National Institute for Occupational Safety and Health

“ Sodium trichloroacetate was used instead of trichloroacetic acid for all phases of this method development as well as in the preparation of standards. Trichloroacetic acid is very hygroscopic; the salt is much less so. 12.
Prepare working (calibration) standards by serial dilution to cover the analytical range. A suggested working standard concentration range is 0.08 to 300 μg/mL. Withdraw 200 μL of each calibration standard and follow steps 4 through 10. 13. ”

“ There are numerous literature methods for the determination of TCAA in urine [13] . The National Center for Environmental Health/Centers for Disease Control and Prevention (NCEH/CDC) has a method that is more expensive but also significantly more sensitive [11] . This method is based on the procedure used by O’Donnell [7] with some modifications. NIOSH Manual of Analytical Methods (NMAM) , Fifth Edition TRICHLOROACETIC ACID IN URINE: METHOD 8322, Issue 1, dated 17 April 2015 - Page 2 of 5
REAGENTS:
EQUIPMENT:
1.
Sodium trichloroacetate [CAS #650-51-1] , 97% purity or greater* 2. ”

“ Calibrate daily with at least six liquid working standards covering the expected concentration range of the samples. MEASUREMENT: PRECAUTION: SYRINGE-RINSE SOLUTIONS: Toluene will extract material from some urine specimens that may eventually clog the syringe and cause injection errors unless the syringe is rinsed with the following solutions following each injection. ”