What Is Calcium Disodium EDTA, and Is It Safe?

Calcium disodium EDTA is a chemical compound that can trap and remove heavy metals, both from your body and from things like food, paper, shampoo and cosmetics.

"It's a particularly versatile compound, says Christopher Cramer, PhD, chief research officer at Underwriters Laboratories. "It's a great compound for taking metals out of circulation."

Here, we'll look more closely at how it's used, its potential risks and side effects and whether it's safe.

First synthesized in 1935, calcium disodium EDTA (ethylene-diaminetetraacetate) is a chelating agent, which is a compound that binds to and removes metals. It appears as a yellow/brown powder and has no odor, according to the European Food Safety Authority.

It's often found under the brand name Calcium Disodium Versenate, according to the Cleveland Clinic.

Calcium disodium EDTA acts very differently in the human body depending on whether it's injected or ingested. If it's swallowed, it's poorly absorbed, Cramer says.

Your body absorbs it much better when it's injected — in a muscle or, more often, through a vein.

Calcium disodium EDTA has two main uses in human health, both of which derive from its ability to trap metals. One is to treat severe lead poisoning while the other is as an additive in food.

The main medical use of calcium disodium EDTA is to treat severe, life-threatening lead poisoning.

"These are really high levels where people have neurological impairment and are potentially comatose," says Kaitlyn Brown, PharmD, clinical managing director of the American Association of Poison Control Centers.

Calcium disodium EDTA is typically administered with another compound called dimercaprol (British antilewisite or BAL). While calcium disodium EDTA is good at getting lead out of the bone and hard tissue, BAL goes after lead in the soft tissue, Brown explains.

Both are usually injected into patients who are already hospitalized and who represent a small percentage of all lead-poisoning cases. "These patients are typically the sickest of the sick," says Brown.

Doctors usually administer the drugs over a five-day period to make sure the lead is completely removed, she adds.

Doctors treat less-severe cases of lead poisoning, which may include symptoms like abdominal pain, constipation, fatigue, weakness and headaches, with a drug called succimer, says Brown.

Severe cases of lead poisoning develop over time as blood levels rise gradually with ongoing exposure to the metal. It can be inhaled or ingested and can lead to development issues in learning and behavior, especially in small children.

In the food industry, calcium disodium EDTA scavenges for and removes trace amounts of metal that accumulate in the process of food preparation.

Rollers, containers and other aspects of food processing involve a lot of metals, which can end up in the food, says Debbie Petitpain, RDN, LDN, a spokesperson for the Academy of Nutrition and Dietetics.

Even tiny amounts of metal can spoil food faster, especially those containing fats. This process, called rancidity, happens when fats and oils are exposed to elements like oxygen, light and moisture. You'll know it when you smell it.

"If olive oil has been out on the countertop, it can smell 'off,'" says Petitpain. "That's rancidity. It's a breaking-down process when something is exposed to air, and trace metals make that worse."

Calcium disodium EDTA acts as a preservative and also helps products retain their color.

The Food and Drug Administration (FDA) has approved the use of calcium disodium EDTA in limited amounts in many different processed foods, including:

• Canned carbonated soft drinks
• Pickled cucumbers and cabbage
• Canned beans
• Distilled alcoholic beverages
• French dressing
• Mayonnaise
• Salad dressing

Only about 5 percent of calcium disodium EDTA is absorbed by your body when it's a food additive. The rest quickly leaves your body, making side effects unusual. "The quantity put into food products is also far less than quantities given for metal chelation," says Brown.

"There are no potential risks," says Petitpain. It passes through the body quickly, she says, adding that the actual rate depends on what you're eating.

When injected to treat lead poisoning, though, calcium disodium EDTA can have the following side effects:

This is the main risk when the compound is taken as a medicine. "It can be hard on the kidneys and you could have renal failure," Cramer says.

The metal chelate that's formed when the lead and calcium disodium EDTA merge can get caught up in the tubes of the kidney, but that's typically reversible once the therapy is stopped, says Brown.

Given how serious lead poisoning can be, "it's definitely in the interest of people to have this if it's indicated."

When used as a drug, calcium disodium EDTA may also result in less severe side effects, such as:

• Muscle aches
• Chills
• Fever
• Headache
• Nausea or vomiting
• Dark or cloudy urine, or trouble urinating
• Numbness and tingling
• Fatigue
• Racing heart beat
• Allergic reactions like hives, swelling, itching or rash

According to the Cleveland Clinic, calcium disodium EDTA can interact with:

• Steroids such as prednisone or cortisone
• Insulin with zinc
• Zinc salts

When it comes to food, calcium disodium EDTA poses few dangers because it is present in such low amounts to begin with and because very little is absorbed by the body.

"It's present in really small concentrations, so the likelihood of you ingesting a reasonable amount by absorbing it through your gut is vanishingly small," says Cramer.

It has also been used in the food supply for a long time, adds Petitpain.

If you're concerned about food safety, you can avoid calcium disodium EDTA and other additives by staying away from processed foods and focusing instead on fresh fruits and vegetables, whole grains and lean proteins, says Petitpain.

There is the possibility of kidney failure when it's taken as a drug, but the alternative would be severe lead poisoning, which can be fatal. "It's a case of 'pick your poison,'" Cramer says.