RESUMO
BACKGROUND: We investigated the human risk due to radon and heavy metals (HM) in soil. METHODS: Samples were collected in 2017 from 10 representative geographical locations at Jazan region of southwestern Saudi Arabia and analyzed for elements (Al, Ca, Cu, Ni, Sr Fe, Mg, B, Co, Cr, V, Zn, Mn, Ba, Cd, and Pb). Elements were measured using inductively coupled plasma optical emission spectrometer (ICP-OES). Radon (Rn) was measured using solid-state nuclear detector (SSNTDs). RESULTS: The maximum human risk was due to Al, which had the highest concentration, where the lowest human risk was due to Cd. The maximum radon concentration was obtained at El-Mazab area with value of 381.05 Bq/m3which leads to 6.55 mSv/y and 78.94 Bq/m2d annual effective doses and radon exhalant rate respectively. Average equivalent and effective dose to different organs due to radon concentration was estimated. Hazard Index due to both carcinogenic and non-cancer hazards were calculated it exceeds permissible level for child due to Nickel and Chromium hence there is a significant risk on children in the study area. CONCLUSION: HM concentrations were over limits in some places according to the human activities, municipal waste disposal, fertilizers and pesticides in agriculture. In addition, soil is porous permit dispersion of radon to the atmosphere.
RESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMO
Arab Abu Saed area in Giza governorate, south to Cairo contains more than 228 clay brick kilns represent the largest cluster of brickworks in Egypt. Burning of Heavy Fuel Oil (HFO) in such kilns is the main source of air pollution in the surrounding locations. In this study, investigation of switching the fuel used in brick kilns from (HFO) to Natural Gas (NG) is carried out and the pollution loads are assessed in both cases. In addition, two Gaussian dispersion plume models are employed to estimate the concentration of primary pollutants; PM10, SO2, and NO2 at seven locations in the vicinity of Arab Abu Saed to determine the most adversely affected locations. Statistical analysis is applied to evaluate the correlation and conformity of the results of both models. Results show that using of NG leads to a significant reduction of pollution loads of PM10, SO2 and NO2 reaches 96%, 72%, and 24% respectively. In addition, the reduction of naturally occurring radionuclides in air is analyzed. Activity concentrations of Ra-226, Th-232 and K-40 in Bq/l for HFO were measured using HPGe detector for six HFO samples. Exposure due to air submersion of naturally occurring radionuclides in the study area leads to annual equivalent dose ranged between 2.16 mSv/y (received by Uterus) and 14 mSv/y (received by skin), and average effective dose 2.65 mSv/y which represent valuable exposure.
RESUMO
In this paper, we used the Hyper-Pure Germanium (HPGe) detector to measure 30 samples which are collected from north of Nile Delta near Rosetta beach in Egypt. The activity of primordial radionuclides, such as 238U, 235U, 232Th, and 40K was estimated. Concentrations ranged between 36.5-177.4, 50-397.5 and 56.1-168.9 Bq.kg-1 for 238U, 232Th and 40K respectively. Activity concentration of 235U and the variation in uranium isotopic ratio 235U/238U was calculated. External hazard indices (Hex) (or radium equivalent activity Raeq), activity concentration indices (I), alpha index (Iα), absorbed outdoor gamma dose rate (Dout), effective outdoor gamma dose rate (Eout) and Excess Lifetime Cancer Risk (ELCR) due to different samples are estimated. External hazard indices (Hex) are ranged between 0.32-2.04, radium equivalent activity (Raeq) are ranged between 118.67-753.91, the activity concentration indices (I) are 0.42-2.61, and alpha index (Iα) are 0.18-0.89. External hazard indices (Hex) in some samples more than unity then it exceeds the upper limit of exposure. Also, the radium equivalent activities (Raeq) are higher than the exemption limits (370 Bq.kg-1).
