Radiological impact of dietary intakes of naturally occurring radionuclides on Pakistani adults

• Published in: Food and chemical toxicology Vol. 45; no. 2; pp. 272 - 277
• Main Authors: Akhter, P., Rahman, K., Orfi, S.D., Ahmad, N.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2007; New York, NY Elsevier Science
• Subjects: Biological and medical sciences; Cancer risk; Diet; Diet Surveys; dietary exposure; Dietary intake; Food Analysis; Food Contamination, Radioactive - analysis; Humans; Life Expectancy; Mass Spectrometry - methods; Medical sciences; mortality; Naturally occurring radionuclides; neutron activation analysis; Neutron Activation Analysis - methods; Pakistan; Pakistani population; pollution; Potassium Radioisotopes - administration & dosage; Potassium Radioisotopes - analysis; Radiation Dosage; Radiation dose; radiation safety; radionuclides; Risk Assessment; Spectrophotometry, Atomic - methods; Thorium - administration & dosage; Thorium - analysis; toxic substances; Toxicology; Uranium - administration & dosage; Uranium - analysis; Pakistan; Naturally occurring radionuclides; Radiation dose; Dietary intake; Pakistani population; Cancer risk; Radiography; Risk factor; Oral administration; Malignant tumor; Cancer
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2006.08.006

Daily dietary intakes of three naturally occurring long-lived radionuclides 232Th, 238U and 40K were estimated for the adult population of Pakistan using neutron activation analysis (NAA), inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), respectively. The daily intakes of 232Th ranged from 4 to 29 mBq, 238U ranged from 17 to 82 mBq and 40K ranged from 51 to 128 Bq. The geometric means of these intakes were 10 mBq d −1 for 232Th, 33 mBq d −1 for 238U and 78.5 Bq d −1 for 40K. The measured values give annual committed effective doses of 0.80, 0.53 and 178.75 μSv yr −1 for 232Th, 238U and 40K, respectively to Pakistani population. The net radiological impact of these radionuclides is 180.08 μSv yr −1. This value gives cancer risk factor of 4.5 × 10 −4 and loss of life expectancy of 0.87 days only. Whereas ICRP cancer risk factor for general public is 2.5 × 10 −3 and total risk involve from the all natural radiation sources based on global average annual radiation dose of 2.4 mSv yr −1 is 6.0 × 10 −3. The estimated cancer risk shows that probability of increase of cancer risk from daily Pakistani diet is only a minor fraction of ICRP values. Therefore, the diet does not pose any significant health hazard and is considered radiologically safe for human consumption.