AN INTERNATIONAL COOPERATION BY USING AN ALL-ENCOMPASSING PASSIVE RADON MONITOR.

The recently developed radon film-badge makes it possible to measure radon indoors, in soil, in water and/or in aqueous media (e.g. mud). As a result of its wide response linearity, this monitor has been successfully used to measure radon in-water with concentrations from 10 to ~10 000 Bq/L. By exploiting the unique characteristics of this badge, a mini-survey has been carried out by Health Canada in which radon in water was measured from 12 private wells, as well as in tap water originating from the Ottawa River. Due to the widespread interest of different laboratories in using these passive monitors, laboratories were provided with plastic films to construct their own badges by using in-house CR-39 detectors. Monitors were then irradiated by a known radon concentration at the National Institute of Radiation Metrology (ENEA)'s radon chamber and sent back to each laboratory for processing and counting. Even though these laboratories have been using different etching- and counting-procedures, the film-badge responses varied only within ~12%.

A test of radon service providers available on the Internet.

UNLABELLED: With the announcement of the Government of Canada's Radon Guideline and increased public awareness of radon risk, more and more Canadians wish to test their homes for radon. Radon service providers available on the Internet have attracted many homeowners' attention. These services provide an easy and less expensive way for homeowners to test radon levels in their homes. However, a question has frequently been asked, 'How reliable are the radon testing services available on the Internet?' To answer this question, we ordered 36 radon testing kits from 10 service providers on the Internet. The test results showed that online radon testing services could collectively meet the performance requirement. However, the quality of a few service providers needs to be improved. PRACTICAL IMPLICATIONS: Indoor radon tests were performed with detectors ordered from 10 service providers available on the Internet. The results showed that online radon testing services could collectively meet the performance requirement. However, the quality of a few service providers needs to be improved.

Uranium gastrointestinal absorption: the f1 factor in humans.

The present investigation was undertaken by the Department of Health, Canada, to determine the most appropriate value to use for uranium gastrointestinal absorption (f1) in setting the guideline for drinking water. Fifty participants, free from medical problems, were recruited from two communities: a rural area where drinking water, supplied from drilled wells, contained elevated levels of uranium and an urban area where the water supplied by the municipal water system contained < 1 microg l(-1). Uranium intake through food, drinking water and other beverages was monitored using the duplicate diet approach. Intake and excretion were measured by inductively coupled plasma-mass spectrometry (ICP-MS) in samples collected concurrently from the same individuals over a 3 d period. The range of f1 values was between 0.001 and 0.06, with a median of 0.009. These values were independent of gender, age, duration of exposure, daily total uranium intake and allocation of intake between food and water. Consistent with the recommendation of ICRP Publication 69, 78% were below 0.02.