Urine benzene

Total phenol in urine Benzene in exhaled air mixed-exhaled end-exhaled Cadmium Cadmium in urine Cadmium in blood Carbon disulphide 2-Thiothiazolidine-4-carboxylic acid (= TTCA) in urine... 

There is no medical test that shows if you have been exposed to TPH. However, there are methods to determine if you have been exposed to some TPH compounds, fractions, or petroleum products. For example, a breakdown product of n-hexane can be measured in the urine. Benzene can be measured in exhaled air and a metabolite of benzene, phenol, can be measured in urine to show exposure to gasoline or to the TPH fraction containing benzene. Exposure to kerosene or gasoline can be determined by its smell on the breath or clothing. Methods also exist to determine if you have been exposed to other TPH compounds. For example, ethylbenzene can be measured in the blood, urine, breath, and some body tissues of exposed people. However, many of these tests may not be available in your doctor s office. 

ETHYL BENZENE Mandelic acid in urine End of shift at end of 1.5 g/g creatinine Ns... 

Methyl parathion was determined in dog and human serum using a benzene extraction procedure followed by GC/FID detection (Braeckman et al. 1980, 1983 DePotter et al. 1978). An alkali flame FID (nitrogen-phosphorus) detector increased the specificity of FID for the organophosphorus pesticides. The detection limit was in the low ppb (pg/L). In a comparison of rat blood and brain tissue samples analyzed by both GC/FPD and GC/FID, Gabica et al. (1971) found that GC/FPD provided better specificity. The minimum detectable level for both techniques was 3.0 ppb, but GC/FPD was more selective. The EPA-recommended method for analysis of low levels (<0.1 ppm) of methyl parathion in tissue, blood, and urine is GC/FPD for phosphorus (EPA 1980d). Methyl parathion is not thermally stable above 120 °C (Keith and Walters 1985). 

Urine Acidify and heat to hydroloyze add NaOH to pH=11 extract with benzene-diethyl ether reacidify and dry with sodium sulfate derivatize with hexamethyl disilizane on GC column (PNP) GC/ECD 50 pg/L (50 ppb) 95.4 Cranmer 1970 EPA1980d... 

Urine Acidify and heat to hydrolyze add NaOH extract with anhydrous ethyl ether derivatize with diazoethane concentrate add hexane concentrate and cleanup on silica gel elute with benzene-hexane (PNP) GC/ECD 20 pg/L (20 ppb) 85-98 Shafiketal. 1973b... 

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. 

N-Methylformamide in urine Ethyl benzene End of shift 40 mg/g creatinine ... 

The heptafluorobutyric anhydride derivative of pseudoephedrine and electron capture detector have been used to enhance the sensitivity of the gas chromatographic method. Lin and co-workers36 and Cummins and Fourier37 extracted basefied urine or serum with benzene. Heptafluorobutyric anhydride is added to the benzene extract. The heptafluoro-ibutyric anhydride derivative extracted was chromatographed... 

One further compound should be mentioned in this connexion, namely, p-fluorophenylacetic acid (XXII), which has the carbon skeleton of the highly toxic 5-fluoropentanecarboxylic acid (XXIII). It seemed unlikely that (XXII) could be broken down in vivo to fluoroacetic acid, and as expected it was non-toxic. It should be mentioned, however, that aromatic compounds are capable of certain types of oxidative breakdown in the animal body. Jaffe,1 for example, isolated small quantities of muconic acid from the urine of dogs and rabbits which had received considerable quantities of benzene. 

Urine can be tested for the presence of phenol. This test can be used to determine if the urine has a higher than normal concentration of phenol, thus suggesting recent exposure to phenol or to substances that are converted to phenol in the body (e g., benzene). There is no test available that will tell if a person has been exposed only to phenol since many substances are converted to phenol in the body. Because most of the phenol that enters the body is excreted in the urine... 

Human exposure to low levels of phenol is widespread because it is contained in many consumer products including mouthwashes, gargles, tooth drops, throat lozenges, and ointments (Douglas 1972 EPA 1980). Phenol is a normal product of protein metabolism, and it is also a metabolite of benzene. In persons not exposed to phenol or benzene, the total phenol concentration in the urine generally does not exceed 20 mg/L and is usually <10 mg/L (ACGIH 1991). 

Biological monitoring for exposure to phenol is possible by measuring blood or urine levels of the parent compound. However, it should be noted that phenol and metabolites of phenol may also come from other sources. For example, phenol is a metabolite of benzene and of protein metabolism. Urine samples taken from male workers employed in the distillation of high-temperature phenolic fractions of tar revealed a phenol excretion rate of 4.20 mg/hour compared to a control rate of 0.53 mg/hour for non-exposed workers (Bieniek 1994). Samples were taken 4 hours into the workers workday, but the worker exposure levels were not reported. 

The level of phenol detected in blood or urine may not accurately reflect actual phenol exposure because phenol may also appear as a metabolite of benzene or other drugs. It has been shown that under certain acidic conditions used for the hydrolysis of conjugated phenols, acetyl salicylic acid (aspirin) may produce phenol (Baldwin et al. 1981) and yield spuriously higher values for phenol in blood and urine. 

Popp W, Rauscher D, Muller G et al. 1994. Concentrations of benzene in blood and S-phenylmercapturic acid and l, /-muconic acid in urine in car mechanics. Int Arch Occup Environ Health 66 1-6. 

Stommel P, Muller G, Stucker W et al. 1989. Determination of S-phenylmercapturic acid in the urine-An improvement in the biological monitoring of benzene exposure. Carcinogenesis 10 279-282. 

Van Roosmalen PB, Purdham J, Drummond I. 1981. An improved method for the determination of phenol in the urine of workers exposed to benzene or phenol. Int Arch Occup Environ Health 48 159-163. 

Phenyl-mercapturic add Benzene Urine 9h No Traffic, combustion products... 

Hamster urine (dichlorobenzidine, mono- and di-acetyldichloroben-zidine, conjugates) Adjustment of pH, extraction with benzene, volume reduction, formation of heptafluorbutyryl derivatives for conjugates alkaline hydrolysis of aqueous phase followed by derivatization as above. GC/ECD 7-48 g/L No data Bowman and Nony1981 Nony and Bowman 1980 Nony et al. 1980... 

Methods for Determining Biomarkers of Exposure and Effect. Exposure to 1,4-dichloro-benzene may be evaluated by measuring the levels of this compound in blood, breath, milk, and adipose tissue, and by measuring the level of 2,5-dichlorophenol, a metabolite of 1,4-dichlorobenzene, in urine (Bristol et al. 1982 Erickson et al. 1980 Jan 1983 Langhorst and Nestrick 1979 Pellizzari et al. 1985). Sensitive analytical methods are available for measurements in blood. Development of methods with improved specificity and sensitivity for other tissues and breath would be valuable in identifying individuals with low-level exposure. Development of standardized procedures would permit comparison of data and facilitate the study of correlations between exposure and measured levels biological samples. Interlaboratory studies are also needed to provide better performance data for methods currently in use. 

S. Myung, S. Yoon and M. Kim, Analysis of benzene ethylamine derivatives in urine using the programmable dynamic liquid-phase microextraction (LPME) device. Analyst, 2003,128(12), 1443-1446. 

Tests for phenol levels in urine have been used as an index of benzene exposure urinary phenol concentrations of 200mg/l are indica-... 

WalkleyJE, Pagnotto LD, Elkins HB The measurement of phenol in urine as an index of benzene exposure. Am Ind Hyg Assoc 7 22 362-367, 1961... 

Toluene exposure does not result in the hematopoietic effects caused by benzene. The myelotoxic effects previously attributed to toluene are judged by more recent investigations to be the result of concurrent exposure to benzene present as a contaminant in toluene solutions. Most of the toluene absorbed from inhalation is metabolized to benzoic acid, conjugated with glycine in the liver to form hippuric acid, and excreted in the urine. The average amount of hippuric acid excreted in the urine by persons not exposed to toluene is approximately 0.7-1.0 g/1 of urine. ... 

Adjust the urine to pH 7 with 0.1 M HC1 or 0.1 M NaOH. Extract 3 times with 2 mL of benzene, centrifuging between each extraction. 

To circumvent this bioactivation pathway, a more easily oxidizable C-H bond can be included in the molecule, such as a benzylic methyl group. Thus, toluene, is significantly less toxic than benzene since its major CYP metabolite is benzyl alcohol, which is converted to benzoic acid by ALDH. Benzoic acid is conjugated with glycine and eliminated in the urine as hippuric acid, which is much less toxic than the metabolites of benzene... 

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