The self-defining critical group and its application to a measured check of the derived limit for [sup 125]I in drinking water

Journal Article · Tue Dec 01 00:00:00 EST 1992 · Health Physics; (United States)

DOI:https://doi.org/10.1097/00004032-199212000-00010· OSTI ID:7120671

Bowlt, C; Howe, J R ^[1]

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1. Medical College of St. Bartholomew's Hospital, London (United Kingdom)

Using a series of daily measurements of [sup 125]I in the drinking water of North Surrey, England, from November 1988 through May 1990, the accumulated activities in the thyroids of adults drinking such water were calculated on the assumption that the fraction of ingested iodine taken up by the thyroid was f = 0.3 and the tap water consumption was C = 600 L y[sup [minus]1]. These figures were compared with measured values of [sup 125]I activities in 42 thyroids taken at necropsy from residents in the North Surrey area who were dying during this same time period. Eight thyroids (19%) had measured activities greater than predicted, so they were named the self-defining critical group. After comparing the thyroid with the drinking water activity, the current generalized derived limit for [sup 125]I in the drinking water may be too high by a factor of 2. The reason for this appears to be the use of f = 0.3 which is the mean value for the normal' population. Models involving critical groups should use values of parameters different from the mean. In the present case, making f = 0.6 would remove the discrepancy between measurement and prediction and would be in reasonable accord with measured distributions of f.

• OSTI ID: 7120671
• Journal Information: Health Physics; (United States), Vol. 63:6; ISSN 0017-9078
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
59 BASIC BIOLOGICAL SCIENCES
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
DRINKING WATER
MAXIMUM ACCEPTABLE CONTAMINATION
IODINE 125
BIOLOGICAL ACCUMULATION
MAXIMUM PERMISSIBLE INTAKE
MAXIMUM PERMISSIBLE LEVEL
MONITORING
THYROID
ADULTS
HUMAN POPULATIONS
MAXIMUM PERMISSIBLE EXPOSURE
WATER POLLUTION
WATER SUPPLY
AGE GROUPS
BETA DECAY RADIOISOTOPES
BODY
CONTAMINATION REGULATIONS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENDOCRINE GLANDS
GLANDS
HYDROGEN COMPOUNDS
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IODINE ISOTOPES
ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANS
OXYGEN COMPOUNDS
POLLUTION
POLLUTION REGULATIONS
POPULATIONS
RADIOISOTOPES
REGULATIONS
SAFETY STANDARDS
STANDARDS
WATER
540330* - Environment
Aquatic- Radioactive Materials Monitoring & Transport- (1990-)
540320 - Environment
Aquatic- Chemicals Monitoring & Transport- (1990-)
550500 - Metabolism
552000 - Public Health