Feces analysis

The most useful application of ISS is in the detection and identification of sur-fece contamination, which is one of the major causes of product failures and problems in product development. The surface composition of a solid material is almost always different than its bulk. Therefore, surface chemistry is usually the study of unknown surfaces of solid materials. To better understand the concept of surface analysis, which is used very loosely among many scientists, we must first establish a definition for that term. This is particularly Important when considering ISS... 

Radioactivity Analysis. Samples of urine, feces, and tissues were combusted to COo and analyzed for radioactivity (5). By using this method the recovery of radioactivity from samples spiked with C was 95 dt 5%. To determine the radioactivity expired as CO2, 5-ml aliquots of the solution used to trap the CO2 were added to 15 ml of a scintillation counting solution containing 4 grams 2,5-diphenyloxazole (PPO) and 0.1 grams l,4-bis-2(5-phenyloxazolyl)-benzene (POPOP) per liter of 1 1 toluene 2-methoxyethanol. Samples were counted for radioactivity in a Nuclear Chicago Mark II liquid scintillation counter. Counting eflSciency was corrected by the internal standard technique. 

In an analytical laboratory, there must be complete confidence between laboratory and client. All results belong to the client and must not be disclosed to others. There was a case, for instance, where some special methods were developed in connection with a nutritional study. This involved an analysis of monkey feces. The laboratory did not announce that it had newly developed methods, since these really belonged to the client. 

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). 

Three treated cats were sacrificed 0.5, 1, 2, 5, and 10 days after treatment. Radioactivity in urine and feces collected over the 10-day period accounted for 28% and 19% of the applied dose, respectively, but no radioactivity was detected in expired air. Radioactivity in analyzed tissues reached maximal levels at 24 hours (accounting for 8.7% of the applied dose). These data are inadequate for quantitative measurements of the extent of dermal absorption of TOCP, because a significant traction of the applied radioactivity was not accounted for in the analysis, and some of the TOCP may have been ingested by the cats during grooming. 

Various reference materials have been described, to help improving the reliability of trace elemental analysis of lead and other heavy elements, for clinical and environmental applications. Such materials include blood10,11, diets, feces, air filters, dust11, foodstuffs12 and biological tissues13. 

Significantly more phosphorus was excreted in the feces when 1.2% calcium and 1.2% phosphorus diets were fed with either egg white (317 mg) or soy (303 mg), than when any of the other rations were fed. Orthogonal contrast analysis indicated that statistically significant sources of these differences included ration phosphorus level (P <0.001), calcium level (P< 0.0001), and calcium level x protein source (P< 0.0461). The degree of effectiveness of increasing phosphorus excretion with increased ration level of calcium was greater in egg white fed animals than in soy fed animals. 

Urine, feces and food were analyzed for calcium content by atomic absorption spectrophotometry. Data were subjected to statistical analysis by analysis of variance and Duncan s Multiple Range Test. 

There are medical tests to determine whether you have been exposed to chlordecone and/or its breakdown product, chlordecone alcohol. Levels of chlordecone and/or chlordecone alcohol can be measured in blood, saliva, feces, or bile. Chlordecone levels in blood are the best indicator of exposure to chlordecone. Since chlordecone remains in the blood for a long time, the test is useful for a long time after exposure has stopped. Chlordecone can be detected in saliva only within the first 24 hours after exposure therefore, this test has limited use. Blood levels of chlordecone are a good reflection of total body content of chlordecone. However, the test is an unsatisfactory indicator of the amount of chlordecone to which you have been exposed because you cannot be sure how much chlordecone left your body between the time you were exposed and the time the test is performed. These tests cannot predict how your health may be affected after exposure. The tests are not done in routine medical examinations, but doctors can collect body fluid samples and send them to a university medical center or a medical laboratory for analysis. Refer to Chapters 2 and 6 for more information. 

Chlordecone, which is excreted mainly in the feces, appears to undergo enterohepatic recirculation, which limits its excretion (Boylan et al. 1978). Analysis of the amount of chlordecone excreted in the bile compared to the amount found in the stool has indicated that only 5-10% of the bile level of the pesticide is eliminated in the feces (Boylan et al. 1978). Approximately equal fractions of... 

The required data generally are obtained by administering a measured dose of the candidate compound -- often isotopically labelled -- to the rat or mouse either by injection or per os. The animal is housed in a glass metabolism "cage" where it receives food, water, and clean air, and its urine, feces, and respired gases are collected and examined for the parent chemical and its metabolites. Eventual postmortem tissue analysis and calculation of material balance complete the measurements necessary to satisfy the above purposes of metabolism and pharmacokinetic experiments. While in vitro biochemical studies are important adjuncts, it is also apparent that only experiments with intact, healthy, living animals will suffice to meet EPA criteria. 

Birkett AM, Jones GP, Muir JG. 1995. Simple high-performance liquid chromatographic analysis of phenol and/ -cresol in urine and feces. J Chromatogr 674 187-191. 

Heptachlor, heptachlor epoxide, and their metabolites have been measured in urine and feces using GC/ECD (Tashiro and Matsumura 1978). Sample preparation steps involve extraction with acetone and hexane, clean-up on Florisil and silicic acid columns, and extraction of the derivatized metabolites into hexane for GLC analysis. Precision, accuracy, and sensitivity were not reported (Tashiro and Matsumura 1978). 

Ingestion or inhalation of high levels caused severe liver damage, acute renal failure, hemolytic anemia, and disseminated intravascular coagulation in three reported cases. Symptoms from inhalation included anorexia, abdominal pain, vomiting, ecchymoses, and hematuria. In all cases, more than 24 hours elapsed between exposure and onset of symptoms. Because 80-90% of propylene dichloride and its metabolites are eliminated within 24 hours, analysis of blood, urine, and feces for solvent is useless once symptoms appear. ... 

Ticlopidine is metabolized extensively by the liver only trace amounts of intact drug are detected in the urine. Following an oral dose, 60% is recovered in the urine and 23% in the feces. Approximately, 33% of the dose excreted in the feces is intact ticlopidine, possibly excreted in the bile. Approximately 40% to 50% of the metabolites circulating in plasma are covalently bound to plasma proteins, probably by acylation. Although analysis of urine and plasma indicates 20 metabolites or more, no metabolite that accounts for the activity of ticlopidine has been isolated. 

Biological Samples. There were three types of biological samples obtained from workers at the plant urine, whole blood, and feces. All urine and blood samples were internally "spiked" at the factory with 1 yg/mL of a nitrosopiperidine (NPiP) standard. NPiP was used for spiking because it has a similar stability and recovery characteristic to nitrosomorpholine, and to provide a means of gauging the accuracy of the analytical methods. Due to the inability to perform homogeneous mixing on-site, the feces samples were not spiked until they were thawed upon return to the laboratory. Ethyl acetate extracts of urine samples were examined for the presence of N-nitrosodiethanolamine (NDEIA), a metabolite of NMOR, by HPLC-TEA. All samples were immediately frozen at the plant (-80°C) and kept at this temperature until analysis. 

Polybrominated Biphenyls. Rats given a single intravenous dose of " C-2,2, 4,4, 5,5 -hcxabromobiphenyl excreted a cumulative 0.96, 3.3, and 6.6% of the dose in the feces 1, 7, and 42 days after dosing, respectively (Matthews et al. 1977). Only traces (0.1% of the dose) were excreted in the urine. Two decay components were calculated from excretion data an initial decay rate of 1.05% of the dose/day and a later rate of 0.15% of the dose/day. Biliary excretion accounted for 0.68% of the dose between 0 and 4 hours after dosing. Analysis of bile and feces showed that at least 95% of the radioactivity corresponded to the parent compound. Moreover, in rats, 35% of the radioactivity excreted in the bile during the first week after a single dosing was reabsorbed (Tuey and Matthews 1980). 

Methods for the detemination of organobromine compounds such as PBBs and PBDEs generally consist of the following steps extraction of the analyte from the sample matrix clean-up to remove interfering compounds and analysis (separation and quantitation). The primary method of analysis is GC coupled with ECD or MS. Analytical methods have been developed for the determination of PBBs and PBDEs in blood or serum, urine, feces, adipose tissue, liver, and breast milk. The methods for determining PBB and PBDE residues in biological samples are given in Tables 7-1 and 7-2, respectively. 

The distribution of residues of anabolic hormonal-type growth promoters in animal tissues depends on their mode of metabolism and excretion. Residues are commonly found in muscle, fat, liver, kidney, and milk, as well as in urine, bile, and feces. In general, residue concentrations tend to be higher in the excreta than in tissues. Control of the abuse of these compounds is usually carried out through the analysis of edible tissues, injection sites, kidney, fat, urine, or even feces. In recent years, use of fecal samples has become of increasing importance because of their ease of collection in intensive livestock farming. 

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