Urine 2,4-dinitrophenol

The method was applied for the determination of 2,4-dinitrophenol in urine. The reproducibility was very good. The results obtained by the proposed method also agreed well with the values obtained by standard methods. 

In the only study that measured 1,3-DNB metabolite production in humans after dermal exposure, the total production of both amino and nitro metabolites in urine was reported using 2,4-dinitrophenol as a standard (Ishihara et al. 1976). The results indicate that 1,3-DNB (in solution) rapidly penetrated skin and was also rapidly converted and excreted in urine. A maximum amount of amino and nitro metabolites was reached within the first hour after exposure and returned to normal levels after 10 hours. The limitations of this study are a small sample size (one person) and no detailed information on the nature of 1,3-DNB metabolites. 

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. 

Methods for Determining Biomarkers of Exposure and Effect. No biomarker has been identified that can be quantitatively related to dinitrophenol exposure (see Section 2.5.1) however, the presence and the amount of 2,4-DNP and 2-amino-4-nitrophenol, a metabolite in the urine, can be used as rough indicators of the intensity of exposure (see Section 2.5.1). The methods presently available for determining 2,4-DNP and 2-amino-4-nitrophenol (diazotization) in urine are outdated (Gisclard and Woodward 1946). An enzyme-linked immunosorbent assay (ELISA) is available for the quantitation of 2-amino-4-nitrophenol in water samples, but is not effective in urine (Li et al. 1991). It would be useful to develop an updated routine method for determining 2,4-DNP, 2-amino-4-nitrophenol, and 4-amino-2-nitrophenol in urine with well-defined detection limits, precision, and accuracy. 

Toxic substances. Among other toxic substances, several nitrocompounds and nitrosamines have been determined in the blood and urine of individuals exposed to such toxic substances. As an example, the determination of 2,4-dinitrophenol< ) in the urine of humans working in the production of picric acid can be mentioned. 

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