Tag Archives: Fetus Study

Mercury (Thimerosal) Study: Maternal transfer of mercury to the developing embryo/fetus: is there a safe level?

“Toxicological & Environmental Chemistry  Read Abstract…
Maternal transfer of mercury to the developing embryo/fetus: is there a safe level?

Ian A. Browna* & David W. Austinb
Received: 27 Jun 2012
Accepted: 21 Aug 2012
Accepted author version posted online: 28 Aug 2012
Version of record first published: 20 Sep 2012


Mercury (Hg) exposure is ubiquitous in modern society via vaccines, fish/crustacea, dental amalgam, food, water, and the atmosphere. This article examines Hg exposure in the context of primary exposure to pregnant women and secondary exposure experienced by their unborn babies. Babies in utero are particularly at risk of higher Hg exposure than adults (on a dose/weight basis through maternal Hg transfer via the placenta), and are more susceptible to adverse effects from mercury and its biologically active compounds. It is, therefore, critical that regulatory advisories around maximum safe Hg exposures account for pregnant women and secondary exposure that children in utero experience. This study focused on standardized embryonic and fetal Hg exposures via primary exposure to the pregnant mother of two common Hg sources (dietary fish and parenteral vaccines). Data demonstrated that Hg exposures, particularly during the first trimester of pregnancy, at well-established dose/weight ratios produced severe damage to humans including death. In light of research suggestive of a mercuric risk factor for childhood conditions such as tic disorders, cerebral palsy, and autism, it is essential that Hg advisories account for secondary prenatal human exposures.