Page:NIOSH Manual of Analytical Methods - 2560.pdf/4

 1-NITR OP YRE NE: M ETH OD 2560, Issue 1, dated 1 5 Ma rch 2003 - Page 4 of 5 The method LOD and LOQ as determined using spiked media samples were 3.4 ng/sample and 11.5 ng/sample respectively. However, because the detector was operating at its m ax im um sen sitivity settings, the normal baseline noise at th e lowe st analyte levels often m ade the peak d ifficult to be pro perly integrated. Therefore, more realistic and repeatable values for the LOD and LOQ are 10 and 20 ng/sa m ple respectively. Average recoveries of 1-nitropyrene from spiked glass fiber filters ranged from 88.4% to 101.2% for an alyte quantities of 1.0 to 50.0 :g/filter using liquid standards as the spiking solution. Recovery of 1-nitropyrene from NIST SRM-1650 Diesel Particulates weighed on glass fiber filters and carried through the extraction and sam ple preparation process yielded recoveries of 73% to 114% (see NOTE) for sample quantities of 1.63 mg to 26.6 mg. A thirty day storage stability study of 1-nitropyrene spiked on glass fiber filters indicates that the recovery of the analyte at a level of 10 :g/filter is 102%. The samples were stored in a closed cardboard container at room tem pera ture fo r the duration of th e study.

NOTE: The rated concentration of the NIST SRM -1650 for 1-Nitropyrene is 19+2 ug/g diesel particulate. The unc ertainty in the am ount is +10.5%. This accounts for the wide range of recoveries of the NIST standard, particularly at the low am ounts used in the recovery studies which were used to mim ic the real world samples.

REFERENCES: [1] [2] [3] [4]

IARC [1984]. 1-Nitropyrene. IARC M onograph on Evaluation of Cancer Risk of Chem icals to Humans, 33:209-22, Apr. IARC [1997]. 1-Nitropyrene. IARC M onograph on Evaluation of Cancer Risk of Chem icals to Humans, 46:321 -358, Apr. NIST [1991]. “Certificate of Analysis.” Standard R eference Material 1650, Diesel Particulate Matter. Gaithersburg, MD: National Institute of Standards and Technology, Decem ber 12. Jaycox LB [2002]. Backup Data Report, 1-Nitropyrene. Cincinnati, OH: National Institute for Occupational Safety and He alth, DART. (unpublished report).

METHOD WRITTEN BY: Larry B. Jaycox, Ph.D., NIOSH/DART

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition