title: Association of arsenic and metals with concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D among adolescents in Torreón, Mexico.
abstract: BACKGROUND
  Limited data suggest that lead (Pb), cadmium (Cd), and uranium (U) may disrupt vitamin D metabolism and inhibit production of 1,25-dihydroxyvitamin D [1,25(OH)2D], the active vitamin D metabolite, from 25-hydroxyvitamin D [25(OH)D] in the kidney.
  
  
  OBJECTIVE
  We evaluated the association between blood lead (BPb) and urine arsenic (As), Cd, molybdenum (Mo), thallium (Tl), and U with markers of vitamin D metabolism [25(OH)D and 1,25(OH)2D].
  
  
  METHODS
  We conducted a cross-sectional study of 512 adolescents in Torreón, a town in Mexico with a Pb smelter near residential areas. BPb was measured using atomic absorption spectrometry. Urine As, Cd, Mo, Tl, and U were measured using inductively coupled plasma mass spectrometry. Serum 25(OH)D and 1,25(OH)2D were measured using a chemiluminescent immunoassay and a radioimmunoassay, respectively. Multivariable linear models with vitamin D markers as the outcome were used to estimate associations of BPb and creatinine-corrected urine As and metal concentrations with serum vitamin D concentrations, controlling for age, sex, adiposity, smoking, socioeconomic status, and time outdoors.
  
  
  RESULTS
  Serum 25(OH)D was positively associated with urine Mo and Tl [1.5 (95% CI: 0.4, 2.6) and 1.2 (95% CI: 0.3, 2.1) ng/mL higher with a doubling of exposure, respectively]. Serum 1,25(OH)2D was positively associated with urine As and U [3.4 (95% CI: 0.9, 5.9) and 2.2 (95% CI: 0.7, 3.7) pg/mL higher, respectively], with little change in associations after additional adjustment for serum 25(OH)D. Pb and Cd were not associated with 25(OH)D or 1,25(OH)2D concentrations.
  
  
  CONCLUSIONS
  Overall, our findings did not support a negative effect of As or metal exposures on serum 1,25(OH)2D concentrations. Additional research is needed to confirm positive associations between serum 1,25(OH)2D and urine U and As concentrations and to clarify potential underlying mechanisms.
authors.affiliation: Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.
authors.forename: Rachel D
authors.initials: RD
authors.lastname: Zamoiski
authors.forename: Eliseo
authors.initials: E
authors.lastname: Guallar
authors.forename: Gonzalo G
authors.initials: GG
authors.lastname: García-Vargas
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Rothenberg
authors.forename: Carol
authors.initials: C
authors.lastname: Resnick
authors.forename: Marisela Rubio
authors.initials: MR
authors.lastname: Andrade
authors.forename: Amy J
authors.initials: AJ
authors.lastname: Steuerwald
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Parsons
authors.forename: Virginia M
authors.initials: VM
authors.lastname: Weaver
authors.forename: Ana
authors.initials: A
authors.lastname: Navas-Acien
authors.forename: Ellen K
authors.initials: EK
authors.lastname: Silbergeld
mesh_terms: D000293:Adolescent; D001151:Arsenic / Q000378:metabolism* / Q000633:toxicity / Q000652:urine; D002648:Child; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007854:Lead / Q000097:blood / Q000633:toxicity; D008297:Male; D008670:Metals / Q000378:metabolism* / Q000633:toxicity; D008800:Mexico; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*
chemical_list: D008670:Metals; D014807:Vitamin D; D007854:Lead; C097949:1,25-dihydroxyvitamin D; C104450:25-hydroxyvitamin D; D001151:Arsenic
references.citation: Salud Publica Mex. 1998 Mar-Apr;40(2):133-40
references.pmid: 9617194
references.citation: Am J Clin Nutr. 2004 Dec;80(6 Suppl):1689S-96S
references.pmid: 15585789
references.citation: J Natl Cancer Inst. 2006 Apr 5;98(7):451-9
references.pmid: 16595781
references.citation: Eur J Clin Nutr. 1999 Dec;53(12):920-6
references.pmid: 10602348
references.citation: Environ Health Perspect. 2007 Apr;115(4):630-5
references.pmid: 17450235
references.citation: N Engl J Med. 2007 Jul 19;357(3):266-81
references.pmid: 17634462
references.citation: Biochim Biophys Acta. 2007 Feb;1770(2):266-72
references.pmid: 17118558
references.citation: Chemosphere. 2011 Apr;83(3):211-25
references.pmid: 21216433
references.citation: Environ Health Perspect. 1999 Apr;107(4):279-84
references.pmid: 10090706
references.citation: Toxicology. 2002 Dec 27;181-182:71-8
references.pmid: 12505287
references.citation: Nephron. 1996;72(2):313-7
references.pmid: 8684547
references.citation: N Engl J Med. 1988 Sep 29;319(13):845-9
references.pmid: 2842681
references.citation: J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):473-6
references.pmid: 17197173
references.citation: Environ Pollut. 1993;80(1):91-4
references.pmid: 15091878
references.citation: Int Arch Occup Environ Health. 1990;62(3):189-93
references.pmid: 2347639
references.citation: Am J Clin Nutr. 2004 Mar;79(3):362-71
references.pmid: 14985208
references.citation: Arch Environ Health. 2003 Mar;58(3):172-83
references.pmid: 14535578
references.citation: J Expo Sci Environ Epidemiol. 2014 Nov;24(6):634-42
references.pmid: 24549228
references.citation: Environ Res. 2011 Jan;111(1):110-8
references.pmid: 21093857
references.citation: Reprod Toxicol. 2013 Dec;42:41-8
references.pmid: 23892002
references.citation: Pediatr Nephrol. 1998 Apr;12(3):218-21
references.pmid: 9630041
references.citation: Arterioscler Thromb Vasc Biol. 2012 Nov;32(11):2794-802
references.pmid: 22936341
references.citation: Int Arch Occup Environ Health. 1987;59(1):21-30
references.pmid: 3793241
references.citation: J Environ Health. 2005 Oct;68(3):10-7, 32
references.pmid: 16312251
references.citation: N Engl J Med. 1980 May 15;302(20):1128-31
references.pmid: 7366636
references.citation: Arch Toxicol. 2006 Aug;80(8):473-80
references.pmid: 16502312