scholarly journals Radionuclide Content of Aerosols within the Lower Atmosphere of Major Towns in Plateau State, North Central Nigeria

2021 ◽  
Vol 4 (1) ◽  
pp. 161-167
Author(s):  
T Sombo ◽  
S Entonu ◽  
T Igbawua ◽  
JT Shivil

Radioactivity analysis of aerosols within the lower atmosphere of some selected towns in Plateau state, North central Nigeria was carried out using Respirable Dust sampler (APM 460NL) and Gamma Ray Spectroscopy technique to ascertain their radiological safety and radiation dose to the general public. The mean mass concentration of fine (PM2.5) and coarse (PM10) aerosols were found to be 234.4 and 390.6 (ug/m3) respectively for Pankshin; 381.3 and 312.5  (ug/m3) respectively for Shendam, and 208.3 and 250.0   (ug/m3) for Jos. The mean activity concentration of Potassium- 40, Radium-226 and Thorium-232 in the selected towns were found to be 510.82,52.16 and 29.76 Bq/kg respectively. Average values of the following radiological parameter Da, AEDE, HEX and AGED were 4.3439 nGy/yr, 0.0053MSv/yr,0.025Bq/kg, and 30.3470 mSv/yr respectively.The activity concentration of Potassium-40 was beyond the permissible limit at Shandan while that of Radium-226 was beyond the set limit in Jos and Pankshin. The concentration of Thorium-232 in the study areas was below permissible limit. Continuous exposure to these radionuclides and their progenies including their synergetic effects with trace metals in the aerosols may pose several risk to public health. This work is useful in regional environmental radiation monitoring and is part of efforts geared towards generating baseline data for environmental radioactivity levels within North Central Nigeria .

Author(s):  
Ayorinde Ogunremi ◽  
Adeola Olaoye Morounfolu

Monitoring of environmental radiation helps to ascertain healthy vicinity which is a catalyst to the economic development of the area. Activity concentration of naturally occurring radionuclides in three (3) dumpsites in Lagos State, Olusosun Landfill, Ojota, Ilupeju dumpsite and, Gbagada dumpsite Lagos state, Nigeria were investigated using gamma-ray spectroscopy to obtain the level of radioactive exposure hazards experienced by people living in these vicinities. A total of thirty soil samples were randomly collected into a polythene bag. They were oven-dried at 110°C, pulverized, and sieved. Quantities of the samples (400 g) were sealed in cylindrical sample holders and kept for about 28 days to attain secular equilibrium between 226Ra and its decay products before analysis using gamma-ray spectrometry. The mean activity concentration obtained for 40K, 238U, and 234Th at, Ilupeju, Gbagada, and Ojota were 339.23±33.66, 11.83±19.174, 11.95±22.752 Bq/kg, 337.56 ± 36.22, 11.49±22.14, 11.54 ± 19.33 Bq/kg and 334.87±32.44, 11.42±22.39, 11.56±18.52 Bq/kg respectively. The mean absorbed dose nGy/h, annual effective dose mSv/y were calculated and their results were found to be below the global values. The results indicate that the radiation level within the dumpsites poses no significant health risk to the people living close to the dumpsites.


1987 ◽  
Vol 26 (03) ◽  
pp. 143-146 ◽  
Author(s):  
H. Fill ◽  
M. Oberladstätter ◽  
J. W. Krzesniak

The mean activity concentration of1311 during inhalation by the nuclear medicine personnel was measured at therapeutic activity applications of 22 GBq (600 mCi) per week. The activity concentration reached its maximum in the exhaled air of the patients 2.5 to 4 hours after oral application. The normalized maximum was between 2 • 10−5 and 2 • 10−3 Bq-m−3 per administered Bq. The mean activity concentration of1311 inhaled by the personnel was 28 to 1300 Bq-m−3 (0.8 to 35 nCi-rrf−3). From this the1311 uptake per year was estimated to be 30 to 400 kBq/a (x̄ = 250, SD = 50%). The maximum permitted uptake from air per year is, according to the German and Austrian radiation protection ordinances 22/21 µiCi/a (= 8 • 105 Bq/a). At maximum 50% and, on the average, 30% of this threshold value are reached. The length of stay of the personnel in the patient rooms is already now limited to such an extent that 10% of the maximum permissible whole-body dose for external radiation is not exceeded. Therefore, increased attention should be paid also to radiation exposure by inhalation.


Author(s):  
Matti T Nghikembua ◽  
Laurie L Marker ◽  
Bruce Brewer ◽  
Arvo Leinonen ◽  
Lauri Mehtätalo ◽  
...  

Abstract Bush encroachment affects ~45 million ha of Namibia and, without appropriate restoration measures, it negatively affects rangeland productivity and biodiversity. Thinning is a common method to counteract bush encroachment. The thinning strategy applied in north-central Namibia was assessed to examine how effective it has been in reducing bush encroachment. Trees/shrubs were selectively thinned manually, targeting all height classes, except individuals with stem diameters ≥18 cm. We investigated the effects on the vegetation and soil properties using surveys on three freehold farms (in 2016 and 2017) in bush-encroached and previously thinned habitats. Our results revealed significant differences in the mean total nitrogen (TN) content between the treatments; thinned areas had higher TN content which would be beneficial for fast-growing grasses. In the thinned plots, the occurrence probability of red umbrella thorn (Vachellia reficiens Warwa) was significantly reduced, indicating that it was the most harvested species; and umbrella thorn (Vachellia tortilis (Burch.) Brenan spp. heteracantha) was increased, indicating that it favoured reduced densities of dominant species. Natural regeneration was rapid; the tree/shrub abundance in the 0–1-m height class in the thinned area surpassed those in the non-thinned by 34 per cent, ~7.2 years since thinning. Thinning significantly reduced tree/shrub abundances of the 1–3- and >3-m height classes, which was still evident 7.2 years since thinning. Based upon the generalized linear mixed-effects model, tree/shrub counts between treatments may equalize in ~14 and 15 years for the 1–3- and >3-m height classes, respectively. Thinning was effective in reducing tree/shrub abundances and can be used to restore wildlife habitat on the Namibian farmland: however, post-thinning management is required to maintain an open savannah vegetation structure as the 0–1-m height class cohort will eventually grow into mature trees/shrubs.


2017 ◽  
Vol 75 (3) ◽  
pp. 199-204 ◽  
Author(s):  
Lucie Fournier ◽  
Enora Cléro ◽  
Eric Samson ◽  
Sylvaine Caër-Lorho ◽  
Dominique Laurier ◽  
...  

ObjectivesThe French nuclear worker cohort allows for the assessment of cancer risk associated with occupational radiation exposure, but workers are also exposed to medical and environmental radiation which can be of the same order of magnitude. This study aims to examine the impact of non-occupational radiation exposures on the dose-risk analysis between occupational radiation exposure and cancer mortality.MethodsThe cohort included workers employed before 1995 for at least one year by CEA, AREVA NC or EDF and badge-monitored for external radiation exposure. Monitoring results were used to calculate occupational individual doses. Scenarios of work-related X-ray and environmental exposures were simulated. Poisson regression was used to quantify associations between occupational exposure and cancer mortality adjusting for non-occupational radiation exposure.ResultsThe mean cumulative dose of external occupational radiation was 18.4 mSv among 59 004 workers. Depending on the hypotheses made, the mean cumulative work-related X-ray dose varied between 3.1 and 9.2 mSv and the mean cumulative environmental dose was around 130 mSv. The unadjusted excess relative rate of cancer per Sievert (ERR/Sv) was 0.34 (90% CI −0.44 to 1.24). Adjusting for environmental radiation exposure did not substantially modify this risk coefficient, but it was attenuated by medical exposure (ERR/Sv point estimate between 0.15 and 0.23).ConclusionsOccupational radiation risk estimates were lower when adjusted for work-related X-ray exposures. Environmental exposures had a very slight impact on the occupational exposure risk estimates. In any scenario of non-occupational exposure considered, a positive but insignificant excess cancer risk associated with occupational exposure was observed.


2012 ◽  
Vol 52 (4) ◽  
pp. 421-434 ◽  
Author(s):  
Grzegorz Lemańczyk

AbstractIn the field study period from 2006 to 2010, the incidence and severity of sharp eyespot caused byRhizoctoniawere recorded on 36 cultivars of triticale at the milk ripe growth stage. Four localities in north-central Poland were included: Chrząstowo, Dębina, Kończewice and Minikowo. The susceptibility of the seedlings of 30 cultivars of triticale toR. cerealis(AG-D subgroup I) andR. solani(AG-5) was studied in the laboratory. There was much variation in incidence and severity of sharp eyespot between years and locations. The disease was most intense at Chrząstowo. At this location, the mean percentage of diseased stems on 28 cultivars was 2.6-35.7 (-55.0), and the mean disease index was 0.7-15.6 (-24.5), with the lowest and highest values in 2008 and 2009, respectively. At Minikowo, the disease was least intense. At this location, the mean percentage of diseased stems on 23 cultivars was 1.0-4.6 (-18.0), and the mean disease index was 0.3-1.4 (-6.3), with the lowest and highest values in 2006 and 2007, respectively. The cultivars with least intense disease were Tulus and Atletico (Chrząstowo), Grenado and Zorro (Dębina), Krakowiak and Tornado (Kończewice), and Woltario and Constans (Minikowo). The cultivars with most intense disease were Alekto (Chrząstowo), Baltiko (Dębina), Pawo (Kończewice) and Borwo (Minikowo). MostlyR. cerealiswas isolated from the diseased stems;R. solaniwas isolated only sporadically. There was a wide variation in the susceptibility of triticale cultivars toRhizoctonia. Most triticale seedlings inoculated withR. cerealisproduced symptoms typical of sharp eyespot. Seedlings inoculated withR. solaniformed extended lesions with no defined borders. Most symptoms developed on coleoptiles, with less symptoms on the leaves and the least on the roots. There was much variation in susceptibility of triticale cultivars to bothRhizoctoniaspecies. Cultivars were grouped into six categories according to the intensity of seedling infection. Categories 1, 2 and 3, representing low, moderate and high susceptibility toR. cerealis, included 17, 10 and 3 cultivars, respectively.Categories 4, 5 and 6, representing low, moderate and high susceptibility toR. solani, included 3, 12 and 15 cultivars, respectively.Cultivars Baltiko and Zorro had low, and cv. Cultivo had high susceptibility to bothRhizoctoniaspecies. No cultivar was resistant toRhizoctonia. There was a positive correlation between infection byR. cerealisandR. solani.Infection of coleoptiles byR. cerealisorR. solaniwas significantly correlated with infection of leaves. No correlation between intensity of sharp eyespot on triticale plants in the field and on seedlings in controlled conditions was found.


2021 ◽  
Vol 877 (1) ◽  
pp. 012004
Author(s):  
N S Hadi ◽  
Z S Jabbur

Abstract A total with 15 samples was collected from 3 wells in the aljazaier distreet in Babil governorate for the period from January to April 2020, to study the microbial contamination represented by fecal bacteria, while chemical contamination includes a physochemical and the heavy element’s properties. The goal of this study: Study the water of some wells from some microbes and chemical aspects and evaluate this according to Iraqi standards and specifications. Results showed microbial pollution by fecal Coliform bacteria in well water when using Using the agar media. Results showed the difference in the mean of (MPN) of well water. It was found that the EC value (1061) μs/cm was exceeded the permissible limit in W1, Cl values (325, 430)mg/l, pb values (0.43, 0.14) μg/l and Ni values (0.11, 0.11) μg/l and the permissible limit were exceeded in W1, W2 and SO4 values (681, 653, 584) mg / l also the permissible limit was exceeded in W1, W2 and W3 as well as Ag value (0.12) μg/l is in W1 only. The total risk index (HIT) in the groundwater for W1, W2, W3 was acceptable for adult values ΣHI( 0.23, 0.97, 3.8E-4 ) and children values ΣHI ( 2.6E-2, 1.6E-2, 1.3E-3 ) respectively.


Author(s):  
Ahmed F. Mkhaiber ◽  
Auday T. Al-Bayati ◽  
Enas A. Jawad ◽  
Khalid H. Mahdi

The normal radioactivity levels of Uranium-238, Thorium-232, and Potassium-40 were calculated for ten types of foreign and local cigarettes available on the Iraqi market using a gamma-ray spectroscopy technique employing the germanium detector system. The results of this study showed that the average specific activity for each of Uranium-238, Thorium-232 and Potassium-40 were 21.689± 4.596, 18.906 ± 4.148, and 430.094 ± 19.449 (Bq/Kg) respectively. The annual effective dose, radium equivalent activity and excess lifetime cancer risk for the studied samples were also calculated, and their rates were 11.582 μsv/y, 81.841 Bq/Kg, and 40.538 people per million per year respectively. The outcomes indicate that the rate of concentration of uranium and thorium is lower than the permissible values, whereas the average concentration of potassium was slightly higher than the permissible values. This research is important because it warns against several types of cigarettes that contain high concentrations of radionuclides, which can lead to infection cancer and then lead to the death of the person who has used it profusely. Therefore, the aim of the current research is to evaluate the radiological risks of radionuclides in tobacco cigarette smoke by evaluating their natural radionuclide concentrations.


2021 ◽  
Author(s):  
Amethyst Johnson ◽  
Karen Aplin

<p>Planetary atmospheric electrification has the potential to damage spacecraft, yet for planets with thick, deep atmospheres such as Venus, the level of electrification remains open to interpretation. Partly due to the difficulty of access and potential hostility to spacecraft, there are limited in-situ observations of deep atmospheres, making terrestrial analogies attractive. One proposed explanation of the observations of near-surface electrification on Venus from sensors on Venera 13 & 14 is a haze of charged aerosol. As the Sahara is an environment with lofted dust that is potentially similar to Venus in terms of atmospheric stability, a simple model was developed estimating a mean aerosol charge based on typical Saharan haze aerosol distributions. Spacecraft surface area and descent speeds were used to estimate the accumulated charge and discharge current measured by the Venera missions, but this model underestimated Venera's electrical measurements by three orders of magnitude. This suggests that an aerosol layer alone cannot explain the charge apparently present in the lower atmosphere of Venus. The simple terrestrial analogy employed may not have been suitable due to the modified pressure and temperature profile affecting the mean free path, ionic mobility and consequently the mean charge. Discrepancies in atmospheric stability and wind patterns must also be evaluated, as the effect of terrestrial wind on aerosol distributions may not be directly applicable to other planets. More detailed calculations of ion-aerosol attachment and re-evaluation of the terrestrial analogy may be able to resolve some these issues, but it looks likely that additional significant sources of charge are required to explain the Venera observations. Triboelectric charging of lofted surface material could exceed charging observed in terrestrial situations, or some unknown atmospheric or non-atmospheric source of charge could have contributed to the Venera electrical measurements. </p>


2017 ◽  
Vol 19 (1) ◽  
pp. 56 ◽  
Author(s):  
RoseO Abah ◽  
SelineN Okolo ◽  
Collins John ◽  
MarthaO Ochoga ◽  
RuthO Adah

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