by Mark Edwards

Summary: The blue-green algae Spirulina may serve as a safe and low cost chelator to remove the lead that currently poisons the brains of Flint Michigan children.

The best way to lower an elevated blood lead level is to prevent continued exposure to lead. Flint children are now receiving bottled and other sources of clean water, which stops the bioaccumulation of lead in their bodies. However, many children are left with dangerously high levels of lead in the brains and bodies. Left untreated, the lead will create catastrophic damage to their vital organs. The children need a solution that gets the lead out.


They need a chelator that vigorously bioabsorbs lead. Biosorption is the process whereby treatment by a biological material removes chemical molecules. Considerable research over the past 20 years has shown that the cyanobacteria Spirulina biomass works effectively for heavy metal removal from aqueous solutions. Water scientists have known for decades that Spirulina operates as a strong biosorbent for the removal of the heavy metals chromium (Cr(VI)), lead (Pb(II)) and other heavy metals from the aqueous samples.

Additional research extended the effectiveness of Spirulina as biosorbent material for lead. When tested against other biosorption materials, the Spirulina adsorption process was found to be faster and more complete. Maximum heavy metal removal could be achieved within one hour of contact time. The observed values of lead adsorbed were significantly higher than values reported for other adsorbents in the literature. Other algae species that are also strong biosorbents include brown marine algae such as Ascophyllum and Sargassum.

Once lead bioaccumulates in the brain, the blood-brain barrier tends to lock it there.

blood-brain-barrierThe blood-brain barrier protects the neural tissue from variations in blood composition and toxins. Elsewhere in the body the extracellular concentrations of hormones, amino acids and potassium undergo frequent fluctuations, especially after meals, exercise or stressful times. The blood-brain barrier keeps the brain relatively stable but makes lead chelation difficult.

The blood-brain barrier
EDTA chelation does not penetrate cells and cannot penetrate the blood-brain barrier.

Spirulina’s nano cell size offers a substantial advantage over other chelation substances for heavy metals in the brain. The Spirulina nano cells easily penetrate the blood brain barrier, chelate with available lead and then pass harmlessly out of the brain in the blood. The chelated lead from the brain, vital organs and other body tissues becomes excreted in the urine stream.

Biosorbent mechanism

Spirulina’s biosorbent mechanism is fascinating. Spirulina works so effectively as a biosorbent because the nano-sized individual cells create a massive surface area. The cylindrical shaped cells, observable in the pictures below, string together with a trichome width from only 6 to 12 μm, (microns). The helix diameter varies from 30 to 70 μm, which also adds substantial surface area.

Spirulina’s nano cells create massive surface area

Spirulina’s nano cells create massive surface area

Most of the heavy metals such as lead are first adsorbed, (adhere) to the Spirulina’s outer surface. Spirulina’s enormous surface area facilitates substantial lead adsorption. Smaller amounts are then absorbed into the organism. Of course, Spirulina used as a biosorbent for heavy metals is not edible but may be diluted and used as a fertilizer.

Several companies have business models where they use various algae species to remove heavy metals from wastewater or mine tailings. They then recover the metals with chemicals and sell the valuable metals to industrial customers.

The blue-green algae Spirulina may offer an inexpensive, easy to administer nanochelator solution that imposes negligible side effects. Spirulina is a type of blue-green algae that is rich in protein, vitamins, minerals, carotenoids, and antioxidants that can help protect cells from damage. It contains nutrients, including B complex vitamins, beta-carotene, vitamin E, manganese, zinc, copper, iron, selenium, and gamma linolenic acid (an essential fatty acid).

Safe nanochelator

A 2006 report using human subjects shows Spirulina worked as an effective heavy metals chelator solution. Bangladesh has the worst arsenic pollution in the world, putting millions of children at risk. Forty-one chronic arsenic poisoning patients were randomly treated orally by placebo (17 patients) or Spirulina extract (250 mg) plus zinc (2 mg) (24 patients) twice daily for 16 weeks. Each patient was supplied with arsenic-safe drinking water by installing a locally made water filter at the household level. Effectiveness of Spirulina extract plus zinc was evaluated by comparing changes in skin manifestations, (clinical scores), arsenic contents in urine and hair, between the placebo-and Spirulina extract and zinc-treated groups.

High arsenic intake resulted in increased excretion of arsenic in the urine. There was a sharp increase in urinary excretion of arsenic at four weeks following Spirulina plus zinc administration and the effect was continued for another two weeks.

Spirulina extract plus zinc removed 47% of the arsenic from scalp hair. Spirulina extract had no noticeable side effects that required a physician’s attention. The clinical scores for melanosis before and after treatment with placebo was not statistically significant (p > 0.05). In Spirulina extract plus zinc-treated group, clinical scores were statistically significant (p < 0.01). Results showed that Spirulina plus zinc offers a natural treatment of chronic arsenic poisoning.

Spirulina has a long history of human consumption and is known as a safe, nutritious microalgae according to the National Institute of Health. In the past 30 years, it has been marketed and consumed as a safe human food and has been approved as a food for human consumption by many governments, health agencies and associations of over 20 countries. The University of Maryland Medical Center agrees with many other sources that report that Spirulina appears safe, even at high doses.

Forrest and Haaken enjoy fresh spirulina and lemonade popsicles on a hot summer afternoon Source: Robert Henrikson, CEO,

Forrest and Haaken enjoy fresh spirulina and lemonade popsicles on a hot summer afternoon Source: Robert Henrikson, CEO,

The superb site,, managed by Robert Henrikson provides an extensive bibliography on the science behind Spirulina for both health and nutrition. The National Institute of Health references the and warns that it is important to buy a reputable brand of Spirulina because it can be contaminated with other substances.

Animal studies

Several studies have demonstrated Spirulina acts as an effective chelator for lead in animals. Experimental animals with lead poisoning were fed on a standard laboratory diet with or without Spirulina 5% for several weeks. The results showed that Spirulina prevented the expected lead acetate-induced changes on plasma and liver lipid levels. Spirulina succeeded to improve the biochemical parameters of the liver and kidney towards the normal values of the control group. Spirulina demonstrated protective effects on lead acetate-induced damage.

Two molecules of deferasirox, an orally administered chelator, binding iron

Two molecules of deferasirox, an orally administered chelator, binding iron

Similar research showed a Spirulina-enriched diet of mother animals alleviates lead-induced damages in brains of newborns and cerebellum tissue damages. A significant decrease in weight and protein content of these tissues was found in newborns birthed by mothers with lead poisoning, but without the Spirulina-enriched diet. Oxidative stress and changes in antioxidant enzyme activities in brain tissues were also recorded. Conversely, no such damages or biochemical changes were found in neonates from Spirulina fed lead-poisoned mothers. These results strongly suggest that beneficial effects of Spirulina-added diet on lead-intoxicated animals.

Why no human studies?

The only human subjects algae treatment study for heavy metals found in the medical literature targeted chronic arsenic poisoning patients in Bangladesh. The fact that no human trials have proven the efficacy of Spirulina, as a lead chelator, does not diminish the probability that the human trials proposed here will succeed.

The reason there are no human studies comes down to one simple word: money. Medical studies are expensive and medical research sponsors want a return on their investment. Medical school faculty members are judged not only on their publications but also on how much they receive in grant support.

Spirulina and other algae species are excellent candidates for lead removal from human tissues but no company wants to sponsor such research. Spirulina is a natural product, freely available on nearly every continent. Therefore, the research will benefit all people because the findings are not protectable. No company can patent a naturally occurring organism.

Nutrient-rich Diet

In addition to the role Spirulina plays as a chelator, Spirulina’s nutritional benefits align with medical expert’s dietary recommendations for those inflicted with bioaccumulated lead in their bodies. Spirulina has been consumed for centuries due to its high nutritional value and substantial health benefits. Spirulina grows naturally in oceans and salty lakes in subtropical climates. The Smart Microfarms site shows how to grow Spirulina in your back yard.

The Aztecs harvested Spirulina from Lake Texcoco in central Mexico hundreds of years ago. For decades, women have harvested Spirulina, which they call Dihé, from Lake Chad in west-central Africa and turn it into dry cakes. Dihé is a rich source of protein, iron and beta-carotene and enhances the nutritional value of diets that are poor in these nutrients. The best Dihé is reserved for pregnant mothers and small children to fight malnutrition. Additional Dihé is sold in markets as a single-source nutritional supplement.

(L) Traditional Dihé harvest on Lake Chad, (R) Dihé ready for market

(L) Traditional Dihé harvest on Lake Chad, (R) Dihé ready for market

Diet plays an important role in curbing lead poisoning. The Minnesota Department of Health recommendations a well balanced diet to moderate lead poisoning. Meals high in fats and oils are not good because they help the body absorb lead. Foods that are rich in calcium (milk or yogurt) and iron (red meat or beans) allow the body to absorb less lead. Eating foods high in Vitamin C (orange juice, tomatoes or dark green leafy vegetables) increases the amount of iron in the blood. Eating a variety of foods as part of a well-balanced diet helps each child grow up healthy and strong.

Spirulina and other algae species absorb a wealth of mineral elements that concentrate as about one third of the dry biomass. The macronutrients include sodium, calcium, magnesium, potassium, chlorine, sulfur, and phosphorus. Essential micronutrients include iodine, iron, zinc, copper, selenium, molybdenum, fluoride, manganese, boron, nickel, and cobalt.

Succulence is the natural ability of succulent plants to absorb and hold water. Spirulina demonstrates “nutralence,” as the biomass concentrates nutrients at substantially higher levels than land plants. One tablespoon, 10 grams of Spirulina delivers the same amount of:

  • Calcium as 8 tbs milk, 32 tbs soybeans, 8 carrots, or 22 tomatoes.
  • Magnesium as 40 tbs milk, 8 tbs soybeans, 9 carrots, or 6 tomatoes.
  • Iron as 512 tbs milk, 8 tbs soybeans, 11 carrots, or 5 tomatoes.

Field studies show that other vitamins and minerals are similarly 100 to 400% denser in Spirulina than in field crop produce, such as tomatoes, beans and dark green leafy vegetables.

Although very low in fat, Spirulina is an excellent source of the essential polyunsaturated fatty acids. The omega-6 and omega-3 fatty acids (ARA and EPA/DHA respectively) are essential for normal metabolism. Omega-3 and 6 are the precursors to critical hormone-like, signaling molecules known as the eicosanoids. These short-lived messengers direct life-supporting functions such as blood clotting, inflammation, vasodilation, blood pressure, and immune function. Only small amounts of ARA and EPA/DHA are needed daily (<1 g), and one tablespoon of Spirulina can supply this amount.

Spirulina pills and power Spirulina smoothie

Spirulina pills and power Spirulina smoothie


A comparison between the leading FDA approved lead chelation treatment using EDTA therapy and Spirulina chelation illustrates key differences.

The CDC notes that ETA therapy depletes the body of essential vitamins and minerals so therapy requires replacement. Spirulina delivers a full set of essential amino acids as well as essential vitamins and minerals so additional infusion is unnecessary. Spirulina is not FDA approved for lead chelation but the literature reflects no human studies or requests for FDA approval.


Spirulina has been used for decades to remove heavy metals, including lead from aqueous solutions and wastewater. River water removal is not an option in Flint. The lead bioaccumulation stems from the excessive iron in river water that leaches lead from the old lead water delivery pipes to homes. No one has invented a home Spirulina water-cleansing unit yet. The Flint lead catastrophe may spark such an invention.

The other limitation is that Spirulina has not been clinically proven to serve as an effective lead chelator for human children or adults. However, Spirulina is a natural product that is sufficient nontoxic that it has been awarded GRAS status, Generally Recognized as Safe, by the FDA. This author wrote the Algae Biomass Organization Technical Standards for Food, Feeds and Nutraceuticals and found no studies showing 500 mg/day Spirulina supplements do anything but benefit people.

People globally have been eating Spirulina safely for centuries. Therefore, the major risk in the proposed human trials for Spirulina as a lead chelator is that the theoretical arguments presented here fail in real life. Solid science naturally presents the risk of failure, which is why scientists conduct tests and studies. Positive findings may save many children’s precious brains and bodies and improve the lives of many families.

Path forward

Spirulina appears to offer a simple, safe and inexpensive solution for reducing the lead currently locked in the brains of Flint, Michigan children and adults. Two daily doses of 250 mg of Spirulina should act as an effective biosorbent and chelate with the lead and allow it to pass harmlessly out of the body in the urine.

I believe this Spirulina will serve as an effective chelator for lead poisoning but do not have the resources or the medical credentials to prove efficacy. I will provide the Spirulina free (500 mg/day per child) to any physician who will perform a double blind test to assess how much lead Spirulina removes from children over 16 weeks.

Please contact Mark Edwards, Emeritus Professor, Strategic Marketing and Sustainability, Arizona State University, at: