National Institute for Occupational Safety and Health

“ Samples of urine collected from humans pose a real health risk to laboratory workers who collect and handle these samples. These risks are primarily due to personal contact with infective biological samples and can have serious health consequences, such as infectious hepatitis, and other diseases. There is also some risk from the chemical content of these samples, but this is much less. Those who handle urine specimens should wear protective gloves, and avoid aerosolization of the samples. ”

“ Method 8301 (Hippuric and Methyl Hippuric Acids in urine) is a specific HPLC method and can be used in the presence of xylene, styrene, salicylic acid and aspirin . Other biological monitoring methods include measurement of blood toluene and alveolar air toluene [2] .
NIOSH Manual of Analytical Methods (NMAM) , Fourth Edition, 8/15/94 HIPPURIC ACID IN URINE: METHOD 8300, Issue 2, dated 15 August 1994 - Page 2 of 3 EQUIPMENT:
REAGENTS: 1.
2. 3. 4. 5.
Calibration stock solution, 0.5 g/L. Dissolve 50 mg hippuric acid in 100 mL distilled water. ”

“ In addition to positive interferences from styrene and xylene in the workplace, the ingestion of sodium benzoate in food, salicylic acid, or aspirin by the worker will produce a positive interference. ”