Hippuric acid urinary levels

Samples of your urine can be tested for the presence of cresols, although this test is not routinely available in hospitals and clinics. This test will not tell you whether or not you will have any adverse health effects. The urine sample would have to be taken within 1 day of your exposure to be valid. Because cresols occur naturally in people, ant at levels that very from one individual to the next, results from tests for cresol exposure should be compared to values obtained from the same individual either before exposure or several days after exposure. Small changes might be caused by variation in daily diet. You should also be aware that an increased presence of cresols in the urine could indicate exposure to toluene, a related compound, rather than cresols. However, toluene exposure would also result in elevated urinary levels of hippuric acid cresol exposure would not. 

The influence of dose size was also examined in male and female B6C3Fi mice given 0, 10, 100, 1000, 5000, 15 000 or 30 000 ppm (mg/kg diet) ciimamyl anthranilate in the diet for four days (Caldwell et al., 1985). The urinary excretion of cinnamyl anthranilate, hippuric acid and anthranilic acid within 24-h after removal of the test diet rose with increasing cinnamyl anthranilate dose. Cinnamyl anthranilate was detected in increasing quantities in the urine of male mice at 1000 ppm and above. In females, it was only seen at 5000 ppm and above and the levels were two- to nine-fold lower. 

When Wistar rats were exposed to 50, 300 or 600 ppm [0.22, 1.30 and 2.60 g/m ] ethylbenzene intermittently for up to 16 weeks, the urinary recovery of metabolites increased with dose but not linearly. The metabolic pattern of ethylbenzene was affected by exposure level but not by the duration of administration. The amounts of 1-phenylethanol and -hydroxyacetophenone increased with increasing exposure, but those of phenylglyoxylic acid and hippuric acid decreased (Engstrdm et al, 1985). 

Interestingly, the number of examples of toxicity biomarkers discovered using nuclear magnetic resonance (NMR)-based and MS-based metabonomics is quite impressive. In metabonomics studies in which a severe toxicity is observed, almost always the relative urinary concentrations of Krebs cycle intermediates are decreased and a concomitant decrease in urinary levels of hippuric acid is observed. These compounds have been proposed to be nonspecific markers of toxicity as they reflect a combination of complex changes in an organism [11,48-51], Taurine has been known to be a specific marker for liver toxicity as its urinary levels are typically increased with necrosis and fatty liver. Several bile acids in the serum such as cholic, glycolic, and taurocholic acids have also been demonstrated to be sensitive markers of liver dysfunction [50], In the literature, there are a few preclinical and clinical examples of... 

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