:Cs, Sr:Pu and Cs:Pu ratios. Comparison with fallout data shows a strong depletion of Sr against Cs and Pu. [Copyright &y& Elsevier]