title: A comparison of urinary mercury between children with autism spectrum disorders and control children.
abstract: BACKGROUND
  Urinary mercury concentrations are used in research exploring mercury exposure. Some theorists have proposed that autism is caused by mercury toxicity. We set out to test whether mercury concentrations in the urine of children with autism were significantly increased or decreased compared to controls or siblings.
  
  
  METHODS
  Blinded cohort analyses were carried out on the urine of 56 children with autism spectrum disorders (ASD) compared to their siblings (n = 42) and a control sample of children without ASD in mainstream (n = 121) and special schools (n = 34).
  
  
  RESULTS
  There were no statistically significant differences in creatinine levels, in uncorrected urinary mercury levels or in levels of mercury corrected for creatinine, whether or not the analysis is controlled for age, gender and amalgam fillings.
  
  
  CONCLUSIONS
  This study lends no support for the hypothesis of differences in urinary mercury excretion in children with autism compared to other groups. Some of the results, however, do suggest further research in the area may be warranted to replicate this in a larger group and with clear measurement of potential confounding factors.
authors.affiliation: North Yorkshire and York Primary Care Trust, York, United Kingdom. Barry.wright@nyypct.nhs.uk
authors.forename: Barry
authors.initials: B
authors.lastname: Wright
authors.forename: Helen
authors.initials: H
authors.lastname: Pearce
authors.forename: Victoria
authors.initials: V
authors.lastname: Allgar
authors.forename: Jeremy
authors.initials: J
authors.lastname: Miles
authors.forename: Clare
authors.initials: C
authors.lastname: Whitton
authors.forename: Irene
authors.initials: I
authors.lastname: Leon
authors.forename: Jenny
authors.initials: J
authors.lastname: Jardine
authors.forename: Nicola
authors.initials: N
authors.lastname: McCaffrey
authors.forename: Rob
authors.initials: R
authors.lastname: Smith
authors.forename: Ian
authors.initials: I
authors.lastname: Holbrook
authors.forename: John
authors.initials: J
authors.lastname: Lewis
authors.forename: David
authors.initials: D
authors.lastname: Goodall
authors.forename: Ben
authors.initials: B
authors.lastname: Alderson-Day
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis* / Q000652:urine*; D015331:Cohort Studies; D003404:Creatinine / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008628:Mercury / Q000652:urine*; D011379:Prognosis
chemical_list: D003404:Creatinine; D008628:Mercury