title: Boron exposure through drinking water during pregnancy and birth size.
abstract: Boron is a metalloid found at highly varying concentrations in soil and water. Experimental data indicate that boron is a developmental toxicant, but the few human toxicity data available concern mostly male reproduction.
  
  
  
  To evaluate potential effects of boron exposure through drinking water on pregnancy outcomes.
  
  
  
  In a mother-child cohort in northern Argentina (n=194), 1-3 samples of serum, whole blood and urine were collected per woman during pregnancy and analyzed for boron and other elements to which exposure occurred, using inductively coupled plasma mass spectrometry. Infant weight, length and head circumference were measured at birth.
  
  
  
  Drinking water boron ranged 377-10,929μg/L. The serum boron concentrations during pregnancy ranged 0.73-605μg/L (median 133μg/L) and correlated strongly with whole-blood and urinary boron, and, to a lesser extent, with water boron. In multivariable-adjusted linear spline regression analysis (non-linear association), we found that serum boron concentrations above 80μg/L were inversely associated with birth length (B-0.69cm, 95% CI -1.4; -0.024, p=0.043, per 100μg/L increase in serum boron). The impact of boron appeared stronger when we restricted the exposure to the third trimester, when the serum boron concentrations were the highest (0.73-447μg/L). An increase in serum boron of 100μg/L in the third trimester corresponded to 0.9cm shorter and 120g lighter newborns (p=0.001 and 0.021, respectively).
  
  
  
  Considering that elevated boron concentrations in drinking water are common in many areas of the world, although more screening is warranted, our novel findings warrant additional research on early-life exposure in other populations.
authors: Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
authors: Annachiara Malin
authors: AM
authors: Igra
authors: Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden. Electronic address: florencia.harari@ki.se.
authors: Florencia
authors: F
authors: Harari
authors: Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
authors: Ying
authors: Y
authors: Lu
authors: Atención Primaria de la Salud, Área Operativa XXIX, Hospital Dr. Nicolás Cayetano Pagano, San Antonio de los Cobres, 4411, Salta, Argentina.
authors: Esperanza
authors: E
authors: Casimiro
authors: Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden.
authors: Marie
authors: M
authors: Vahter
mesh_terms: D000293:Adolescent; D000328:Adult; D001118:Argentina; D001724:Birth Weight; D001895:Boron / Q000097:blood / Q000633:toxicity*; D015331:Cohort Studies; D060766:Drinking Water / Q000737:chemistry*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy / Q000097:blood*; D011256:Pregnancy Outcome; D055815:Young Adult
chemical_list: D060766:Drinking Water; D001895:Boron
keywords: Birth size; Birth weight; Boron; Drinking water; Lithium; Prenatal exposure