Hair Mineral Test - Research
Implications of Lead Toxicity
Lead is a heavy metal commonly found in our environment today. According to the National Academy of Sciences, approximately 600,000 tons of lead is added to the atmosphere each year. Since lead is known to be cumulative, contributing to a variety of neurological disorders and ailments, it is recognized as the most dangerous of the toxic metals, and a major threat to the biological systems of both humans and animals.
Effects of lead on the biological system
Organs affected by lead toxicity are the kidneys, liver and pancreas. The brain, nervous system, bone marrow, immune system and collagen syntheses are also adversely affected by excess lead concentrations. Lead will also decrease some ATPases and enzymes necessary for normal cellular oxidation.
Lead expresses its toxicity by several mechanisms. It avidly inhibits amino levulinic acid dehydratase (ALAD), one of the enzymes that catalyse the synthesis of heme from porphyrin. Inhibition of ALAD causes accumulation of protoporphyrin in erythrocytes, which is significant marker for lead exposure. Anemia due to lack of heme is frequently observed in lead toxicity. Lead is also an electrophile that avidly forms covalent bonds with the sulfhydryl group of cysteine in proteins. Thus, proteins in all tissues exposed to lead will have lead bound to them. Keratin in hair contains a high fraction of cysteine relative to other amino acids and avidly binds lead; hair tissue mineral analysis for lead is a good marker for exposure
Symptoms associated with excessive lead burden
|Long term memory deficits
Dietert et al. at Cornell University. Institute for Comparative and Environmental Toxicology in Ithaca added small amounts of lead to the drinking water of pregnant rats. They set levels equivalent to those consumed by humans with lead paint or lead pipes in their houses. The immune systems of their birth, the offspring showed an abnormal immune response. Their Type I immune system, which mounts attacks on tumours and viruses with white blood cells, was severely depressed compared to controls. The young rats also showed an unusually overactive Type II immune function, which is associated with fighting parasitic infection. Immunologists believe that abnormally strong Type II responses like this could lie behind diseases such asthma.
Dietert concluded that pregnant women who are exposed to lead even for a short time might unwittingly risk the health of their babies. It is possible even very low levels might have profound effects during development when the immune system is vulnerable.
Chlopicka et al. reported significant findings in Biological Trace Element Research, from hair tissue mineral analysis of 158 children aged 8-15 (98 boys and 60 girls). The children population under investigation was divided according to their sex. The study revealed that both the hair and blood of the boys accumulated more lead and cadmium than those of the girls. A correlation between the concentrations of these metals was confirmed.
Normally, 1 to 10 percent of the ingested lead is absorbed into the body, and approximately 30 to 50 percent of inhaled sources, depending upon the form. Studies have shown that a much higher rate of absorption occurs in children. Children can absorb as much as 50 percent of the amount ingested, which may account for the rise in learning disabilities and behavioral disturbances in children of the United States.
Nutrients in relation to lead
Not everyone absorbs the same amount of lead even with equal exposure. A predisposition may be accounted for by the following:
Other nutrient such as minerals magnesium, copper, chromium, vitamin C and the B vitamins have been shown to protect against the effects of lead as will, either by decreasing its absorption and tissue deposition, or by reducing or blocking the effects of lead upon enzyme systems.
Testing for lead contamination
Almost all of the lead circulating in the blood is found within the erythrocytes. A clinical characteristic of lead toxicity or plumbism is, basophilic stippling of red blood cells. The upper limit for whole blood levels of lead is 30 micrograms per deciliter. This level is controversial at present, as levels well below these limits have been known to alter the central nervous system function within children.
If the kidneys are being affected by excess lead accumulation, aminoaciduria, phosphaturia and glucose urea may be found. Reduced plasma levels of 1,25-dihydroxycholecalciderol may also be found.
Since lead interferes with heme synthesis enzymes, elevated urinary excretion of protoporphyrin may be elevated in the red cells.
Hair Tissue Mineral Analysis (HTMA)
Since lead normally departs from the blood for deposition into such tissues as the bone, teeth, and hair, hair mineral testing can be an accurate screening tool for toxic metal accumulation. It is also economical, and an easily obtainable tissue.
Hair has been used as one of the tissues of choice by the Environmental Protection Agency (E.P.A.) in determining toxic metal exposure. A 1980 report released by the E.P.A stated that human hair can be effectively used for biological monitoring of toxic metals. This report confirmed the findings of other studies which concluded that hair may be a more appropriate tissue for studying community exposure to toxic metals than blood or urine analysis. Investigators in Japan, Sweden, Canada, and the United States have shown that the concentrations of elements in the hair provide an accurate and permanent record of exposure.
Removal of lead from the body
Ethylenediaminetetracetic (EDTA) is frequently used for more severe cases of lead poisoning. Penicillamine and British anti-lewisite (BAL) are also considered therapeutic agents for acute toxicity.
Evidence now shows that even low lead levels can adversely affect neurological function. Since poor diet has been related to higher lead accumulation, it is possible that therapeutic nutritional application can relieve low lead toxicity and the disorders that accompany.
Alginate and pectin have been noted to decrease the absorption of ingested lead. Calcium, magnesium, zinc, copper, and iron not only help protect from the absorption of lead, but can hasten its removal when properly used.
Ideal lead nutrient ratios
Our laboratories have established the upper "acceptable" limit for tissue lead at 0.5 milligrams percent (mg%) or 5 parts per million (PPM). Since evidence of lead toxicity exists well below the levels recognised as significant, the lead level in relation to other mineral levels should be considered more important for diagnosis, rather than the tissue lead level alone. If any of the following ratios are below normal, it can be assumed that lead may be interfering with that mineral participation in enzyme functions.
Tissue Mineral Analysis
|Ideal Nutrient Levels
|Ideal Minimum Lead Ratios
|Ca/Pb.....84 to 1
|Mg/Pb.....12 to 1
|Cu/Pb.....5 to 1
|Zn/Pb.....40 to 1
|Fe/Pb.....5.6 to 1
Supplementation of individual minerals would be indicated if lower than normal ratios are present. Appropriate vitamins should also be used in conjunction with dietary changes that would further help decrease the body burden of lead.
Removal of any form of indigestible lead is imperative if any nutrient mineral ratio is lower than ideal. Avoid any canned foods sealed with solder, or acidic foods stored in earthenware containers. Check to see if lead water pipes are being used. If lead water pipes are used, either filter the water, or change to bottled water. Avoid foods grown near highways and jogging near heavily traveled roads. Opening the windows throughout the home at least once per week would be suggested in order to decrease concentrations of lead accumulating inside well-insulated buildings.
Toxic lead is recognised as the most hazardous of all the toxic metals. Children, the elderly, and pregnant women are the most susceptible to the effects of lead, i.e. absorption and retention. Since even low levels of lead can affect the fetus and contribute to learning disorders, behavioral disorders, emotional and physical health problems, routine screening of patients presenting these symptoms may uncover low level lead toxicity.
Lead Poisoning Masquerading as Chronic Fatigue Syndrome
A 47-year-old woman was admitted to hospital with confusion and headache. She had a 10-year history of debility, weight loss, constipation and difficulty with abstract reasoning, diagnosed as chronic fatigue syndrome. She had a normocytic anaemia, with anisocytosis, target cells, and prominent basophilic stippling. Blood lead level was then measured due to this finding, which was at 11.7 mol/L.
This patient had been labeled as having chronic fatigue syndrome for over 10 years before she was found to have lead poisoning, which explained all her symptoms.
Mesch U et al. The Lancet 347:1996
Sources of Lead
* Lead Based hair Colourings: Lead based colourings such as Restoria, Grecian Formular, Amway, Youth Hair, and RD for Men will contribute significantly to hair lead elevation. Urinary studies have shown that continued or chronic exposure to lead based cosmetics and dyes will result in lead absorption into the body via hair and skin.
It is estimated that the daily amount of lead received from food and air sources today can total 50 to 900 micrograms per day. This is almost 1 milligram per day for individuals living in areas with high lead concentrations.