NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.

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S2
Pagana, Kathleen D. & Pagana, Timothy J. (2001). Mosby’s Diagnostic and Laboratory Test Reference 5th Edition: Mosby, Inc., Saint Louis, MO.

S3
Porphyrins, Blood and Serum [3 paragraphs]. ARUP’s Guide to Clinical Laboratory Testing [On-line information]. Available FTP: http://www.arup-lab.com/guides/clt/tests/clt_143b.jsp#1145040

S4
(2000 May 19, Revised). The Interaction of Iron and Erythropoietin [17 paragraphs]. Information Center for Sickle Cell and Thalassemic Disorders [On-line information]. Available FTP: http://sickle.bwh.harvard.edu/iron_epo.html

S5
Iron Metabolism Disorders [21 paragraphs]. ZPP Hematofluorometer. AVIV Biomedical [On-line information]. Available FTP: http://www.avivbiomedical.com/Pages/IRON%20METAB.html

S6
Staudinger, K. and Roth, V. (1998 February 15). Occupational Lead Poisoning [ paragraphs]. American Family Physician [On-line journal]. Available FTP: http://www.aafp.org/afp/980215ap/stauding.html

S7
Labbe, R., et. al. (1987). Zinc protoporphyrin. Past, present, and future [1 paragraph]. Annals of the New York Academy of Sciences, vol 514 (1) [Abstract]. Available FTP: http://www.annalsnyas.org/cgi/content/abstract/514/1/7

S8
Mei, Z., et. al. (2003). Erythrocyte protoporphyrin or hemoglobin: which is a better screening test for iron deficiency in children and women? [25 paragraphs]. American Society for Clinical Nutrition, AM J Clin Nutr 2003;77:1229-33 [On-line information]. Available online as PDF

S9
Roh, Y., et. al. (2000). Zinc Protoporphyrin IX Concentrations between Normal Adults and the Lead-Exposed Workers Measured by HPLC, Spectrofluorometer, and Hematofluorometer [40 paragraphs]. Industrial Health 2000, 38, 372-379. [On-line journal]. Available FTP: http://www.niih.go.jp/en/indu_hel/2000/pdf/IH38_48.pdf

S10
The Heme Biosynthetic Pathway [22 paragraphs]. The Merck Manual of Diagnosis and Therapy. [On-line information]. Available FTP: http://www.merck.com/mrkshared/mmanual/section2/chapter14/14a.jsp

S11
Lead Poisoning [18 paragraphs]. The Merck Manual of Diagnosis and Therapy. [On-line information]. Available FTP: http://www.merck.com/mrkshared/mmanual/section19/chapter263/263b.jsp

S12
DiGuiseppi, C. (1996). Guide to Clinical Preventive Services, Second Edition Metabolic, Nutritional, and Environmental Disorders Screening for Elevated Lead Levels in Childhood and Pregnancy, Recommendation [ paragraphs]. U.S. Preventive Services Task Force. Guide to Clinical Preventive Services, 2nd Edition. Washington, DC: U.S. Department of Health and Human Services, Office of Disease Prevention and Health Promotion, 1996. [On-line information]. Available FTP: http://cpmcnet.columbia.edu/texts/gcps/gcps0033.html

S13
(60 FR 52856, Oct. 11, 1995; 63 FR 1152, Jan. 8, 1998) Regulations (Standards - 29 CFR), Employee standard summary - 1910.1025 App B [48 paragraphs]. U.S. Department of Labor, Occupational Safety & Health Administration (OSHA) [Current on-line Regulation Standard for Lead Exposure]. Available online

S14
(57 FR 26627, May 4, 1993, as amended at 58 FR 34218, June 24, 1993). Regulations (Standards - 29 CFR), Medical Surveillance Guidelines - 1926.62 App C [ paragraphs]. U.S. Department of Labor, Occupational Safety & Health Administration (OSHA) [Current on-line Regulation Standard for Lead Exposure]. Available online

S15
Labbe, R., et. al. (1999). Observations on the Zinc Protoporphyrin/Heme Ratio in Whole Blood [11 paragraphs]. Clinical Chemistry, Technical Briefs 45:146-148 [On-line journal]. Available FTP: http://www.clinchem.org/cgi/content/full/45/1/146

S16
Labbe, R., et. al. (1999). Zinc Protoporphyrin: A Metabolite with a Mission [55 paragraphs]. Clinical Chemistry 45:2060-2072 [On-line journal]. Available FTP: http://www.clinchem.org/cgi/content/full/45/12/2060

S17
CDC: Preventing Lead Poisoning in Young Children

S18
Wu, A. (2006). Tietz Clinical Guide to Laboratory Tests, Fourth Edition. Saunders Elsevier, St. Louis, Missouri. Pp 1154-1156.

S19
(1993 June 24, Amended). Regulations (Standards - 29 CFR) Medical Surveillance Guidelines - 1926.62 App C [ 79 paragraphs]. OSHA (Occupational Safety & Health Administration Medical Surveillance Guidelines [On-line information]. Accessed on: 8/16/07. Available FTP: http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10644

S20
(2006 July). Comparative Effectiveness of Zinc Protoporphyrin and Hemoglobin Concentrations in Identifying Iron Deficiency in a Group of Low-Income, Preschool-Aged Children: Practical Implications of Recent Illness [39 paragraphs]. Pediatrics v118(1). [On-line information]. Accessed on: 8/18/07. Available FTP: http://pediatrics.aappublications.org/cgi/content/abstract/118/1/224

S21
Rettmer, R. et. al., (1999 September 3). Zinc Protoporphyrin/Heme Ratio for Diagnosis of Preanemic Iron Deficiency [30 paragraphs]. Pediatrics v104 (3). [On-line information]. Accessed on: 8/16/07. Available FTP: http://pediatrics.aappublications.org/cgi/content/full/104/3/e37

S22
(© 2007). Zinc Protoporphyrin (ZPP), Whole Blood [7 paragraphs]. ARUP’s Laboratory Test Directory [On-line information]. Accessed on: 8/18/07. Available FTP: http://www.aruplab.com/guides/ug/tests/0020605.jsp

S23
(© 2007). Protoporphyrin, Free Erythrocyte, and Zinc Protoporphyrin [6 paragraph]. LabCorp Test Information [On-line information]. Accessed on: 8/18/07. Available FTP: http://www.labcorp.com/datasets/labcorp/html/chapter/mono/bm007100.htm

S24
Dombeck TA and Satonik RC. The Porphyrias. Emergency Medicine Clinics of North America. Volume 23, Issue 3, Pages 885-899.

S25
Arup Laboratories. Test Directory: Zinc Protoporphyrin (online information, accessed October 2007). Available online: http://www.aruplab.com/guides/ug/tests/0020605.jsp

S26
Quest Diagnostics. Test Menus: Zinc Protoporphyrin (online information, accessed October 2007). Available online