This study reveals that there is a positive correlation between blood mercury levels and oral tissue response in mother rats, however, the negative impact of mercury on oral tissues of offspring rats was due to high mercury levels in their mothers' blood during pregnancy. Further clinical studies are recommended to test our findings in man.  

Biomonitoring studies show that humans carry a body burden of multiple classes of contaminants which are not often studied together. Many of these chemicals may be hepatotoxic. We used the 2003–2004 National Health and Nutrition Examination Survey to evaluate the relationship between alanine aminotransferase (ALT) a sensitive indicator of liver cell injury, and 37 environmental contaminants, comprising heavy metals, non dioxin-like polychlorinated biphenyls (PCBs), and dioxin-like compounds.

In 1997 The Environmental Protection Agency compiled the Mercury Study Report to Congress. This document covers the human health effects of mercury and mercury compounds. Upon reading the symptoms of mercury vapor-induced neurotoxicity and the toxicokinetics, it is apparent that mercury has great potential to mimmic symptoms of dementia and Alzheimer's disease.

This paper, written by Mats Hanson, examines studies from leading research institutes around the world. His research reveals that there has been a documented trend in positive health changes after removal of amalgam fillings since as far back as 1986 (at least!)

This article explorers the statistics concerning long term nicotine gum chewing and determines if chewing nicotine gum can elevate the levels of mercury released into the body from amalgam fillings.

The concept of accumulative micro-mercurial neurotoxicity with specific reference to dental amalgam, has been well documented and prolonged exposure to mercury has been associated with the unique lesions of the AD brain. Therefore, amalgam, as the largest source of mercury vapor in the general population, should be included in the differential diagnosis of patients being investigated for neuro-psychiatric problems and shortterm memory loss.

In the present study we describe a strong, positive correlation between mercury exposure from dental amalgam fillings and urinary mercury excretion over a 7-year longitudinal course of amalgam treatment in children. These findings are relevant within the context of children’s health risk assessment and suggest directions for future research to determine whether differential sensitivities to mercury between boys and girls do exist.

Silver amalgam specimens treated with 10% carbamide peroxide bleaching agents produced a statistically significant increase in the quantity of Hg released after 15 days compared with the control group. Additional studies are needed to assess the impact of this increase. However, the authors recommend avoiding the indiscriminate exposure of silver amalgam restorations to carbamide peroxide bleaching agents.

Stephen M. Koral, DMD, FIAOMT writes an un-biased article that looks into commonly accepted variables concerning exposure, toxicology and risk assessment in the use of amalgam fillings in dentistry and the effect it will have on the use of amalgam in the future.

Inhalation experiments in rats and primates show deposition of Hg in spinal cord following single high-dose short-time exposure. Mercury accumulation in anterior horn cells is followed by axonal atrophy and distal weakness similar to the clinical picture in human ALS. Respiratory Hg exposure could contribute to elevated concentrations of Hg found in cerebrospinal fluid from patients with ALS.

The data from this study revealed that amalgam sensitive individuals are quite heterogeneous with respect to treatment effects and that there may be a true association between symptoms and mercury levels in subgroups. Therefore, the question of 'amalgam sensitivity' should concentrate more on individual vulnerability, either in the form of biological (e.g. genetic) or psychosocial (e.g. personality, experiences, health beliefs and concerns) predispositions.

All the articles analyzed here showed that mercury  exposure is ototoxic, inducing peripheral and/or central hearing loss. It is a consensus in the literature that acute and long-term exposure produces irreversible damage to the central auditory system. Measuring mercury levels with biomarkers was unable to predict the relationship between the degree of mercury poisoning and the degree of damage to the auditory system.

In a group of individuals with health complaints attributed to amalgam fillings the complaints were reduced after removal of the fillings. To which level the complaints were reduced varied for the different symptoms and the inter-ndividual variation of intensities of complaints was considerable. Several factors may be of importance for the observed reduction of complaint intensity.

The present studies demonstrate significant adverse effects on neurobehavioral functions associated with chronic Hg exposure and the CPOX4 genetic variant among children, with effects manifested predominantly among boys. These findings are the first to describe a genetic polymorphism that modifies the effects of Hg exposure on neurobehavioral functions in children, and suggest directions for future research to define mechanisms underlying differential sensitivity to mercury between boys and girls.

In 2008 California's Office of Environmental Health Hazard Assessment concluded a new risk assessment of mercury and adjusted its chronic mercury reference exposure levels down to 0.03 μg Hg/m3. This level is ten times lower than the outdated and flawed, 20 year old chronic mercury reference exposure levels of 0.3 μg Hg/m3 as set by the Environmental Protection Agency.

This study investigated the effect of elemental mercury exposure on renal function and antioxidative enzymes activity as a possible mechanism of renal affection among dental staff. Compared to the control group, urinary and blood mercury were significantly higher in the exposed group. Glutathione peroxidase and superoxide dismutase activities in blood were significantly decreased and were negatively correlated with duration of work.

Exposure to mercury vapour or inorganic mercury compounds can impair fertility in laboratory animals. To study the effects of mercury vapour on fertility in women, eligibility questionnaires were sent to 7000 registered dental assistants. Detailed information was collected on mercury handling practices and the number of menstrual cycles without contraception it had taken them to become pregnant.

The Agency for Toxic Substances and Disease Registry (ATSDR) toxicological profile succinctly characterizes the toxicologic and adverse health effects information for the hazardous substance described here. Each peer-reviewed profile identifies and reviews the key literature that describes a hazardous substance's toxicologic properties.

The aim of this study was to generate hypotheses concerning associations between background exposures and pregnancy. One µg/L increases in blood Hg are associated with decreases of 35% (P=0.03) and 33% (P=0.01) in clinical and biochemical pregnancies, respectively. These data suggest that low-level, background exposures to Hg and Cd may interfere with pregnancy following IVF.

We examined the effect of mercury (Hg) associated with dental amalgam fillings on biomarkers of renal and oxidative stress in children between the ages of 5–15.5 years. Our data provide evidence that low exposure to Hg from dental amalgam fillings exerts an effect on kidney tubular functions in children. Oxidative stress may have played a role in this mechanism. The results of this study would also suggest that urinary NAG is the most sensitive of all the investigated renal biomarkers.