Sources of Toxic Heavy Metal Exposure
By Pamela Levin, R.N.
Note: This is the second in a series of articles on toxic heavy metals.
Indecent Exposure. Toxic heavy metals cause all manner of strange symptoms due to the fact that they accumulate in body tissues over time. Yet modern people are constantly exposed to more and more of these noxious substances, making it a matter of survival to become aware of and eliminate as many sources of exposure as possible. The following are some of these metals and their common sources of contamination.
Mercury leads the list of toxic metals because it is more toxic than lead, cadmium or arsenic. A chief source of mercury exposure is from dental fillings. Labeled “silver” amalgam, they are actually over 50% mercury. Scientific studies have repeatedly demonstrated that these fillings produce mercury vapor when they are chewed on or when hot food is consumed. This vapor is then absorbed into the body. When mercury accumulates in the cells, it produces neurotoxicity and kidney damage.
Another source of mercury, and one that has received a lot of press recently, is seafood. Fish become contaminated from water that carries mercury all the way from mines in the middle of the country, polluting the water table, lakes and streams, and eventually the ocean. Thus mercury-polluted water is an additional source of exposure. A 6-ounce can of tuna fish now contains an average of 17 micrograms of mercury. Some 60,000
children are born each year with developmental impairments triggered by fetal exposure to methyl mercury, usually as a result of their moms having eaten tainted fish
A third source has been vaccinations. Mercury has been, and in some cases, continues to be used as a vaccine preservative in the form of thimerosal, a compound that contains 49.6 % mercury by weight. For example, a pediatric dose of hepatitis B vaccine contains slightly more mercury than the 17 micrograms found in a can of tuna fish. The FDA's Center for Biologics Evaluation & Research (CBER) added the total amount of mercury given to children through vaccines in the
immunization schedule, which included 3 doses of DTP, 3 of Hib (hemophilus influenza type B, a bacterial disease) and 3 of hepatitis B vaccine. These add up to 187.5 micrograms of mercury for a 6 month old infant, which exceeds the safe limits established by the EPA (Environmental Protection Agency) for six month olds. Many parents and some health professionals believe the mercury in these vaccinations caused autism in their children, giving rise to a number of lawsuits. Currently it is believed that mercury is no longer used in vaccines in the
, supposedly because it is unnecessary in single dose vaccines (multiple dose vaccines containing mercury are now exported to other countries). However some evidence exists that mercury is present even in single dose vaccines. Mercury content of currently used vaccines can be found at http://www.vaccinesafety.edu/thi-table.htm
Other sources of mercury exposure include latex wall paint, mercury vapor lamps, sewage sludge and skin lightening creams.
Aluminum exposure results from aluminum cookware and any food prepared in aluminum cookware, antacids, antiperspirants, astringents, aluminum cans (especially soft drinks, where the acid in the drink leaches the toxic metal), kitchen utensils, paints, dental composites, baby powder, toothpaste, some teas, human breast milk, infant formulas (whether from soy or dairy), aluminum foil, baking powder, adult and children’s aspirin, many prescription drugs, food additives such as sodium aluminum phosphate (in processed cheese), potassium alum (which is used to whiten flour), table salt (which contains silicoaluminate and/or aluminum calcium silicate to make it pour freely). It is also found in appliances, building materials, paints and fireworks; and in the production of glass, rubber, and ceramics.
Antimony exposure results mostly from in medicines and pigments. It is also a common air pollutant. Workers in starter battery production are exposed as part of their work, where its inhalation results in inflammation of the lungs, chronic bronchitis, and chronic emphysema. According to the Centers for Disease Control, it is especially concentrated in the air near industries that process or release it, particularly smelters, coal-fired plants, and refuse incinerators. It is used in the manufacture of pottery, glass, bullets, fireworks, plastics, petroleum products and fabricated metals products.
Arsenic exposure comes from poisons, pigments, dyes, wood preservatives, wine, well water, coal burning, seafood (namely shellfish) and treated lumber, as inorganic arsenic compounds are used to preserve wood. They are also used to make insecticides and weed killers. Labels of treated wood and insecticides say whether or not they contain arsenic. Inorganic arsenic is also found in cigarettes and fireworks. The January issue of Environmental Health Perspectives reports that the levels of arsenic l in young chickens, or "broilers," may be three to four times greater than in other poultry and meat.
Lead is introduced into our bodies from car exhaust, canned food, hair dyes, newsprint and tap water. Some dolomite supplements taken to support bone health also contain lead. The lead interferes with progesterone production, causing spontaneous abortions and preventing stimulation of osteoblasts, the bone-building cells. Lead exposure also results from lead pipes and lead-lined tanks in domestic water supplies. Other sources include contaminated water, canning, pottery glaze, polluted air, cigarette smoke, cosmetics, and paints containing lead. The total lead intake from food and beverages for adults in various industrialized countries has been estimated to by 250-300 ug/day.
Cadmium enters our bodies in water from galvanized pipes, evaporated milk, shellfish, sewage sludge, paint, pigments and air pollution. It is also a primary contaminant of cigarette smoke, whether inhaled directly or through second-hand smoke. It is estimated each cigarette adds 1mcg. of cadmium to the inhaler’s body. Other sources include refined foods, coffee, tea, coal burning, fungicides sprayed on foods and tobacco, softened water, some well water. Organ meats can also be sources of exposure because the animals’ bodies are contaminated and cadmium is stored in their organs.
Chromium exposure received a gigantic public relations boost in the film Erin Brockovich. In its chromium III form, it is an essential nutrient, while in its chromium IV (hexavalent) form it is a toxic substance. Main sources of exposure to the toxic forms include dyes, pigments, air pollution and dental crowns. Environmental exposure occurs from airborne emissions from chemical plants and incineration facilities, effluents from chemical plants, contaminated landfill, cement dust, road dust from catalytic converter erosion and asbestos brake lining erosion, tobacco smoke, topsoil and rocks.
Occupational exposure occurs during welding of alloys or steel, leather tanning (soluble Cr [III]), chrome electroplating (soluble Cr [VI]), chrome alloy production, textile manufacturing, paints/pigments, (insoluble Cr[VI]), photoengraving, copier servicing, antifreeze, antialgae agents, production of high-fidelity magnetic audio tapes, tattooing, wood preservatives, agricultural antifungicides, porcelain and ceramics manufacturing and glassmaking.
Given that we undergo so many sources of exposure, and that the negative health effects accumulate over time, it is small wonder that Majid Ali, M.D., a specialist in the diagnosis and treatment of heavy metal toxicity, recommends that all people undergo heavy metal detoxification as a matter of routine starting at the age of 20 and regularly thereafter.
How can you know if heavy metal toxicity is an issue for you? That topic, the assessment of toxic metal load, is the subject of the next article in this series. Methods for detoxification will be covered last.
Copyright 2004 by Pamela Levin, R.N. All rights reserved.
Pamela Levin, R.N. is a local health practitioner specializing in clinical nutrition. She wrote “Perfect Bones, A Six Point Plan to Promote Healthy Bones” to detail the process she used for herself and her clients to rebalance the body and regain bone health. Published by Celestial Arts, it is at amazon.com, www.perfectbones.com. She can be reached at (707) 462 2217.