Maternal-fetal distribution of mercury ( sup 203 Hg) released from dental amalgam fillings
- Univ. of Calgary, Alberta (Canada)
In humans, the continuous release of Hg vapor from dental amalgam tooth restorations is markedly increased for prolonged periods after chewing. The present study establishes a time-course distribution for amalgam Hg in body tissues of adult and fetal sheep. Under general anesthesia, five pregnant ewes had twelve occlusal amalgam fillings containing radioactive 203Hg placed in teeth at 112 days gestation. Blood, amniotic fluid, feces, and urine specimens were collected at 1- to 3-day intervals for 16 days. From days 16-140 after amalgam placement (16-41 days for fetal lambs), tissue specimens were analyzed for radioactivity, and total Hg concentrations were calculated. Results demonstrate that Hg from dental amalgam will appear in maternal and fetal blood and amniotic fluid within 2 days after placement of amalgam tooth restorations. Excretion of some of this Hg will also commence within 2 days. All tissues examined displayed Hg accumulation. Highest concentrations of Hg from amalgam in the adult occurred in kidney and liver, whereas in the fetus the highest amalgam Hg concentrations appeared in liver and pituitary gland. The placenta progressively concentrated Hg as gestation advanced to term, and milk concentration of amalgam Hg postpartum provides a potential source of Hg exposure to the newborn. It is concluded that accumulation of amalgam Hg progresses in maternal and fetal tissues to a steady state with advancing gestation and is maintained. Dental amalgam usage as a tooth restorative material in pregnant women and children should be reconsidered.
- OSTI ID:
- 6771449
- Journal Information:
- American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 258; ISSN 0002-9513; ISSN AJPHA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BODY FLUIDS
CARIES
DAYS LIVING RADIOISOTOPES
DENTISTRY
DIGESTIVE SYSTEM
DISTRIBUTION
DOMESTIC ANIMALS
ELEMENTS
EVEN-ODD NUCLEI
FETUSES
HEAVY NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MATERIALS
MEDICINE
MERCURY
MERCURY 203
MERCURY ISOTOPES
METABOLISM
METALS
NUCLEI
ORAL CAVITY
PATHOLOGICAL CHANGES
PREGNANCY
RADIOISOTOPES
RUMINANTS
SHEEP
TEETH
TISSUE DISTRIBUTION
TRACER TECHNIQUES
VERTEBRATES