Fecal analyses

Urinalysis is perhaps the most common form of bioassay measurement. It is routinely performed as part of periodic bioassay program even when intakes are not suspected due to the relative cost and quickness of this type of bioassay. Fecal analyses are generally only performed when an intake is suspected because the excretion of radioactive material in the feces is highest in the first few days immediately following the incident. After that, urinary excretion is more common and more likely to detect an intake. 

In vitro analyses of americium are routinely performed in situations where in vivo analyses cannot be obtained or in support of an in vivo monitoring program. Urine is the preferred sample for in vitro analyses of americium, although other sample types, such as feces, tissue, bone, or blood, can also be used on a more limited basis. Urine provides for an analysis of soluble or transportable americium, fecal analysis can be used to measure ingestion or clearance of americium, and tissue is used to assess whole or regional body burdens of americium (Guilmette and Bay 1981 Ide 1986 Ide et al. 1985 Mclnroy et al. 1985). 

Combining clinical and epidemiological features with fecal analysis gives important clues to the etiological diagnosis. For example, any patients with diarrheal illness lasting more than 1 day, accompanied by fever, bloody... 

Because silver is eliminated primarily through the feces, recent exposure is most easily monitored through fecal analysis. Measurements of silver in the blood are also significant and indicate exposure to the metal. However, silver is not always detected in the urine samples of workers with known exposure to the chemical, and is not as reliable a biomarker as feces and blood. DiVincenzo et al. (1985), for example, detected silver in 100% of feces samples and only 6% of urine samples from workers chronically exposed to silver compounds in air. Increased blood silver levels, above the detection limit for silver (0.6 pig/100 mL blood), have been associated with inhalation exposure to the metal in a study by Rosenman et al. (1979). 

Fecal analysis. Occult blood, fluid content, and toxicant and metabolite levels should be assessed if needed. 

The excretion of uranium in fecal material results primarily from intakes by ingeshon, and includes uranium swallowed after inhalation. Usually, uranium will appear in feces within hours after intake thus providing a rapid means of determining whether an intake has occurred. Fecal analysis requires prechemistry preparation that includes ashing of the sample, cleaning by co-precipitation, and solvent extraction followed by electrodeposition. Alpha spectroscopy is then performed (Singh and Wrenn 1988). Urinalysis is typically favored over both fecal and blood analysis because it is generally more sensitive and less costly, and because fecal analysis provides no uptake or retention information and blood analyses is invasive. 

For urine analysis sample aliquots are diluted 1 1 with distilled water before application to the AAS stabilized temperature platform (Leung and Henderson, 1982). Fecal analysis require considerably more complicated preparation steps than serum or urine. The procedure developed in the author s laboratory (Brown et al., manuscript in preparation) is summarized as follows Frozen specimens are thawed and distilled water is added (1 mL per 2 g feces) and the sample is homogenized in a sealed container on a paint shaker. A 10 mL aliquot is ashed at 550°C in a muffle furnace, dissolved in dilute HNO3 snd analyzed by GF-AAS. 

Balance studies involving aluminium make it necessary to perform fecal analysis. A recent report for the authors laboratory describe methods of collection, shipping and analysis of these types of specimens (Brown et al., manuscript in preparation). 

Normocholesterolemic women (without obesity) excrete and synthesize distinctly smaller amounts of bile acids than males (63) (Table II). The sex difference, however, almost disappears when the values are expressed per kilogram of body weight, though even then the bile acid production tends to be higher in males (4.20 0.27 mg/kg) than in females (3.27 0.31 mg/kg). Thus the possibility of an actual sex difference in bile acid metabolism is not excluded. Furthermore, women tend to eliminate slightly less cholesterol in the form of bile acids (28 % of balance) than men (33 %). Table II shows bile acid production in both sexes as measured by fecal analysis in various conditions with abnormalities in lipid metabolism. 

Fecal analysis provides the best index of an oral exposure to nickel and expired air should be the specimen for chemiluminescent detection of nickel carbonyl following inhalation of this toxic vapor [62]. Analyses of nickel in other specimens, such as saliva, sweat, milk, and hair, are only useful in special cases. 

There are four main types of bioassay measurements urinalysis, fecal analysis, whole body counting, and lung or chest counting. The first two constitute in vitro analyses, and... 

The water analysis is incomplete unless the number of coliform bacteria present is determined as well. A multiple-tube fermentation technique can be used to enumerate positive presumptive, confirmed, and fecal coliform tests. Results of the tests are expressed in terms of the most probable number (MPN). That is, the count is based on a statistical analysis of sets of tubes in a series of serial dilutions. MPN is related to a sample volume of 100 ml. Thus, an MPN of 10 means 10 coliforms per 100 ml of water. 

Table 2. Normal fecal flora a Bacteriological analysis of the normal fecal flora...

Fearragillin, registered for use in aquaculture in Europe, 3 220t Feather meal, 10 856 Fe-base superalloys, 13 503 Fecal coliform analysis, of water, 26 45—46 Fe-complexed dyes, 9 446—447. See also Iron entries... 

Mean fecal calcium loss at high levels of calcium intake was 75.0 mg and at low calcium intake was 16.0 mg. Mean calcium and phosphorus levels are illustrated in Figure 6. Orthogonal contrast analysis indicated that the level of calcium in the ration was the only significant source of difference in the data. 

Sample preparation is rather involved. A sample of urine or fecal matter is obtained and treated with calcium phosphate to precipitate the plutonium from solution. This mixture is then centrifuged, and the solids that separate are dissolved in 8 M nitric acid and heated to convert the plutonium to the +4 oxidation state. This nitric acid solution is passed through an anion exchange column, and the plutonium is eluted from the column with a hydrochloric-hydroiodic acid solution. The solution is evaporated to dryness, and the sample is redissolved in a sodium sulfate solution and electroplated onto a stainless steel planchette. The alpha particles emitted from this electroplated material are measured by the alpha spectroscopy system, and the quantity of radioactive plutonium ingested is calculated. Approximately 2000 samples per year are prepared for alpha spectroscopy analysis. The work is performed in a clean room environment like that described in Workplace Scene 1.2. 

Analysis of Coprostanol An Indicator of Fecal Contamination 815R03003 Analytical Feasibility Support Document for the Six-Year Review of... 

T. Kishida, F. Taguchi, L. Feng, A. Tatsuguchi, J. Sato, S. Fujimori, H. Tachikawa, Y. Tamagawa, Y. Yoshida and M. Kobayashi, Analysis of bile acids in colon residual liquid or fecal material in patients with colorectal neoplasia and control subjects, J. Gastroenterol., 1997, 32, 306. 

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