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SUMMARY:Natural Radioactivity in soils of Ijero\, Nigeria: measurements an
 d risk assessment
DTSTART;VALUE=DATE-TIME:20190319T081500Z
DTEND;VALUE=DATE-TIME:20190319T083000Z
DTSTAMP;VALUE=DATE-TIME:20260411T015436Z
UID:indico-contribution-1312@indico.tlabs.ac.za
DESCRIPTION:Speakers: Tarryn Bailey (student)\nSoil samples were obtained 
 from Ijero\, Nigeria where the chemical and radiotoxicity of soil is under
  question due to ongoing and unprofessional mining activities. The soil sa
 mples were crushed\, sieved\, dried and sealed in identical cylindrical co
 ntainers. The activity concentration of primordial radionuclides 238U\, 23
 2Th and 40K was measured using a High-Purity Germanium (HPGe) detector cou
 pled with the Palmtop MCA. Subsequently\, radiological risk factors were c
 alculated to assess the risk\, on average\, to an individual living in Ije
 ro. \nThe measured activity concentration for 238U ranged from 11.87±1.06
  to 94.02±6.81 Bq/kg with a mean value of 40.76 Bq/kg. For 232Th the acti
 vity concentration ranged from 18.29±6.71 to 111.2±1.89 Bq/kg with a mea
 n value of 43.59 Bq/kg. Finally\, 40K ranged from 66.56±26.2 to 1195±35.
 8 Bq/kg with a mean value of 568.1 Bq/kg. Thus the mean values for the act
 ivity concentration of primordial radionuclides 238U\, 232Th and 40K were 
 higher than the global averages of 30 Bq/kg\, 39 Bq/kg and 400Bq/kg respec
 tively.\nIn total\, 30 soil samples were evaluated. Of these samples\, onl
 y 1 had hazard indices outside of the permissible limit of 1 mSv/yr. Exact
 ly 10 samples were above the permissible limit for the Annual Effective Do
 se rate\, where indoor and outdoor dose rates must sum to 1 mSv/yr. The An
 nual Gonadal Equivalent Dose limit of 300 µSv/yr was surpassed by 25 samp
 les. For the Excess Lifetime Cancer Risk and Percentage Risk\, 7 samples w
 ere outside of the 5% limit\, with the highest risk at 61%. The average ri
 sk across all the soil samples was well below the limit. Therefore there a
 re certain high risk locations where the activity concentration of primord
 ial radionuclides is significant in Ijero\, Nigeria.\n\nhttps://indico.tla
 bs.ac.za/event/82/contributions/1312/
LOCATION:J Block Auditorium
URL:https://indico.tlabs.ac.za/event/82/contributions/1312/
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