ESTIMATION OF THE EQUIVALENT AND EFFECTIVE DOSE OF RADON FROM THE INGESTION OF WATER FROM DJIRI RIVER BY THE POPULATION, BRAZZAVILLE, REPUBLIC OF CONGO
Aug 2026· Carpathian Journal of Earth and Environmental Sciences· 0 citations
Abstract
This study aimed to measure radon concentration in Djiri River water and to evaluate the associated equivalent doses, effective doses, and lifetime cancer mortality risks for the population of Brazzaville, Republic of Congo. Radon concentration was measured in 29 water samples collected from the Djiri River using an AlphaGUARD PQ2000 PRO radon detector. Polyethylene terephthalate (PET) bottles were evaluated for sample storage in order to estimate radon losses during storage. To enable a direct comparison with the National Research Council (1999) reference values, the estimated cancer mortality risks were normalized to the same reference radon concentration. Measured radon concentrations ranged from 0.23 to 0.73 Bq/L, with a mean value of 0.425±0.12 Bq/L (equivalent to 425±120 Bq/m³). These concentrations are low and indicate that radiation exposure through drinking water ingestion is minimal under the investigated conditions. The estimated annual effective doses from water ingestion were 5.37×10⁻6 mSv/year for infants, 4.45×10⁻3 mSv/year for 1-year-old children, 2.03×10⁻3 mSv/year for 5-year-old children, 1.18×10⁻3 mSv/year for 10-year-old children, 4.38×10⁻6 mSv/year for 15-year-old children, and 4.02×10⁻3 mSv/year for adults. All estimated doses remained well below the World Health Organization guideline value of 0.1 mSv/year for drinking water. The estimated lifetime cancer mortality risks for males, females, and the total population were 6.35×10⁻7, 9.45×10⁻7, and 7.68×10⁻7, respectively. After normalization to the same radon concentration, these estimates were consistent with the projections reported by the National Research Council (1999). Although the estimated doses and risks are very low and do not indicate a significant radiological health concern, the results support periodic monitoring of radon in the Djiri River as part of routine environmental and public health surveillance.
Objectives of this study were to determine radon concentration in tap water and assess the annual effective dose (AED) and excess lifetime cancer risk (ELCR) associated with radon exposure in tap water in Chiang Khan District, Loei Province, Thailand. A total of 40 water samples were collected to determine radon concentration using the RAD7 radon detector and analyze the physical and chemical properties of the water using a multiparameter water quality meter. The results showed that radon concentrations in tap water were between 0.007 and 1.973 Bq/L with an average of 0.099 ± 0.307 Bq/L. The highest concentration was observed at one sampling location (1.973 Bq/L), although all measured values remained considerably below the World Health Organization (WHO) and U.S. Environmental Protection Agency (USEPA) recommended limits of radon levels in tap water. Radon concentration has a negative correlation with temperature. The AED and ELCR assessments showed that the infant group (0-1 years) had the highest risk compared to the children and adult groups due to the higher rate of water consumption per body mass. However, AED and ELCR values for all age groups were still low and did not exceed the levels that pose radiation risks to public health. This study provides the first baseline data on radon levels, associated radiological risks, and water quality parameters in tap water from Chiang Khan District, Loei Province.
Ing-orn Sittitanadol, K. Prakhammin, V. Atyotha· Sains Malaysiana· 0 citations
This study investigates the concentration of Rn-222 in domestic water sources within Nasarawa metropolis, Nasarawa State, Nigeria. With the aim of accessing the potential health concerns related to radon accumulation. A total of thirty water samples comprising ten each from wells, boreholes, and streams were collected and analyzed using a liquid scintillation counter (Tri-Carb LSA 1000). Key parameters evaluated include Rn-222 activity concentration, annual effective dose from ingestion and inhalation, dose contributions to the stomach and lungs, and the excess lifetime cancer risk. Measured Rn-222 levels ranged from 0.06 to 18.50 counts per minute (cpm), with a background radiation count of 63.83 cpm attributed to environmental and non-sample sources. Radon activity concentrations spanned from 3.14 × 100 to 1.15 × 103 Bq/L, with an average of 4.17 × 101 Bq/L which substantially exceed the World Health Organization (WHO) recommended safety threshold of 100 Bq/L for drinking water. The mean annual effective dose from ingestion (3.05 × 10⁻³ mSv/y) remained below the International Commission on Radiological Protection (ICRP) public exposure limit of 1 mSv/y. However, the mean dose to the stomach was 3.65 × 10⁻⁴ mSv/y, indicating minor but quantifiable internal exposure. Notably, the average annual effective dose from inhalation was 18.4 mSv/y, significantly surpassing the ICRP guideline, thus raising potential health concerns, particularly in enclosed, poorly ventilated settings where radon may accumulate. The study therefore recommends continuous monitoring of domestic water sources and improved ventilation practices to minimize radon-related health risks.
Ahmad A. Sule, Ubaidullah Ahmad, Abdulkareem M. Hamza· Journal of Basics and Applie...· 0 citations
In this study, the Alpha Guard PQ2000 PRO detector was used to collect direct water samples from 36 locations southeast of Baghdad Governorate. This included 10 samples collected from the Tuwaitha nuclear site. Twenty-six samples were collected. While outside the Tuwaitha nuclear site, including from health centers, mosques, schools, and gas stations near the Tuwaitha nuclear site. The highest radon concentration in the water tank was recorded at 0.44204 Bq/L at the Central Laboratories Directorate/Model Room (sample W9). In contrast, the lowest concentration was recorded at 0.13364 Bq/L at the Nuclear and Radiation Safety and Security Directorate (sample W11). The annual effective dose from inhalation and ingestion of radon-222 was calculated for all these locations and was found to be lower than the recommended reference level. The natural limit for radon concentration in water is 100 Bq/L according to the World Health Organization, while the Environmental Protection Agency sets a more stringent standard of 11 Bq/L. Radon gas and its short-lived decay products contribute significantly to human exposure to natural radiation, which can cause cancer. Ongoing monitoring is essential to mitigate potential risks.
Ruqayah Mohammed Jawad, Hayder S. Hussain· Iraqi Journal of Physics· 0 citations
Radon-222 (222Rn) in groundwater is a potential source of internal radiation exposure through
ingestion, particularly in regions where groundwater constitutes a major source of drinking
water. This study presents an assessment of 222Rn concentrations, radiological risks, and
measurement uncertainties in groundwater within Kubwa, Abuja, Nigeria, using liquid
scintillation counting. Thirty groundwater samples collected during the peak dry season were
analysed using a calibrated Tri-Carb 1000 TR liquid scintillation analyser, with corrections for
radioactive decay and partitioning effects. The 222Rn concentrations ranged from below the
detection limit to 2.30 Bq L⁻¹, with a mean of 0.29 ± 0.43 Bq L⁻¹. Estimated annual effective
doses were of the order of 10⁻³ mSv y⁻¹, well below the recommended reference level of 0.1
mSv y⁻¹. Expanded relative uncertainties (k = 2) ranged from approximately 6% for higheractivity samples to over 20% for samples near the detection limit. The results indicate a very
low radiological risk from 222Rn ingestion through groundwater and provide baseline data for
the study area. The findings also demonstrate the importance of considering detection limits
and measurement uncertainty in environmental radioactivity assessments.
B. C. Nwankwo, Y. V. Ibrahim· Physics Access· 0 citations
The findings indicate that the investigated water sources may pose potential health risks if consumed without treatment, and appropriate water treatment and routine radiological monitoring are recommended to minimize radon exposure and protect public health.
Aminu Abubakar, B. Ordinioha, A. Kumurya et al.· Journal of Basics and Applie...· 0 citations
Groundwater is the principal drinking-water source on Nigerian university campuses, yet its radiological quality, and the age-differentiated radon doses delivered to the students, staff and resident children who depend on it, remains largely uncharacterised, and no comparative campus-scale assessment exists for the semi-arid basement terrain of Katsina State. This study assessed radon gas concentration and associated radiological health risks in drinking water samples collected from three universities in Katsina State, Nigeria: Federal University Dutsin-Ma (FUDMA), Umaru Musa Yar'adua University, Katsina (UMYU), and Federal University of Transportation Daura (FUTD). A total of 30 water samples were analyzed for radon activity concentration, and the annual effective doses (AED) due to inhalation and ingestion were calculated for adults, children, and infants. Total annual effective doses (TAED) and excess lifetime cancer risks (ELCR) were also determined. Radon concentrations ranged from 10−4 to 1.14×10−1 Bq L−1 at FUDMA, 8×10−3 to 1.875 Bq L−1 at UMYU, and 6.1×10−2 to 12.964 Bq L−1 at FUTD, with mean values of 1.58×10−2, 6.81×10−1, and 4.501 Bq L−1, respectively. All mean concentrations were below the WHO/UNSCEAR safe limit of 11 Bq L−1. However, the Admin Block at FUTD recorded 12.964 Bq L−1, slightly exceeding this threshold. The mean TAED values remained well below the ICRP reference level of 0.1 mSv yr−1 across all institutions, though FUTD's Admin Block slightly exceeded this limit (0.198 mSv yr−1 for infants). ELCR values were generally within acceptable EPA ranges (10−6–10−4), except at FUTD's Admin Block where infant ingestion risk reached 6.61×10−4, nearing the upper bound of acceptability. Infants consistently exhibited the highest doses and cancer risks across all sites, followed by children and adults. The findings indicate that while most water sources are radiologically safe, localized hotspots, particularly at FUTD require continuous monitoring.
A. Z. Namadi, A. Lawal, Kado S. et al.· Journal of Basics and Applie...· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
