Gross Alpha and Gross Beta Activity Concentrations in the Dust Fractions of Urban Surface-Deposited Sediment in Russian Cities

Studies of gross alpha and gross beta activity in road- and surface-deposited sediments were conducted in three Russian cities in different geographical zones. To perform radiation measurements, new methods were applied which allow dealing with low mass and low volume dust-sized (2–100 μm) samples obtained after the size fractionation procedure. The 2–10 μm fraction size had the highest gross beta activity concentration (GB)—1.32 Bq/g in Nizhny Novgorod and Rostov-On-Don, while the 50–100 μm fraction size was most prominent in Ekaterinburg. This can be attributed to the presence of radionuclides that are transferred through natural and anthropogenic processes. The highest gross alpha activity concentration (GA) in fraction sizes was found in Rostov-on-Don city within the 50–100 μm range—0.22 Bq/g. The fraction sizes 50–100 μm have a higher gross alpha activity concentration than 2–10 μm and 10–50 μm fraction sizes due to natural partitioning of the main minerals constituting the urban surface-deposited sediment (USDS). Observed dependencies reflect the geochemical processes which take place during the formation and transport of urban surface sediments. Developed experimental methods of radiation measurements formed the methodological base of urban geochemical studies.

Gross Alpha and Gross Beta Activity Concentrations in Dust Fraction of Urban Surface Deposited Sediment in Russian Cities

Study of gross alpha (GA) and gross beta (GB) activity in road and surface deposited sediments were performed in various geographical areas in three Russian cities. To perform radiation measurements, new methods were applied which allow dealing with low mass and low volume dust size (2-100μm) samples obtained after the size fractionation procedure. The 2-10 μm fraction size has the highest gross beta activity concentration (GB)– 1.32Bq/g in Nizhny Novgorod (NN) and Rostov-On-Don (RND) while the 50-100 μm fraction size in Ekaterinburg. This is maybe associated with the subsistence of radionuclides that conveyed through natural processes and anthropogenic applications. The highest gross alpha activity concentration (GA) in fraction sizes was found in Rostov-on-Don city within the 50-100 μm– 0.22Bq/g. The fraction size 50-100 μmhas a higher gross alpha activity concentration than 2-10 and 10-50 μmfraction sizes due to natural partitioning of the main minerals constituting the urban surface deposited sediment (USDS). The geochemical processes that occur during the formation and transportation of USDS are reflected in the observed dependencies.Developed experimental methods of radiation measurements allowed to the extent the methodological base of urban geochemical studies.

Determination of Gross Alpha and Gross Beta Activity Concentration in Bahe River Water Samples Within Xi'an Chanba Area

As a screening procedure, gross alpha and gross beta activity have been developed to determine whether further analysis of water samples related to specific radionuclide is necessary. In China, the determination of gross alpha and gross beta in drinking water was generally based on the HJ standard method: HJ 898-2017, water quality — determination of gross alpha activity — thick source method, and HJ 899-2017, water quality — determination of gross beta activity — thick source method. In this study, 15 water samples from Bahe river in Chan Ba region of Xi’an in China, were pretreated and analyzed by BH1216-III low background alpha and beta scintillation counter. The water samples were collected nearby residential area, wetland park, water conservation district and urban sewage treatment plant as well as other important locations which probably influence on the radioactivity level. The values of the activity concentrations of the gross alpha and beta measured in the water samples ranged from less than LD to 0.183Bq/L with a mean of 0.077Bq/L and 0.073–0.151Bq/L with a mean 0.102Bq/L respectively. All values of samples were lower than the limit level of 0.500Bq/L for gross alpha and 1.000Bq/L for gross beta, indicating that the radioactivity level in Bahe water between Chan Ba region of Xi’an is basically within the normal environmental background.

Radiological Status of Drinking Water Sources Around a Coal Mining Site in Kogi State, North Central Nigeria

The radioactivity of drinking water sources around Okaba coal mining area in Ankpa local government area of Kogi state, North central Nigeria have been carried out using a low background Gasless Alpha- Beta Counting System (Protean Instrument Corporation) – MPC 2000DP. The gross alpha and gross beta activity of water samples from four (4) sources (river/stream, borehole, sachet water and rain water) was measured. The grossalphaand gross-beta activity concentrations recorded were below the safe limits of 0.5 Bq/l and 1 Bq/l respectively, as recommended by the world health organization (WHO, 2017). Also, results of the committed effective dose (for adult and infant) calculated were all below the reference dose level (RDL) of 0.1mSv/yr (WHO, 2017) except for BW3 whose adult dose was above the RDL. Therefore, there is no immediate risk of internal radiation exposure to the populace via intake of water from the four major sources of drinking water around Okaba coal mining area. However, caution should be taken especially with regards long-term consumption of the ground water (BW3). Keywords: Okaba, radioactivity, gross-alpha, gross-beta, coal, water

Screening Level of Gross Alpha and Beta Activities in Building Materials

The objective of the present study is the screening of the gross alpha and gross beta activity of some building materials commercialized in Saudi Arabia. The measurements were carried out using a gas flow proportional counter. The study has shown that the gross alpha activity ranged between 0.21 and 8.27 Bq/kg with an average activity of about 1.96 Bq/kg, whereas the gross beta activity ranged between 6.47 and 276.47 Bq/kg with an average activity of about 65.27 Bq/kg. The obtained values of gross alpha and beta activities are in the worldwide range and no significant activity was observed that accentuate the attention, which show that no radiation risks come from these building materials and, therefore, from their origin areas.