Sensible steps for purging lead and other toxic metals can have profound health implications for people of all ages.
by John Pittman, MD, and Mark N. Mead, MSc
Lead is a toxic metal with an ancient relationship to public health. The Greek physician Hippocrates, considered the “father of Western Medicine”, is thought to have written the first case report of lead poisoning in 600 BC. In ancient Rome, lead’s extensive use in cooking utensils, cosmetics, wine vessels, aqueducts and water pipes may have contributed to widespread toxic effects—possibly even accounting for imperial madness, infertility, and miscarriage rates that kept the ruling class from replacing themselves. The bones from Roman graves show high concentrations of lead. It seems ironic that the powerful empire may have been defeated more primarily by its lack of environmental health awareness than by any opposing army per se.
Our recent history has again boosted the lead count, but by very different means. Three industrial centuries have greatly increased the mining and smelting of lead, resulting in its widespread dispersal in air, water, and soil. In the 1970s, when leaded gasoline was in vogue, automobiles were the number one contributor to lead pollution here in the United States. Thankfully, this form of gasoline was phased out, and blood lead levels dropped as a consequence. Other preventive strategies such as eliminating lead as an additive from paint and as a component of lead solder in food cans have resulted in further lowering of blood lead levels among U.S. children. (Note: Lead from solder leaches more readily into acidic foods, like tomatoes and citrus, than into nonacid and dry foods. Tests of canned tomato products in the late 1980s found that about one quarter of the cans tested contained lead-soldered seams.)
Despite these important public health measures, lead continues to be a problem today. Modern body burdens of lead are still hundreds of times higher than those natural, prehistoric levels with which we evolved. The metal is used in construction, for decorations, in pottery glazes, and even as a food additive. Lead soldering in old water supply pipes results in some lead leaching into drinking water supplies. Imported toys and other children’s products may be a major source of lead exposure for U.S. children. In 2007, tests on more than 1,200 children’s products found that 35 percent contain lead—many with levels far above the federal recall standard used for lead paint, according to the Michigan-based Ecology Center along with the national Center for Health, Environment and Justice and groups in eight other states.
Much of the concern about lead’s harmful effects has focused on younger people. An estimated 310,000 U.S. children younger than five years have elevated blood lead levels, according to a 2009 estimate by the Centers for Disease Control and Prevention. Unfortunately, younger brains are uniquely susceptible to the toxic effects of lead. By the same token, however, many children with elevated blood lead levels show huge improvements in their health and behavior when we take the proper steps to “get the lead out.”
A Threat to Adults as Well
It’s not just young people who are at risk of lead-related health effects. We now know that lead promotes hypertension and boosts the risk of dying from cardiovascular disease. For example, in the October 2006 issue of Environmental Health Perspectives, researchers reported on a 12-year study of nearly 9,800 adults, all over age 40, who were part of the Third National Health and Nutrition Examination Survey, or NHANES III. Those people with blood lead levels higher than 10 µg/dL were 59% more likely to die from cardiovascular disorders compared with people who had blood lead below 5 µg/dL.
Another NHANES III-based study looked into the connection between blood lead levels and overall mortality over a 12-year period. Reporting in the medical journal Circulation on September 26, 2006, the researchers concluded that blood lead levels as low as 2 µg/dL—a level deemed safe by the U.S. Centers for Disease Control—were linked with a significantly increased risk of overall mortality and an increased risk of dying from both coronary heart disease and stroke. Given that nearly 40% of U.S. adults have a 2 µg/dL blood lead level, the public health implications of these findings are immense. Yet another study from NHANES found that people with higher blood lead levels were nearly three times more likely to have chronic kidney disease, and twice as likely to have peripheral arterial disease, as reported in the 10 October 2005 Archives of Internal Medicine.
These research findings prompt the question: How many people seeking mainstream medical treatment for these conditions never get their lead levels checked and therefore end up taking costly medications for the rest of their lives? How many people are going in for costly cardiac drugs and surgery without realizing that metal toxicity may be a critical underlying cause or promoting factor? Imagine how health care could be improved by addressing this common yet widely unrecognized biological insult.
Long-term effects of lead on the brain have also been identified. A recent look at data from the Nurses Health Study found a significant link between cognitive deficits in the elderly and higher lead levels in the tibia or “shinbone” (a leg bone that records long-term lead exposure). Several studies have now shown that memory loss and other kinds of psychological deterioration are associated with the tibia lead levels in older people. In the January 2009 issue of Neuropsychology, experts reported that bone lead levels predicted cognitive decline in people over age 55. Also, hypertension could play a mediating role in the relationship between lead exposure and age-related cognitive decline, as reported online in the 27 May 2009 issue of Neurotoxicology.
It’s important to remember that the development of senile dementia is most likely preceded by small and often subtle decreases in cognitive functioning over time. In this regard, adults are at risk of “silent” toxicity from low-level lead exposures that gradually damage the brain over decades. Thus, the brain-toxic effects of lead may be very hard to perceive or sort out in the context of the aging process.
How Low Can You Go?
Overt symptoms of lead toxicity are rare at blood lead levels of less than 70 µg/dL. But much lower levels are still toxic to the brain, and as we just noted above, lead can alter brain function in a gradual, silent manner, whereby the cognitive and behavioral changes are themselves so gradual as to be almost imperceptible. For very young people, however, the effects of lead exposure are more readily seen in the form of reduced test scores, spelling ability, reading comprehension, and attention span—all outcomes that have been significantly correlated with blood lead levels.
The U.S. Centers for Disease Control has set a safe blood lead level for children at 10 µg/dL. Any lead level above 10 µg/dL may promote hyperactivity, distractibility, memory loss, hearing loss, and low IQ scores. But new research indicates that even lower lead levels—on the order of 3 to 5 µg/dL—may compromise one’s cognitive ability. For infants and young children, there currently appears to be no safe threshold for lead exposure, especially if other brain-toxic pollutants (e.g., mercury and all pesticides on the market) and poor dietary habits are thrown into the mix.
Just how bad is the problem of lead exposure in the general population? A study in the March 2, 2009 issue of Pediatrics concludes that, although blood lead levels have dropped since the 1970s, they continue to be higher for low-income children, non-Hispanic black children, and children living in older housing (built before 1950). Some of the children with high blood lead levels have been exposed to lead from consumer products, imported toys, imported traditional medicines, and house wares. And children whose parents work with lead are confronted with “take-home” lead exposure.
The authors of the above-mentioned Pediatrics report recommended more aggressive efforts to identify sources of lead, and to measure blood lead levels in those children most at risk. In this regard, North Carolina was among the first states to institute such proactive strategies. In the 1980s, public health officials suspected a link between high lead levels and the state’s low national ranking in SAT scores. All NC property owners were required by law to begin eliminating lead hazards such as peeling paint or contaminated soil in places where younger children (under age 6) spend time. The state’s Childhood Lead Poisoning Prevention Act, which went into effect on July 1, 1990, was designed to detect and correct high-lead situations prior to exposing the children.
Nutritional Keys and the Calcium Connection
Lead’s health effects also bear a close relationship to calcium. Like various radioactive elements, most of the lead we absorb is eventually stored in our bones, where over 99% of the body’s calcium is also stored. Scientists once thought the bone’s lead deposits were relatively harmless; however, when calcium leaves the bones, lead is released simultaneously, and this results in a rise in the blood lead level.
Whenever the blood’s calcium level is low, calcium is drawn from the bones to function in more essential body processes like nerve transmission and heartbeat. Such losses are most dramatic when people consume diets high in meats and other protein-rich foods, and high-fat foods and caffeine can further exacerbate the losses. For woman, bone-calcium losses occur naturally during pregnancy, lactation, and menopause—a process further amplified by the dietary habits just mentioned.
People who minimize these dietary habits and consume plenty of dark leafy greens—which are rich in calcium—will be less likely to experience the lead-calcium time bomb. Taking a high-quality calcium supplement is also recommended, ideally one that contains either calcium citrate or hydroxyapatite.
A substantial amount of today’s lead exposure happens through the food chain—from airborne lead that falls on agricultural areas. Such fallout has resulted in major increases in the lead content of rice, oats, lettuce, cabbage, and other vegetable foods. Once lead enters the food chain, it becomes increasingly concentrated in animal flesh, which is yet another reason to avoid a heavy meat diet. EPA officials estimate that U.S. adults consume, on average, about 30 to 40 micrograms of lead each day through food, the major route for adult exposure.
Successful Removal of Toxic Metals
Since lead has an obvious potential to promote hypertension, hamper learning ability, and disrupt other aspects of behavior and personality, it behooves us to find ways to pull the lead out of our bodies. At this time, chelation therapy is the only established way to do eliminate toxic metals. The word chelation derives from the Greek word “chele”, which refers to the claw of a crab or lobster. The “claw” in chelation therapy is the chelator itself, a substance that binds to toxic metals, essentially pulling them out of the body through the urine and feces.
Among the oldest of these “claws” is the synthetic amino acid disodium ethylenediamine tetra-acetic acid (EDTA). When given intravenously, EDTA binds ionic calcium, trace elements and other divalent cations and transports these bound components out of the body in the urine. The standard approach to EDTA chelation is to mix the compound with antioxidant nutrients in an intravenous solution that is administered repeatedly over weeks to months. Between chelation sessions, high oral doses of antioxidant vitamins and mineral supplements are typically recommended.
Chelation therapy with EDTA and/or DMSA has long been used for the treatment of lead poisoning. The U.S. Food and Drug Administration has approved both drugs as a treatment for lead and heavy metal poisoning. Some physicians only recommend chelation therapy when the blood lead level reaches 45 μg per dL (2.17 μmol per L) or greater, as reported in the 15 March 2010 American Family Physician. However, this high blood level usually only reflects an acute lead exposure. Repeated or chronic low-level exposures are more common and result in accumulations of lead in the bones. Thus, it is possible to have a much lower blood level, on the order of 10 μg per dL or lower, yet still have a high body burden of lead.
To assess your child’s overall body burden—and to get some sense of how much of the metal might be stored in the bones—the urinary chelation challenge test should be used in addition to the blood test. The challenge test involves giving EDTA and then measuring how much lead comes out in the urine. If findings from the challenge test indicate a high body burden, then the chelation approach can be very beneficial. (Note: Another method entails the use of Kappa x-ray fluorescence, which measures lead in bone, usually in the tibia and patella.)
If your child’s lead count is unacceptably high, oral or intravenous EDTA, along with natural chelating agents, can be used to draw the lead out of the tissues and blood before sending it on to the kidneys and being excreted in the urine. When properly administered, such chelation sessions may help safeguard your child’s intellectual potential. For example, kids with either ADHD or Autism Spectrum Disorders who have high lead levels often show substantial improvements in their overall behavior when the lead levels are brought down.
Similarly, adults with high lead levels will generally experience a gradual improvement in symptoms after a series of chelation treatments and an extended period whereby their blood lead level remains low. Those with very high lead levels will show greater improvements after chelation, including better cognitive function. But in most cases, the improvements will lag behind the decline in blood lead levels, probably because of the relatively slower removal of lead from the brain and central nervous system. The pace of improvement can be highly variable from one individual to the next, ranging from weeks to a year or more depending on the magnitude of the lead burden as well as the individual’s overall nutritional status.
Many people only show the neuro-cognitive benefits when chelation therapy is used in the context of comprehensive nutritional support and other forms of treatment, such as cognitive rehabilitation and occupational therapy. It’s important to note that short-term improvements in cognitive functioning following a decline in the blood lead level may not be able to override or reverse the harmful effects of long-term cumulative lead exposures.
This is why getting the lead out at an earlier stage of life is so critical, and why preventing or minimizing lead exposures is always the top priority. There is a critical time period—less than 3 years of age—during which lead and other toxic metals can have a profound long-range impact on IQ, attention span, and antisocial behaviors. Chelation therapy’s ability to impact neurobehavioral development is clearly greatest in these early years. But older children, too, can benefit from appropriate removal of lead and other metals. In many cases, we find that children with ADHD, learning disabilities, or Autism Spectrum Disorders will not respond well to other biological therapies or to behavioral approaches until their toxic metal burden has been substantially reduced.
An Integrative Approach is Essential
Chelation is clearly the best treatment against metal poisoning, but it must be performed correctly in order to be effective. Research reviewed in the October 2008 issue of the Indian Journal of Medical Research indicates that chelation therapy is most effective when combined with specific antioxidants and nutritional factors that support the body as it attempts to eliminate the toxic metals. Along these same lines, research reported in the 15 April 2007 issue of Cellular & Molecular Biology confirms the value of chelation therapy for reversing a situation of toxic overload with lead and arsenic. The authors of this paper, titled “Arsenic and lead-induced free radical generation and their reversibility following chelation”, emphasized the importance of judicious chelation therapy in combination with specific antioxidant nutrients and herbals to support optimal detoxification.
Our own clinical experience at the Raleigh-based Carolina Center for Integrative Medicine suggests, similarly, that chelation is most effective when accompanied by supportive strategies such as selenium, zeolites, herbal chelators, and glutathione-boosting nutritional strategies. The lack of inclusion of these supportive measures in randomized clinical trials may explain why the few trials completed to date have not demonstrated any major benefits. You can have the most rigorous clinical study design on the planet, but if your intervention is bogus, so too will be the results of the study.
If lead-laced wine did indeed cause the madness of Caesars and bring the Roman Empire to ruin, then the rising tide of toxic metal pollution means that our society’s sanity and intelligence may be at stake. Unless we clean up our act and fast, we may be putting our brains at risk for the indefinite future. Using chelation therapy within the framework of integrative medicine—that is, coupled with individually tailored nutritional and herbal support—is our best hope for turning the biological tide in a body already burdered with lead, mercury, cadmium, and other toxic metals.
To reach the authors or schedule a consultation, or to obtain more information on how to optimize the removal of toxic metals, contact the Carolina Center for Integrative Medicine in Raleigh, NC at 919-571-4391, or visit the website at www.carolinacenter.com.