Activated charcoal filter counting for radioiodine effluent concentration determination in protein iodinations

Terry M. Button, Robert G Hamilton

Research output: Contribution to journalArticle

Abstract

Regulatory agencies have recently placed emphasis upon quantification of I released to the environment during protein iodinations at radioiodination facilities. This necessitates air sampling in order to determine the concentration of 125I in the effluent. Air sample trapping mechanisms generally employed are activated charcoal filters. Difficulty arises in quantifying the activity of 125I trapped because of the attenuation of the 125I decay photons by the charcoal. Evaluation of the activity incident upon commercially available filters using a scintillation detector and large detector source separation is considered here. It is demonstrated that the activity in the filter may be treated as an exponential distribution within an attentuating matrix. This treatment essentially adds a constant correction factor to the counting efficiency of a given geometry for a filter-affluent flow rate combination. Finally, it is shown that an approximation assuming a uniform distribution of activity produces a large error in correction factor to the counting efficiency for the filters examined.

Original languageEnglish (US)
Pages (from-to)853-857
Number of pages5
JournalHealth Physics
Volume43
Issue number6
StatePublished - 1982
Externally publishedYes

Fingerprint

charcoal
Halogenation
Charcoal
effluents
Effluents
counting
Air
effluent
filter
proteins
filters
Source separation
Scintillation counters
protein
Photons
Proteins
Flow rate
Sampling
Detectors
air sampling

ASJC Scopus subject areas

  • Health, Toxicology and Mutagenesis
  • Epidemiology
  • Radiology Nuclear Medicine and imaging
  • Environmental Science(all)
  • Environmental Science (miscellaneous)
  • Environmental Chemistry
  • Public Health, Environmental and Occupational Health
  • Toxicology
  • Physics and Astronomy (miscellaneous)

Cite this

Activated charcoal filter counting for radioiodine effluent concentration determination in protein iodinations. / Button, Terry M.; Hamilton, Robert G.

In: Health Physics, Vol. 43, No. 6, 1982, p. 853-857.

Research output: Contribution to journalArticle

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