We get mercury in our bodies from many different sources including mercury vapors in ambient air, ingesting it via drinking water, fish, dental amalgams, vaccines, occupational exposures, home exposures including fluorescent light bulbs, thermostats, batteries, red tattoo dye, skin-lightening creams, over-the-counter products such as contact lens fluid and neosynephrine, and more.
You absorb about 80 percent of inhaled mercury vapor and nearly 100 percent of the mercury in fish through your gut. Once this mercury is in your body it is then primarily distributed in the kidneys and brain and can be readily transferred to the fetus via the placenta.
The only way it can get out of your body is via urine, feces, expired air, and breast milk. The major reason it is toxic to human biology is because mercury has the ability to bind to sulfur-containing molecules in the body (found in nearly every enzyme and in the mitochondria), as well as other chemical binding sites in the cells.
We’ve learned a lot about how this mercury effects us and our children from reported exposures to mercury over the last 100 years. These include epidemics such as the Minimata Bay exposures in Japan, acrodynia or pink disease in children from calomel (HgCl) used in teething powder, “mad hatter syndrome” or erethism, and methylmercury fungicide grain seed exposures in Iraq and Pakistan.
The symptoms and diseases these exposures have caused are varied and mimic many other conditions. Nervous system toxicity can cause erethism (“mad hatter syndrome” as mentioned above) with symptoms of shyness; laughing, crying, and dramatic mood swings for no apparent reason; nervousness, insomnia, memory problems, and the inability to concentrate.
Other neurologic symptoms may include encephalopathy (non-specific brain malfunction), nerve damage, Parkinsonian symptoms, tremor, ataxia (loss of balance), impaired hearing, tunnel vision, dysarthria (slurred speech), headache, fatigue, impaired sexual function, and depression.
Kidney toxicity leads to proteinura (protein in the urine) and acute renal failure. Gastrointestinal symptoms include nausea, vomiting, diarrhea, and colitis. Skin toxicity causes allergic dermatitis, chelitis (cracked corners of the mouth), gingivitis (gum disease), stomatitis (sores in the mucous membranes of the mouth) and excessive salivation.
Now, there are different types of mercury. Nearly all human exposures to one type, methylmercury, come from fish. Severe symptoms start with exposure to doses of 100 mcg/kg/day, mild symptoms with more than 10 mcg/kg/day, and sub-clinical symptoms with less than 1 mcg/kg/day. These symptoms include late development in walking and talking in children and decreased performance on neurological tests.
Methylmercury (also called organic mercury) is found predominately in red blood cells, which is what doctors check when they do a blood test for mercury. But unless you’ve been eating fish with mercury recently, you won’t see your total body level of mercury.
Plus, mercury is lipophilic, meaning that it concentrates in fatty tissues, especially in the brain, which is made mostly of fat. That means that blood levels aren’t an accurate measurement of total body burden of mercury.
Inorganic mercury from dental fillings (amalgams) is found in plasma but is rapidly cleared and stored in your tissues. Inorganic mercury is also converted from methylmercury by the body and is the main form of mercury in brain, which can lead to dementia, autism, ADHD and more.
Some of us are very good at detoxifying mercury and other toxins, while some of us store toxins like a toxic waste dump. Genetic variations (called polymorphisms) make some people more prone to metal toxicity. One gene in particular is very important because it’s related to the body’s production of glutathione, our most powerful detoxifier and antioxidant. Your body can only excrete mercury when it’s bound with glutathione.
The polymorphism of the gene that controls the enzyme glutathione-S-transferase (GSST) prevents excretion of mercury. That is the gene problem I have that led to my mercury toxicity. When that happens, the mercury stays in tissues and does damage. Plus, mercury also binds to key enzymes that help us produce glutathione — in effect helping itself accumulate in our bodies.
Research also shows that people suffering from symptoms like fatigue, irritability, mood disorders, poor concentration, headaches, and insomnia due to their amalgam fillings are more likely than their peers to have the apolipoprotein E 4 (ApoE 4) gene.
ApoE 4 is known as the “Alzheimer’s gene.” It also promotes heart disease. ApoE 4 reduces detoxifying activity. This means that people with this gene can’t get rid of mercury from their brains, contributing to its toxic effects on this organ.
10 Truths and Tips about Mercury Toxicity
- Industrial exposure to mercury is significant and mostly comes from coal burning (220 million pounds a year) and chlor-alkali plants.
- The main ways that humans are exposed to mercury are from contaminated fish and dental amalgams or silver fillings.
- Mercury can affect nearly all your organs, especially the brain, heart, kidneys, and gut.
- Many chronic diseases may be caused or worsened by mercury, including neurological diseases, ADHD, autism, heart disease, autoimmune diseases, and more.
- Some of us are genetically better adapted to detoxify mercury than others, leading to variable effects within the population.
- You should reduce your exposure by avoiding large ocean fish (like tuna, swordfish, shark, and tilefish) and river fish. Eat only small wild fish. If it fits in your pan, it is probably okay.
- Blood tests are relatively worthless for analyzing mercury toxicity, unless you have had a significant recent exposure or eat a lot of sushi or tuna.
- Hair tests only check for mercury from fish, not from fillings so they only give you a partial picture.
- The only way to find out your total body load of mercury is to take a medication with sulfur molecules that binds to the mercury like fly paper. This is called DMSA or DMPS. This test should ONLY be done by a trained physician and involves taking one dose of this medicine, followed by a 6- or 24-hour urine collection to see how much comes out.
- If you are toxic and sick, you may consider addressing your dental health by seeing a biological dentist who can safely help you deal with mercury in your mouth.