Effect of Pre-Analytical Conditions on Salivary Nitrite Levels


The aim of the present paper was to analyze the influence of sampling and storage procedures on nitrite con- centration values in the saliva of healthy persons. The samples were obtained and stored under varied condi- tions, and processed using the Griess method. Results: when the salivary nitrite concentration was measured immediately after collection a significant dependence on the collection time was observed. A mean value of 94 µmol/L (range 3 - 625) was obtained at 8:30 am. This value decreased significantly with time (p < 0.05) reaching a value of 68 at 12:30 noon. Concerning the sample storage, a significant increase in the nitrite concentration was observed after 2 hrs, either at 4?C or at room temperature (p < 0.05). In spite of the high variability between individuals the values for each individual showed a marked constancy independent of the sampling day. According to our results, by controlling pre-analytical parameters, principally sampling and storage procedures, reproducibility is improved.

Share and Cite:

R. Morelatto, T. Benavidez, A. Baruzzi, V. Solís and S. Blanc, "Effect of Pre-Analytical Conditions on Salivary Nitrite Levels," American Journal of Analytical Chemistry, Vol. 2 No. 6, 2011, pp. 683-688. doi: 10.4236/ajac.2011.26078.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] P. N. Magee, “The Experimental Basis for the Role of Ni- troso Compounds in Human Cancer,” Cancer Surveys, Vol. 8, 1989, pp. 207-239.
[2] P. E. Hartman, “Review: Putative Mutagens and Carcino- gens in Foods. I. Nitrate/Nitrite Ingestion and Gastric Cancer Mortality,” Environmental Mutagenesis, Vol. 5, No. 1, 1983, pp. 111-121. doi:10.1002/em.2860050112
[3] S. S. Mirvish, “Role of N-Nitroso Compounds (NOC) and N-Nitrosation in Etiology of Gastric, Esophageal, Nasopharyngeal and Bladder Cancer and Contribution to Cancer of Known Exposures to NOC,” Cancer Letters, Vol. 93, No. 1, June 1995, pp. 17-48. doi:10.1016/0304-3835(95)03786-V
[4] M. Rogers, T. Vaughan, S. Davis and D. Thomas, “Con- sumption of Nitrate, Nitrite and Nitrosodimethylamine and the Risk of Upper Aerodigestive Tract Cancer,” Cancer Epidemiology, Biomarkers & Prevention, Vol. 4, No. 1, January 1995, pp. 29-36.
[5] B. Spiegelhalder, G. Einsenbrand and R. Preussman, “In- fluence of Dietary Nitrate on Nitrite Content of Human Saliva: Possible Relevance in Vivo Formation of N-Ni- troso Compounds,” Food and Cosmetics Toxicology, Vol. 14, No.6, 1976, pp. 545-548. doi:10.1016/S0015-6264(76)80005-3
[6] C. L. Walters, R. J. Hart and P. L. Smith, “Analysis of Total N-Nitroso Compounds as a Group by Denitrosation to Nitric Oxide, with Detection Using a Chemilumines-cence Analyzer,” IARC Scientific Publication, 1983, pp. 295-308.
[7] D. Forman, S. Al-Dabbagh and R. Doll, “Nitrates, Nitrites and Gastric Cancer in Great Britain,” Nature, Vol. 313, February 1985, pp. 620-625. doi:10.1038/313620a0
[8] A. S. Pannala, A. R. Mani and J. P. Spencer, “The Effect of Dietary Nitrate on Salivary, Plasma, and Urinary Nitrate Metabolism in Humans,” Free Radical Biology and Medi-cine, Vol. 34, No. 5, March 2003, pp. 576-584. doi:10.1016/S0891-5849(02)01353-9
[9] P. J. R. Phizackerley and A. S. Al-Dabbagh, “The Esti-mation of Nitrate and Nitrite in Saliva and Urine,” Ana-lytical Biochemistry, Vol. 131, No. 1, May 1983, pp. 242-245. doi:10.1016/0003-2697(83)90161-6
[10] Y. Tanaka, N. Naruishi, H. Fukuya, J.Sakata, K. Saito and S. Wakida, “Simultaneous Determination of Nitrite, Nitrate, Thiocyanate and Uric Acid in Human Saliva by Capillary Zone Electrophoresis and Its Application to the Study of Daily Variations,” Journal of Chromatography, A, Vol. 1051, No. 1-2, July 2004, pp. 193-197.
[11] H. Li, C. Duncan and J. Townend, “Nitrate-Reducing Bacteria on Rat Tongues,” Applied and Environmental Microbiology, Vol. 63, No. 3, March 1997, pp. 924-930.
[12] S. Chiappin, G. Antonelli, R. Gatti and E. F. De Palo, “Saliva Specimen: A New Laboratory Tool for Diagnostic and Basic Investigation,” Clinica Chimica Acta, Vol. 383, No. 1-2, April 2007, pp. 30-40. doi:10.1016/j.cca.2007.04.011
[13] J. Xu, X. Xu and W. Verstraete, “Quantitative Measure- ment of the Nitrate Reductase Activity in the Human Oral Cavity,” Food and Chemical Toxicology, Vol. 39, No. 4, 2001, pp. 393-400. doi:10.1016/S0278-6915(00)00150-2
[14] D. Boji?, V. Aleksandar, L. J. Boji? and J. M. Perovi?, “The Effects of Dietary Nitrate, Ph and Temperature on Nitrate Reduction in the Human Oral Cavity,” Physics, Chemistry and Technology, Vol. 3, No. 1, May 2004, pp. 53-60.
[15] S. S. Mirvish, K. J. Reimers and B. Kutler, “Nitrate and Nitrite Concentrations in Human Saliva for Men and Wo- men at Different Ages and Times of the Day and Their Consistency over Time,” European Journal of Cancer Prevention, Vol. 9, No. 5, October 2000, pp. 335-342. doi:10.1097/00008469-200010000-00008
[16] B. S. Yu ,P. Chen, L. H. Ni and S. Z. Yao, “Simultaneous Determination of Nitrate and Nitrite in Saliva and Food- Stuffs by Non-Suppressed Ion Chromatography with Bulk Acoustic Wave Detector,” Analitycal Sciences, Vol. 17, No. 4, April 2001, pp. 495-498. doi:10.2116/analsci.17.495
[17] V. Mori and M. Bertotti, “Amperometric Detection with Microelectrodes in FIA: Studies on the Conversion of Ni- trate to Nitrite in Human Saliva,” Analytical Letters, Vol. 32, No. 1, 1999, pp. 25-37. doi:10.1080/00032719908542596
[18] P. M. J. Bos, P. A. Van Den Brandt, M. Bedel and T. H. Ockhuizen, “The Reproducibility of the Conversion of Nitrate and Nitrite in Human Saliva after a Nitrate Load,” Food and Chemical Toxicology, Vol. 26, No. 2, 1988, pp. 93-97. doi:10.1016/0278-6915(88)90104-4
[19] A. F. Badawi, G. Hosny, M. El-Hadary and M. H. Mostaf, “Salivary Nitrate, Nitrite and Nitrate Reductase Activity in Relation to Risk of Oral Cancer in Egypt,” Disease Markers, Vol. 14, No. 2, January 1998, pp. 91-97.
[20] J. Van Maanen, D. Pachen, M. Dallinga and J. Kleinjans, “Formation of Nitrosamines during Consumption of Ni-trate and Amine-Rich Foods, and the Influence of the Use of Mouthwashes,” Cancer Detection and Prevention, Vol. 22, No. 3, 1998, pp. 204-212. doi:10.1046/j.1525-1500.1998.0oa26.x

Copyright © 2022 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.