Mercury

“The Dental Products Panel met on December 14 and 15, 2010, to discuss and make recommendations on scientific issues raised in petitions received by FDA concerning the final rule on the classification of dental amalgam, which published in the Federal Register on August 4, 2009 (74 FR 38686). The Panel deliberated on the exposure to mercury from dental amalgam, reference exposure levels, human clinical studies and the strength and weaknesses of the available evidence.”

“Autism spectrum disorders (ASDs) also known as pervasive developmental disorders (PDD) are a behaviorally defined group of neurodevelopmental disorders that are usually diagnosed in early childhood. ASDs disproportionately affect male children. Mercury (Hg) a heavy metal, is widespread and persistent in the environment. Mercury is a ubiquitous source of danger in fish, drugs, fungicides/herbicides, dental fillings, thermometers, and many other products. Elevated Hg concentrations may remain in the brain from several years to decades following exposure. This is important because investigators have long recognized that Hg is a neurodevelopmental poison; it can cause problems in neuronal cell migration and division, and can ultimately cause cell degeneration and death. Case-reports of patients have described developmental regressions with ASD symptoms following fetal and/or early childhood Hg exposure, and epidemiological studies have linked exposure to Hg with an elevated risk of a patient being diagnosed with an ASD. Immune, sensory, neurological, motor, and behavioral dysfunctions similar to traits defining or associated with ASDs were reported following Hg intoxication with similarities extending to neuroanatomy, neurotransmitters, and biochemistry. The sexual dimorphism of ASDs may result from synergistic neurotoxicity caused by the interaction of testosterone and Hg; in contrast, estrogen is protective, mitigating the toxicity of Hg. Mercury exposure may significantly increase androgen levels, and as a result, patients diagnosed with an ASD may significantly benefit from anti-androgen therapy. Finally, the clinical geneticist has a wealth of biomarkers to evaluate and treat patients diagnosed with an ASD.”

“Despite the fact that humans are exposed to multiple forms of mercury (elemental, inorganic, and organic), most research on mercury toxicity has focused on methylmercury (MeHg) and on neurotoxic outcomes and mechanisms. Recent work has indicated that the immunotoxic effects of mercury compounds may be significant contributors to human disease as well as mechanistically relevant to other target organ toxicities. In this study, we compared the effects of inorganic Hg (iHg) to organic Hg species (MeHg and ethylmercury, EtHg) in human peripheral blood mononuclear cells (PBMCs) in vitro at sub-cytotoxic concentrations, using methods developed to characterize response of human PBMCs to iHg in vitro. PBMCs were isolated from six volunteer blood donors (three males and three females) and cultured in the presence and absence of lipopolysaccharide (LPS) and low levels (up to 200nM of each Hg species, separately) for 24h in culture. Cell culture supernatants were analyzed for cytokine concentrations with a bead-based multiplex assay. We report that iHg and MeHg both increase pro-inflammatory cytokine release in LPS-stimulated PBMCs, while EtHg decreases IFN-gamma release as well pro-inflammatory cytokine release. IL-17 release is significantly increased only in response to iHg treatment. Levels of anti-inflammatory cytokines (IL-1Ra and IL-10) were not significantly altered by any Hg treatment. These results indicate that both organic and inorganic species of Hg can affect the human immune system, but that they may exert different effects on immune function.”

“It is well known that certain forms of organic mer-cury (such as methylmercury) are neurotoxic. What has been of signi?cant interest in recent years relates to the levels of mercury which become bioavailable after injecting vaccines which contain the ethylmercury-based preservative Thimerosal and whether those levels are signi?cant enough to disrupt normal neuronal communication. This study does not attempt to extrapolate the observed effects of Thimerosal on neurons of the pond snail to the effects of Thimerosal on the normal neuronal development of the infant human. What we show is that there is a clear disruption of the baseline neuronal communication pattern when the extracted central nervous system is exposed to Thimerosal at 100 µM. We note that this concentration far exceeds that which is bioavailable in normal Thimerosal-preserved vaccines.”

“DR. JEFFCOAT: Good morning. I would like to call this meeting to order. And thank you all for coming out on a very cold day. I’m Dr. Marjorie Jeffcoat and I’m officially calling this meeting of the Dental Products Panel to order. I’m Dr. Marjorie Jeffcoat, Chairperson of the Panel. I’m a professor at the University of Pennsylvania and the former dean. I have expertise in clinical studies, especially related to systemic diseases and oral health. At this meeting, the Panel will discuss and makerecommendations on scientific issues raised in the petitions received by the
FDA concerning the final rule on the classification of dental amalgam, which was published in the Federal Register on August 4th, 2009. Issues raised in the petitions include the adequacy of the risk assessment performed by the FDA in classifying dental amalgam, in light of a new report on risk assessment issued by the National Academy of Sciences entitled ‘Science and Decisions: Advancing Risk Assessment.’ And that was in the National Academy Press in 2009.”

“Universal hepatitis B vaccination was recommended for U.S. newborns in 1991; however, safety findings are mixed. The association between hepatitis B vaccination of male neonates and parental report of autism diagnosis was determined. This cross-sectional study used weighted probability samples obtained from National Health Interview Survey 1997-2002 data sets. Vaccination status was determined from the vaccination record. Logistic regression was used to estimate the odds for autism diagnosis associated with neonatal hepatitis B vaccination among boys age 3-17 years, born before 1999, adjusted for race, maternal education, and two-parent household. Boys vaccinated as neonates had threefold greater odds for autism diagnosis compared to boys never vaccinated or vaccinated after the first month of life. Non-Hispanic white boys were 64% less likely to have autism diagnosis relative to nonwhite boys. Findings suggest that U.S. male neonates vaccinated with the hepatitis B vaccine prior to 1999 (from vaccination record) had a threefold higher risk for parental report of autism diagnosis compared to boys not vaccinated as neonates during that same time period. Nonwhite boys bore a greater risk.”

“DR. JEFFCOAT: I would like to call this second day of the meeting of the Dental Products Panel to order. I’m Dr. Marjorie Jeffcoat, chairperson of the Panel. I’m a professor at the University of Pennsylvania, and my — and I am a periodontist and my expertise is in clinical studies. At this meeting the Panel will discuss and make recommendations on specific scientific issues raised in petitions received by the FDA concerning the final rule of the classification of dental amalgam, which was published in the Federal Register on August 4, 2009. Issues raised in the petitions include the adequacy of the risk assessment performed by the FDA in classifying dental amalgams in light of the new report on risk assessments issued by the National Academy of Sciences entitled ‘Science and Decisions Advancing Risk Assessment,’ and that is in the National Academy Press 2009.”

N/A

“For the week following amalgam removal, body mercury levels increase significantly, depending on protective measures taken, but within 2 weeks levels fall significantly (82, 89). Chronic conditions can worsen temporarily, but usually improve if adequate precautions are taken to reduce exposure during removal.”

“Background Systemic allergic contact dermatitis has been reported in patients with adverse health effects linked to dental alloy restorations. Here we report a case of severe systemic allergic contact dermatitis caused by allergy to metals released by galvanic corrosion between mercury dental amalgam and a titanium dental implant. Methods A 36-year-old woman reporting severe systemic dermatitis with intractable pruritus was examined in April 2002. The rapid onset of dermatitis began several months after she received 2 titanium screws which were implanted in her maxilla and jaw. Examination showed extensive dermatitis with erythema, dry skin with scaling and crusting on face, neck, and inguinal area (Fig.1). She had 2 titanium endosseous implants (on 1.6 and 3.6 area) and 1 mercury amalgam filling on the mandibular left first molar (3.7). We suspected an high rate of intraoral metal ions release due to galvanic corrosion between mercury amalgam filling on 3.7 and the titanium implant-supported gold-alloy crown in 3.6 area. Amalgam tattoo was present on 1.6 gingival area. Results She was patch-tested with general and dental series. We observed very strong positive allergic reactions to nickel sulfate 5% (+++) and potassium dichromate 0.5% (+++), gold sodium thiosulfate 0.5% (++), all in petrolatum. Lymphocyte stimulation test confirmed nickel allergy (stimulation index: 6.7). Dental amalgam as well as metal ceramic crown on implant were removed to eliminate the oral galvanism corrosion. The systemic contact dermatitis resolved completely within 8 months after the removal of mercury amalgam. There have been reports of skin disorders associated with mercury amalgam such as nummular dermatitis, eczema, urticaria, pink exanthem, cutaneous lichen planus, orofacial granulomatosis. Adverse events associated with titanium implants are yellow nail syndrome, sinusitis, neuropathy, implant-related immune activation, arthritis, and leukopenia. Conclusions Clinicians should consider allergy to metal ions released from galvanic couple between mercury amalgam and titanium implant in patients with systemic dermatitis.”