title: Availability of arsenic in human milk in women and its correlation with arsenic in urine of breastfed children living in arsenic contaminated areas in Bangladesh.
abstract: BACKGROUND
  Early life exposure to inorganic arsenic may be related to adverse health effects in later life. However, there are few data on postnatal arsenic exposure via human milk. In this study, we aimed to determine arsenic levels in human milk and the correlation between arsenic in human milk and arsenic in mothers and infants urine.
  
  
  METHODS
  Between March 2011 and March 2012, this prospective study identified a total of 120 new mother-baby pairs from Kashiani (subdistrict), Bangladesh. Of these, 30 mothers were randomly selected for human milk samples at 1, 6 and 9 months post-natally; the same mother baby pairs were selected for urine sampling at 1 and 6 months. Twelve urine samples from these 30 mother baby pairs were randomly selected for arsenic speciation.
  
  
  RESULTS
  Arsenic concentration in human milk was low and non-normally distributed. The median arsenic concentration in human milk at all three time points remained at 0.5 μg/L. In the mixed model estimates, arsenic concentration in human milk was non-significantly reduced by -0.035 μg/L (95% CI: -0.09 to 0.02) between 1 and 6 months and between 6 and 9 months. With the progression of time, arsenic concentration in infant's urine increased non-significantly by 0.13 μg/L (95% CI: -1.27 to 1.53). Arsenic in human milk at 1 and 6 months was not correlated with arsenic in the infant's urine at the same time points (r = -0.13 at 1 month and r = -0.09 at 6 month). Arsenite (AsIII), arsenate (AsV), monomethyl arsonic acid (MMA), dimethyl arsinic acid (DMA) and arsenobetaine (AsB) were the constituents of total urinary arsenic; DMA was the predominant arsenic metabolite in infant urine.
  
  
  CONCLUSIONS
  We observed a low arsenic concentration in human milk. The concentration was lower than the World Health Organization's maximum permissible limit (WHO Permissible Limit 15 μg/kg-bw/week). Our findings support the safety of breastfeeding even in arsenic contaminated areas.
authors.forename: Md Rafiqul
authors.initials: MR
authors.lastname: Islam
authors.forename: John
authors.initials: J
authors.lastname: Attia
authors.forename: Mohammad
authors.initials: M
authors.lastname: Alauddin
authors.forename: Mark
authors.initials: M
authors.lastname: McEvoy
authors.forename: Patrick
authors.initials: P
authors.lastname: McElduff
authors.forename: Christine
authors.initials: C
authors.lastname: Slater
authors.forename: Md Monirul
authors.initials: MM
authors.lastname: Islam
authors.forename: Ayesha
authors.initials: A
authors.lastname: Akhter
authors.forename: Catherine
authors.initials: C
authors.lastname: d'Este
authors.forename: Roseanne
authors.initials: R
authors.lastname: Peel
authors.forename: Shahnaz
authors.initials: S
authors.lastname: Akter
authors.forename: Wayne
authors.initials: W
authors.lastname: Smith
authors.forename: Stephen
authors.initials: S
authors.lastname: Begg
authors.affiliation: Centre for Clinical Epidemiology & Biostatistics (CCEB), The School of Medicine and Public Health, Faculty of Health, The University of Newcastle, Lot 1 Kookaburra Circuit, New Lambton Heights, NSW 2305, Australia. Milton.Hasnat@newcastle.edu.au.
authors.forename: Abul Hasnat
authors.initials: AH
authors.lastname: Milton
mesh_terms: D000293:Adolescent; D000328:Adult; D001151:Arsenic / Q000032:analysis* / Q000652:urine*; D001459:Bangladesh; D001942:Breast Feeding; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis* / Q000652:urine*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D055815:Young Adult
chemical_list: D004785:Environmental Pollutants; D001151:Arsenic