Analysis of 226Ra content and 222Rn exhalation rates in soil samples from Wukro, Tigray, using SSNTDs
Data files
Feb 18, 2025 version files 12.87 KB
-
README.md
4.30 KB
-
Wukro_Soil_Radium_Radon_Data.xlsx
8.57 KB
Abstract
Background: Radon gas, a decay product of radium, poses potential health risks due to its radioactive properties. Understanding radium content and radon exhalation rates in soil is essential for assessing environmental safety and radiological hazards.
Materials and Methods: Soil samples were collected from various locations in Wukro, Tigray, and analyzed using LR-115 type-II plastic film track detectors. Measurements included radium concentration, mass exhalation rates, and surface exhalation rates.
Results and Discussion: The radon mass exhalation rates ranged from 0.18 × 10⁻⁷ Bq.kg⁻¹.d⁻¹ to 0.82 × 10⁻⁷ Bq.kg⁻¹.d⁻¹, with a mean of 0.48 × 10⁻⁷ Bq.kg⁻¹.d⁻¹. Surface exhalation rates varied from 0.38 × 10⁻⁶ Bq.m⁻².d⁻¹ to 1.72 × 10⁻⁶ Bq.m⁻².d⁻¹, averaging 1.02 × 10⁻⁶ Bq.m⁻².d⁻¹. Radium concentrations ranged from 0.33 to 1.47 Bq.kg⁻¹, with an average of 0.87 Bq.kg⁻¹. A significant positive correlation between radium content and radon exhalation rates was observed, indicating a direct relationship between these variables. Clay soils exhibited the highest radium concentrations, while sandy soils had the lowest. All measured values were below the safety limit of 370 Bq.kg⁻¹ recommended by OECD and UNSCEAR, suggesting no significant radiological risk in the study area.
Conclusion: This study highlights the importance of monitoring natural radiation levels for environmental safety. The findings provide a baseline for future studies and emphasize the need for continuous assessment to detect any long-term changes in soil radioactivity.
https://doi.org/10.5061/dryad.n8pk0p35z
Description of the data and file structure
Data Description
This dataset contains measurements of radium concentrations (²²⁶Ra) and radon exhalation rates (²²²Rn) in soil samples collected from Wukro, Tigray, Ethiopia. The experimental study aimed to assess the radiological safety of soils by evaluating radium content and radon exhalation rates, using solid-state nuclear track detectors (SSNTDs), specifically LR-115 Type-II plastic detectors.
Experimental Efforts:
- Sample Collection: 12 soil samples were collected from various locations in Wukro town, categorized into clay, silt, and sand types.
- Sample Preparation: Soil samples were ground, sieved, and sealed in airtight containers for 4 months to allow equilibrium between radium and radon.
- Radon Detection: LR-115 detectors were exposed to radon emissions and later chemically etched to reveal alpha tracks, which were counted using an optical microscope.
- Data Analysis: Radium concentrations and radon exhalation rates were calculated based on observed track densities and established mathematical models.
Parameters Measured:
- Corrected Track Density (tracks.cm⁻²)
- Radium Content (Bq.kg⁻¹)
- Mass Exhalation Rates (Bq.kg⁻¹.d⁻¹)
- Surface Exhalation Rates (Bq.m⁻².d⁻¹)
- Alpha Index (Iα)
Applications:
The data support radiological hazard assessments and provide baseline information for monitoring environmental safety in areas with naturally occurring radioactive materials (NORMs).
Files and variables
File: Wukro_Soil_Radium_Radon_Data.xlsx
Description:
Variables
File Description:
This Excel file contains data collected from soil samples analyzed for ²²⁶Ra concentrations and ²²²Rn exhalation rates in Wukro, Tigray, Ethiopia.
Sheet 1: Soil Data
| Variable Name | Description | Units | Abbreviation |
|---|---|---|---|
| Sample Code | Unique identifier for each soil sample. | - | - |
| Soil Type | Classification of soil samples (Clay, Silt, Sand). | - | - |
| Track Density (tracks.cm⁻²) | Corrected track density observed on LR-115 detectors. | tracks.cm⁻² | - |
| Radium Content (Bq.kg⁻¹) | Effective radium concentration in each soil sample. | Bq.kg⁻¹ | Ra |
| Mass Exhalation (Bq.kg⁻¹.d⁻¹) ×10⁻⁷ | Radon exhalation rate per unit mass of soil. | Bq.kg⁻¹.d⁻¹ ×10⁻⁷ | Ex(M) |
| Surface Exhalation (Bq.m⁻².d⁻¹) ×10⁻⁶ | Radon exhalation rate per unit surface area of soil. | Bq.m⁻².d⁻¹ ×10⁻⁶ | Ex(S) |
| Alpha Index (Iα) | Dimensionless index indicating radiological risk from radon emissions. | - | Iα |
Missing Values:
- Missing data, if any, are indicated by blank cells.
Code/software
Software Requirements:
- Microsoft Excel (Version 2010 or later) – To view and analyze the Wukro_Soil_Radium_Radon_Data.xlsx file.
Workflow Description:
- Data Organization:
- Data was structured into columns and rows based on sample measurements.
- Calculations:
- Track densities were analyzed to compute radium content and radon exhalation rates using pre-defined formulas.
- Export Format:
- Data was saved in Excel (.xlsx) format to maintain compatibility with common software.
Scripts/Code Files:
- No custom scripts or code files were included in the dataset submission.
In this study, twelve soil samples were collected from various locations of the study area by grab sampling method. Sealed Can technique has been used. Following collection, collected soil samples were crushed into fine powder to ensure uniformity and consistency. Obtained soils were then sieved using a 200 micron-mesh size. For each measurement, 200 grams of fine powder was placed at the base of a cylindrical can with dimensions of 8 cm x 12 cm and sealed tightly and stored for duration of four months in order to reach equilibrium with its decay product. A piece of LR-115 Type-II plastic track detector, measuring 2 cm × 3 cm, was affixed to the inner surface of the cylindrical can, approximately 0.65 meters away from the surface of the samples. After exposure time of 4 months, the LR-115 detectors were removed and chemically etched in a solution of 2.5N NaOH at a temperature of 70°C for one hour and half. After this chemical treatment, the detector tracks which represent interactions between alpha particles and the detector surface were then counted using an optical microscope at a magnification of 400x.