Mercury in dental fillings a risk to the kids

J Expo Sci Environ Epidemiol. 2007 Sep 12 [Epub ahead of print]Links
Maternal amalgam dental fillings as the source of mercury exposure in
developing fetus and newborn.Palkovicova L, Ursinyova M, Masanova V,
Yu Z, Hertz-Picciotto I.
aDepartment of Environmental Medicine, Slovak Medical University,
Bratislava, Slovakia.

Dental amalgam is a mercury-based filling containing approximately 50%
of metallic mercury (Hg(0)). Human placenta does not represent a real
barrier to the transport of Hg(0); hence, fetal exposure occurs as a
result of maternal exposure to Hg, with possible subsequent
neurodevelopmental disabilities in infants. This study represents a
substudy of the international NIH-funded project "Early Childhood
Development and polychlorinated biphenyls Exposure in Slovakia". The
main aim of this analysis was to assess the relationship between
maternal dental amalgam fillings and exposure of the developing fetus
to Hg. The study subjects were mother-child pairs (N=99).
Questionnaires were administered after delivery, and chemical analyses
of Hg were performed in the samples of maternal and cord blood using
atomic absorption spectrometry with amalgamation technique. The median
values of Hg concentrations were 0.63 mug/l (range 0.14-2.9 mug/l) and
0.80 mug/l (range 0.15-2.54 mug/l) for maternal and cord blood,
respectively. None of the cord blood Hg concentrations reached the
level considered to be hazardous for neurodevelopmental effects in
children exposed to Hg in utero (EPA reference dose for Hg of 5.8 mug/
l in cord blood). A strong positive correlation between maternal and
cord blood Hg levels was found (rho=0.79; P0.001). Levels of Hg in
the cord blood were significantly associated with the number of
maternal amalgam fillings (rho=0.46, P0.001) and with the number of
years since the last filling (rho=-0.37, P0.001); these associations
remained significant after adjustment for maternal age and education.
Dental amalgam fillings in girls and women of reproductive age should
be used with caution, to avoid increased prenatal Hg exposure.Journal
of Exposure Science and Environmental Epidemiology advance online
publication, 12 September 2007; doi:10.1038/sj.jes.7500606.

PMID: 17851449 [PubMed - as supplied by publisher]

Thanks Vince