Urine analysis, monitoring exposure

During refueling, the respective concentrations were 1.64, 1.33, 0.78, 0.19, and 6.34 mBq/m3 (44.3, 35.9, 21,5.1, and 171 fCi/m3). The derived air concentration recommended by the ICRP for occupational exposure is 80.0 mBq/m3 (2,200 fCi/m3). In 1997, the French radiation protection office conducted monitoring (24-hour urine analysis/whole body activity measurements) of workers in the non-nuclear energy field (i.e., nuclear medicine, research laboratories, and non-nuclear industries) to ascertain the occupational intake of radionuclides (De Vathaire et al. 1998). 241Am was not detected in samples from any of the 37 workers who worked with the isotope. 

It is plausible that analysis of urine samples may be used to monitor exposure to aromatic amines. In a model experiment, rats were treated with 2,4-diaminoanisole (2,4-DAA) and the urine analyzed for the amine and its most important metabolites (33). The results are shown in Table II. For the two doses used in this study, the major metabolite is 4-acetamido-2-aminoanisole, indicating that this compound may be used to monitor occupational exposure to 2,4-DAA. 

Kawai, T., Yasugi. T., Horiguchi, S., Uchida, Y, Iwami, O., Iguchi, H., Inoue, O., Watanabe, T., Nakatsuka, H. Ikeda, M. (1990) Biological monitoring of occupational exposure to isopropyl alcohol vapour by urine analysis for acetone. Int. Arch, occup. environ. Health, 62, 409-413... 

B. Bocca, A. Alimonti, A. Cristaudo, E. Cristallini, F. Petrucci, S. Caroli, Monitoring of the exposure to platinum-group elements for two Italian population groups through urine analysis, Anal. Chim. Acta, 512 (2004), 19 D25. 

Murray. W, J,. and Franklin. C. A. (1992), Monitoring for exposure 10 amieholinescerase-inhibiiing organophosphonis and carbamate compounds by urine analysis. In Clinical and Experimeniai Toxicology of Organophospluiles and Carbamates (B, Ballantyne, and T, C. Marrs, eds,), Butterworth-Heinemann, London,... 

Applicators and residents of dichlorvos (DDVP) treated structures were monitored for evidence of insecticide exposure using exposure pads, air samplers, serum and red blood cell acetylcholinesterase (AChE) tests, and urine analysis. There was no evidence of DDVP or dichloroacetic acid (DCAA) in the urine of applicators or cooperators. There were slight but significant differences (Pi0.05) in serum AChE activity of residents of treated units, but erythrocyte AChE was unchanged. Applicator AChE test results were inconclusive. It was concluded that there was not a significant risk. In terms of acute toxicity, to either the pesticide applicators or the residents of treated structures. 

The biological monitoring of solvents emitted from paints or varnishes on humans is not well developed. In two studies,solvents from paints and varnishes were determined in blood, urine and internal breath. Blood and urine analysis is less sensitive than internal breath measurements. This was carried out in a study on exposure to paints in aircraft maintenance. ... 

Table 17.1 depicts nine reports on findings of increased lung cancer incidences and mortdities in both battery and smelter workers with elevated Pb exposures and one report derived from Pb exposure monitoring analysis. These cohorts and other subjects were from Britain, Finland, Italy, Sweden, and the United States. Pb exposures were indexed by actual environmental measurements in air or measurements of Pb in blood and urine. A job-exposure matrix approach was employed in part of one study using a nested case—control approach. 

For the majority of inorganic compounds the most important route of excretion is via the urine, and urinary concentrations may be used to monitor exposure. Some metals (manganese is an example) are excreted predominantly into the bile and then excreted into the gut to appear finally in the faeces. Toxicologists seldom rely on faecal analysis to monitor exposure, for reasons which should be apparent to all. 

Vesterberg, 0, Astrand 1. 1976. Exposure to trichloroethylene monitored by analysis of metabolites in blood and urine. J Occup Med 18 224. 

As with urine, saliva (spumm) is easy to collect. The levels of protein and lipids in saliva or spumm are low (compared to blood samples). These matrices are viscous, which is why extraction efficiency of xenobioties amoimts to only 5 to 9%. By acidifying the samples, extraction efficiencies are improved as the samples are clarified, and proteinaceous material and cellular debris are precipitated and removed. Some xenobioties and their metabohtes are expressed in hair. Hair is an ideal matrix for extraction of analytes to nonpolar phases, especially when the parent xenobioties are extensively metabolized and often nondetectable in other tissues (parent molecules of xenobioties are usually less polar than metabolites). Hair is a popular target for forensic purposes and to monitor drug compliance and abuse. Human milk may be an indicator of exposure of a newborn to compounds to which the mother has been previously exposed. The main components of human milk are water (88%), proteins (3%), lipids (3%), and carbohydrates in the form of lactose (6%). At present, increasing attention is devoted to the determination of xenobioties in breath. This matrix, however, contains only volatile substances, whose analysis is not related to PLC applications. 

C.P. Weisskopf and J.N. Seiber, New approaches to the analysis of organophosphate metabolites in the urine of field workers, in ACS Symposium Series Biological Monitoring for Pesticide Exposure Measurement, Estimation, and Risk Reduction, eds. R.G.M. Wang, C.A. Franklin, R.C. Honeycutt, and J.C. Reinert, American Chemical Society, Washington, DC, pp. 206-214 (1989). 

Unchanged compounds or metabolites in blood and urine can be used to monitor human exposure to some carbamates. Table 5 shows some biological indices of internal dose used to monitor carbamate exposure. Urine carbamate metabolites may provide a good estimate of the internal dose because the half-life of most compounds is very short, samples collected soon after the end of the exposure are preferable for analysis (WHO, 1986). 

Ong CN, Chia SE, Phoon WH, et ah Monitoring of exposure to cyclohexanone through the analysis of breath and urine. ScandJ Work Environ Health 17 430-435, 1991... 

Monitoring human exposure to fluoride can be accomplished with varying degrees of accuracy through the analysis of several biological fluids and tissues. The concentrations of fluoride in plasma, serum and urine have been considered... 

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). 

In the case of pesticides which are not ChE inhibitors, exposure is measured by the analysis of blood and/or urine for the active ingredient or its metabolites. Baseline levels of pesticides and/or metabolites are not usually determined, with the exception of methyl bromide. In this case, a blood sample is taken to check for bromide ion before fumigators use the pesticide. Blood and urine tests are run only in the case of spills or other accidents to assist in identifying the cause of poisoning or to monitor workers in a workplace. Paraquat, chlorinated hydrocarbons, mercury, p-nitrophenol, and dinitrophenol are examples of pesticides or metabolites of pesticides that have been found in the urine of exposed workers. 

Sheldon L, Umana M, Bursey J, et al. 1986. Biological monitoring techniques for human exposure to industrial chemicals Analysis of human fat, skin, nails, hair, blood, urine, and breath. Park Ridge, NJ Noyes Publications, 86-122. 

The two major kinds of samples analyzed for xenobiotics exposure are blood and urine. Both of these sample types are analyzed for systemic xenobiotics, which are those that are transported in the body and metabolized in various tissues. Xenobiotic substances, their metabolites, and then-adducts are absorbed into the body and transported through it in the bloodstream. Therefore, blood is of unique importance as a sample for biological monitoring. Blood is not a simple sample to process, and subjects often object to the process of taking it. Upon collection, blood may be treated with an anticoagulant, usually a salt of ethylenediaminetetraacetic acid (EDTA), and processed for analysis as whole blood. It may also be allowed to clot and be centrifuged to remove solids the liquid remaining is blood serum. 

Exposure. Because DEHP is rapidly metabolized and excreted, it is difficult to monitor anything but recent human exposures through the body fluids. MEHP and several oxidized MEHP metabolites can be measured in blood and urine and are biomarkers of exposure, and DEHP has been detected in human milk. Since DEHP is a lipophilic substance, it has the potential to deposit in adipose tissues. More chronic exposures can be detected with a fat biopsy, but there are no validated approaches for assessment of chronic exposure by fat biopsy analysis. Additional studies of methods for monitoring DEHP exposure would be of value. 

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