Biomedical subjects

E A Ough

Publications and source records attributed to E A Ough.

3 recordsLinked to original sources

PubMed2006

Determination of natural and depleted uranium in urine at the ppt level: an interlaboratory analytical exercise.

An analytical exercise was initiated in order to determine those procedures with the capability to measure total uranium and uranium (238U/235U) isotopic ratios in urine samples containing >0.02 microg U kg-1 urine. A host laboratory prepared six identical sets of twelve synthetic urine samples containing total uranium in the range of 25 to 770 ng U kg-1 urine and with 238U/235U isotopic ratios ranging from 138 (100% NU) to 215 (51% DU). Sets of samples were shipped to five testing laboratories (four based in Canada and one based in Europe). Each laboratory utilized one of the following analytical techniques: sector field inductively coupled plasma mass spectrometry (ICP-SF-MS), quadrupole inductively coupled plasma mass spectrometry (ICP-Q-MS), thermal ionization mass spectrometry (TIMS), and instrumental/delayed neutron activation analysis (I/DNAA), in their analyses.

Canada↗

PubMed2002

An examination of uranium levels in Canadian forces personnel who served in the Gulf War and Kosovo.

A uranium bioassay program was conducted involving 103 active and retired Canadian Forces personnel. The total uranium concentrations in each of two 24-h urine collections were analyzed separately at independent commercial laboratories by inductively coupled plasma mass spectrometry (ICP-MS) and by instrumental neutron activation analysis (INAA). The mean and median concentrations were determined to be 4.5 ng L(-1) and 2.8 ng L(-1), respectively, from ICP-MS and 17 ng L(-1) and 15 ng L(-1), respectively, from INAA. The total uranium concentrations were sufficiently low so that isotopic (238U:235U ratio) assays could not be performed directly from urine samples. Isotopic assays were performed on hair samples from 19 of the veterans participating in the testing. The isotopic hair assays were scattered around the natural 238U:235U ratio of 137.8, ranging from 122 +/- 21 to 145 +/- 16 (1sigma). Due to concern expressed in the media over possible depleted uranium exposure and long-term retention in bone, a single bone sample (vertebrate bone marrow) from a deceased member of the Canadian Forces was also analyzed for total uranium content and isotopic ratio by ICP-MS. The sample was shown to have 16.0 +/- 0.3 microg kg(-1) uranium by dry weight and a 238U:238U isotopic ratio of 138 +/- 4, consistent with natural uranium.

Canada↗

PubMedDate not supplied

Bubble detector characterization for space radiation.

In light of the importance of the neutron contribution to the dose equivalent received by space workers in the near-Earth radiation environment, there is an increasing need for a personal dosimeter that is passive in nature and able to respond to this neutron field in real time. Recent Canadian technology has led to the development of a bubble detector, which is sensitive to neutrons, but insensitive to low linear energy transfer (LET) radiation. By changing the composition of the bubble detector fluid (or "superheat"), the detectors can be fabricated to respond to different types of radiation. This paper describes a preliminary ground-based research effort to better characterize the bubble detectors of different compositions at various charged-particle accelerator facilities, which are capable of simulating the space radiation field.

Calibration↗