title: Blood lead concentrations and children's behavioral and emotional problems: a cohort study.
abstract: OBJECTIVE
  The association between lead exposure and children's IQ has been well studied, but few studies have examined the effects of blood lead concentrations on children's behavior.
  
  
  OBJECTIVE
  To evaluate the association between blood lead concentrations and behavioral problems in a community sample of Chinese preschool children with a mean blood lead concentration of less than 10 µg/dL.
  
  
  METHODS
  A prospective cohort study was conducted at 4 preschools in Jintan, Jiangsu province of China. Participants included 1341 children aged 3 to 5 years.
  
  
  METHODS
  Lead.
  
  
  METHODS
  Blood lead concentrations were measured in children aged 3 to 5 years. Behavioral problems were assessed using Chinese versions of the Child Behavior Checklist and Caregiver-Teacher Report Form when children were aged 6 years.
  
  
  RESULTS
  The mean (SD) blood lead concentration was 6.4 (2.6) µg/dL, with the 75th and 90th percentiles being 7.5 and 9.4 µg/dL, respectively. General linear modeling showed significant associations between blood lead concentrations and increased scores for teacher-reported behavioral problems. A 1-µg/dL increase in the blood lead concentration resulted in a 0.322 (95% CI, 0.058 to 0.587), 0.253 (95% CI, 0.016 to 0.500), and 0.303 (95% CI, 0.046 to 0.560) increase of teacher-reported behavior scores on emotional reactivity, anxiety problems, and pervasive developmental problems, respectively (P < .05), with adjustment for parental and child variables. Spline modeling showed that mean teacher-reported behavior scores increased with blood lead concentrations, particularly for older girls.
  
  
  CONCLUSIONS
  Blood lead concentrations, even at a mean concentration of 6.4 µg/dL, were associated with increased risk of behavioral problems in Chinese preschool children, including internalizing and pervasive developmental problems. This association showed different patterns depending on age and sex. As such, continued monitoring of blood lead concentrations, as well as clinical assessments of mental behavior during regular pediatric visits, may be warranted.
authors.affiliation: School of Nursing, University of Pennsylvania, Philadelphia2School of Medicine, University of Pennsylvania, Philadelphia.
authors.forename: Jianghong
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Medicine, Indiana University, Indianapolis4School of Public Health, Shandong University, Jinan, China.
authors.forename: Xianchen
authors.initials: X
authors.lastname: Liu
authors.affiliation: Center for Outcomes Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Nell Hodgson School of Nursing, Emory University, Atlanta, Georgia.
authors.forename: Linda
authors.initials: L
authors.lastname: McCauley
authors.affiliation: School of Nursing, University of Pennsylvania, Philadelphia2School of Medicine, University of Pennsylvania, Philadelphia.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Pinto-Martin
authors.affiliation: School of Nursing, University of Pennsylvania, Philadelphia.
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Nursing, University of Pennsylvania, Philadelphia.
authors.forename: Linda
authors.initials: L
authors.lastname: Li
authors.affiliation: Xinhua Hospital, MOE-Shanghai Key Laboratory of Children's Environmental Health, Shanghai Jiaotong University School of Medicine, China.
authors.forename: Chonghuai
authors.initials: C
authors.lastname: Yan
authors.affiliation: National Institute of Environmental Health Sciences, National Institutes of Health, Bethesda, Maryland.
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Rogan
mesh_terms: D002653:Child Behavior Disorders / Q000139:chemically induced* / Q000453:epidemiology; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D007854:Lead / Q000097:blood*; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D013054:Spectrophotometry, Atomic; D011795:Surveys and Questionnaires
chemical_list: D007854:Lead
references.citation: Neurotoxicol Teratol. 2001 Nov-Dec;23(6):511-8
references.pmid: 11792521
references.citation: Paediatr Child Health. 2010 Jan;15(1):17-22
references.pmid: 21197164
references.citation: Biol Trace Elem Res. 2011 Aug;142(2):148-58
references.pmid: 20625937
references.citation: J Clin Child Adolesc Psychol. 2011;40(3):456-67
references.pmid: 21534056
references.citation: Lancet. 2011 Apr 30;377(9776):1474-6
references.pmid: 21492927
references.citation: Pediatrics. 1998 Mar;101(3):E10
references.pmid: 9481029
references.citation: Environ Res. 2000 May;83(1):1-22
references.pmid: 10845777
references.citation: Biol Psychiatry. 2008 Feb 1;63(3):325-31
references.pmid: 17868654
references.citation: Pers Individ Dif. 2011 Aug 1;50(8):1222-1226
references.pmid: 21686316
references.citation: PLoS One. 2013 May 29;8(5):e65230
references.pmid: 23734241
references.citation: J Clin Child Adolesc Psychol. 2003 Sep;32(3):328-40
references.pmid: 12881022
references.citation: Arch Environ Health. 2000 Sep-Oct;55(5):330-5
references.pmid: 11063408
references.citation: Environ Res. 2006 Jul;101(3):412-8
references.pmid: 16442092
references.citation: Neurotoxicology. 2006 Sep;27(5):693-701
references.pmid: 16889836
references.citation: Am J Epidemiol. 1999 Apr 15;149(8):740-9
references.pmid: 10206624
references.citation: Environ Sci Pollut Res Int. 2012 Sep;19(8):3268-75
references.pmid: 22374191
references.citation: Int J Epidemiol. 2010 Jun;39(3):668-74
references.pmid: 19433517
references.citation: Environ Health Perspect. 2009 Oct;117(10):1607-11
references.pmid: 20019913
references.citation: J Am Acad Child Adolesc Psychiatry. 1999 Jun;38(6):708-15
references.pmid: 10361789
references.citation: Environ Health Perspect. 2009 Aug;117(8):1309-12
references.pmid: 19672413
references.citation: Acta Histochem. 2012 Jan;114(1):41-5
references.pmid: 21392819
references.citation: N Engl J Med. 1992 Oct 29;327(18):1279-84
references.pmid: 1383818
references.citation: Neurotoxicol Teratol. 2004 May-Jun;26(3):359-71
references.pmid: 15113598
references.citation: J Child Psychol Psychiatry. 2010 Sep;51(9):1050-7
references.pmid: 20406335
references.citation: Arch Environ Health. 1991 Nov-Dec;46(6):351-60
references.pmid: 1772260
references.citation: Int J Nurs Stud. 2011 Jul;48(7):904-13
references.pmid: 21601204
references.citation: Toxicology. 2013 Sep 6;311(1-2):3-12
references.pmid: 23632092
references.citation: J Emot Behav Disord. 2012;20(2):68-81
references.pmid: 29416292
references.citation: Clin Child Fam Psychol Rev. 2000 Mar;3(1):37-60
references.pmid: 11228766
references.citation: J Consult Clin Psychol. 2000 Dec;68(6):1038-50
references.pmid: 11142538
references.citation: Drug Chem Toxicol. 2005;28(1):67-77
references.pmid: 15720036
references.citation: Toxicol Lett. 2012 Apr 5;210(1):15-23
references.pmid: 22285975
references.citation: Hum Mov Sci. 2004 Oct;23(3-4):475-88
references.pmid: 15541530
references.citation: Occup Environ Med. 1998 Aug;55(8):573-6
references.pmid: 9849547
references.citation: Bioinorg Chem Appl. 2003;:333-42
references.pmid: 18365064
references.citation: J Am Acad Child Adolesc Psychiatry. 2000 Nov;39(11):1371-8
references.pmid: 11068892
references.citation: Int J Occup Environ Health. 2005 Apr-Jun;11(2):138-43
references.pmid: 15875889
references.citation: Epidemiology. 1995 Jul;6(4):356-65
references.pmid: 7548341
references.citation: Environ Health Perspect. 2002 Jul;110(7):721-8
references.pmid: 12117650
references.citation: Environ Health Perspect. 2006 Dec;114(12):1904-9
references.pmid: 17185283
references.citation: JAMA. 1996 Feb 7;275(5):363-9
references.pmid: 8569015
references.citation: Sci Total Environ. 2009 Jun 15;407(13):3986-93
references.pmid: 19395068
references.citation: J Clin Child Adolesc Psychol. 2010;39(2):234-41
references.pmid: 20390814
references.citation: J Abnorm Child Psychol. 2011 Feb;39(2):251-64
references.pmid: 20821258
references.citation: Pediatrics. 2007 Mar;119(3):e650-8
references.pmid: 17332184
references.citation: Med Sci Monit. 2006 Oct;12(10):BR325-9
references.pmid: 17006395
references.citation: Am J Public Health. 1998 Mar;88(3):481-6
references.pmid: 9518990
references.citation: Neurotoxicology. 2010 Jun;31(3):259-66
references.pmid: 20226811
references.citation: Neurotoxicology. 2011 Aug;32(4):458-64
references.pmid: 21477618
references.citation: Environ Res. 1994 Jul;66(1):12-30
references.pmid: 8013435
references.citation: Environ Health Perspect. 2007 Jul;115(7):1113-7
references.pmid: 17637931
references.citation: Brain Res. 2000 Sep 8;876(1-2):201-4
references.pmid: 10973610
references.citation: Paediatr Perinat Epidemiol. 2012 Jan;26(1):61-9
references.pmid: 22150709
references.citation: Environ Health Perspect. 2008 Oct;116(10):1401-6
references.pmid: 18941585
references.citation: Neurotoxicol Teratol. 2010 Mar-Apr;32(2):273-9
references.pmid: 20005947
references.citation: Environ Health Perspect. 2005 Jul;113(7):894-9
references.pmid: 16002379
references.citation: Intelligence. 2012 Mar-Apr;40(2):139-144
references.pmid: 29416189
references.citation: PLoS Med. 2008 May 27;5(5):e101
references.pmid: 18507497
references.citation: Neurotoxicology. 2012 Aug;33(4):644-51
references.pmid: 22664101