Hippo acid and methyl hippo acid from urine
Hippoic acid from urine (HIPP HPPCR) and methylhippoic acid (METHIP) from urine can be requested by the occupational physician as a result of the RI&E, because there is a risk associated with the work.
Among other things, hippuric acid is a metabolite of toluene and is correspondingly more frequently excreted in the urine upon exposure to toluene. Because of the physiological occurrence of hippuric acid, the determination of cresol in urine is more appropriate for assessing exposure to toluene.
Methylhippuric acids are metabolites of their corresponding xylenes (o-, m-, p-). Xylene is a volatile aromatic hydrocarbon and belongs to the "BTXE" group (benzene-toluene-xylene-ethylbenzene). Xylenes are used as solvents and are used in the manufacture of plastics and adhesives. They are also added to fuels to increase the octane number. Xylenes are harmful to health when absorbed through the skin and respiratory tract. For example, they can cause headaches, memory and orientation disorders, dizziness and shortness of breath.