Chlorohydrin contaminates hydrolyzed vegetable protein products and refined oils.
The Side Effects of 3-MCPD in Bragg’s Liquid Aminos
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Intro: You may see the title of this video and be thinking…what is 3-MCPD? It’s a chlorohydrin, a compound found in items like Bragg’s liquid aminos and soy sauce. Is it safe? Watch to find out.
In 1978, chlorohydrins were found in protein hydrolysates. What does that mean? Proteins can be broken down into amino acids using a chemical process called hydrolysis, and free amino acids like glutamate can have taste-enhancing qualities. That’s how they make cheap soy sauce and seasonings like Bragg’s liquid aminos. This process requires high heat, high pressure, and hydrochloric acid to break apart the protein. The problem is that when any residual fat is exposed to these conditions, it can form toxic compounds called chlorohydrins. But when I say toxic, we’re talking about toxic to mice and rats.
Chlorohydrins like 3-MCPD are considered a worldwide problem of food chemistry, but no clinical studies on humans have been reported so far. The concern is about detrimental effects on kidneys and fertility. In fact, there was a time in which it was considered as a potential male contraceptive because it could so affect sperm production. However, research funding was withdrawn after unacceptable side effects were observed in primates. They found flaccid testes in rats, which is what they were going for, but it caused neurological scars in monkeys.
What do you do, though, when there are no studies in humans? How do you set some kind of safety factor? Well, it’s not easy. What you do is take the lowest-observed-adverse-effect level in animal studies, which in this case was kidney damage, then add in some kind of fudge factor, and arrive at an estimated tolerable daily intake, which for 3-MCPD means that high level consumers of soy sauce may exceed the limit. But this was based on extraordinarily high contamination levels. Since then, Europe introduced a regulatory limit of 20 parts per billion of 3-MCPD in hydrolyzed vegetable protein products like liquid aminos and soy sauce. The U.S. standards are much laxer, though, allowing 50 times more—1,000 parts per billion.
I called Bragg to see where they fell, and the good news is that they are doing independent third-party analysis of their liquid aminos for 3-MCPD. The bad news is that despite my pleas that they be fully transparent, they wouldn’t let me share the results with you. I have seen them, though, but I’m only allowed to confirm they comfortably meet the U.S. standards, but fail the European standards.
This is just the start of the 3-MCPD story, though. If you test people’s urine for 3-MCPD or its metabolites, 100 percent of people turn up positive, confirming that it’s a widespread food contaminant. But 100 percent of people aren’t downing soy sauce or liquid aminos every day. But remember, the chemical resulted from a reaction with residual vegetable oil. When vegetable oil itself is refined, when it’s deodorized and bleached, those conditions also lead to the formation of 3-MCPD.
And indeed, we’ve known for years that various foods are contaminated. In what kind of foods have these kinds of chemicals been detected? Well, if it’s in the oils and fats, then it’s in the greasy foods made from them: margarine, baked goods, pastries, deep-fried foods, fatty snacks like potato and corn chips, as well as infant formula.
Here’s the FDA limit is for soy sauce, 1,000. But doughnuts can have more than 1,200, salami more than 1,500, ham nearly 3,000, and French fries in excess of 6,000.
So most people don’t have to worry about this problem, unless you’re a consumer of fried food. For example, someone weighing about 150 pounds who eats 116 grams of doughnuts would exceed the maximum tolerable daily intake, even if that was their only source of exposure. Now, that’s about two doughnuts. But the same limit-blowing amount of 3-MCPD could be found in only five French fries.
Please consider volunteering to help out on the site.
- Velísek J, Davídek J, Hajslová J, Kubelka V, Janícek G, Mánková B. Chlorohydrins in protein hydrolysates. Z Lebensm Unters Forsch. 1978;167(4):241-4.
- Jędrkiewicz R, Kupska M, Głowacz A, Gromadzka J, Namieśnik J. 3-MCPD: A Worldwide Problem of Food Chemistry. Crit Rev Food Sci Nutr. 2016;56(14):2268-77.
- Bakhiya N, Abraham K, Gürtler R, Appel KE, Lampen A. Toxicological assessment of 3-chloropropane-1,2-diol and glycidol fatty acid esters in food. Mol Nutr Food Res. 2011;55(4):509-21.
- Heywood R, Sortwell RJ, Prentice DE. The toxicity of 1-amino-3-chloro-2-propanol hydrochloride (CL88,236) in the rhesus monkey. Toxicology. 1978;9(3):219-25.
- Tritscher AM. Human health risk assessment of processing-related compounds in food. Toxicol Lett. 2004;149(1-3):177-86.
- EFSA Panel on Contaminants in the Food Chain (CONTAM), Knutsen HK, Alexander J, et al. Update of the risk assessment on 3-monochloropropane diol and its fatty acid esters. EFSA J. 2018;16(1):e05083.
- Larsen JC. 3-MCPD esters in food products. Brussels: ILSI Europe; 2009.
- Food and Drug Administration Office of Regulatory Affairs, Center for Food Safety and Applied Nutrition. CPG Sec. 500.500 Guidance Levels for 3-MCPD(3-chloro-1,2-propanediol) in Acid-Hydrolyzed Protein and Asian-Style Sauces. Issued: March 14, 2008.
- Andreoli R, Cirlini M, Mutti A. Quantification of 3-MCPD and its mercapturic metabolite in human urine: validation of an LC-MS-MS method and its application in the general population. Anal Bioanal Chem. 2015;407(16):4823-7.
- Svejkovska B, Novotny O, Divinova V, Réblová Z, Doležal M, Velisek J. Esters of 3-chloropropane-1,2-diol in foodstuffs. Czech J Food Sci. 2004;22:190-6.
- BfR, Bundesinstitut für Risikobewertung. Frequently asked questions regarding the contamination of foods with 3-MCPD, 2-MCPD and glycidyl fatty acid esters. BfR, Bundesinstitut für Risikobewertung website. July 7, 2016.
- Arisseto AP, Marcolino PF, Vicente E. 3-Monochloropropane-1,2-diol fatty acid esters in commercial deep-fat fried foods. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2015;32(9):1431-5.
Video production by Glass Entertainment
Motion graphics by Avo Media
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Intro: You may see the title of this video and be thinking…what is 3-MCPD? It’s a chlorohydrin, a compound found in items like Bragg’s liquid aminos and soy sauce. Is it safe? Watch to find out.
In 1978, chlorohydrins were found in protein hydrolysates. What does that mean? Proteins can be broken down into amino acids using a chemical process called hydrolysis, and free amino acids like glutamate can have taste-enhancing qualities. That’s how they make cheap soy sauce and seasonings like Bragg’s liquid aminos. This process requires high heat, high pressure, and hydrochloric acid to break apart the protein. The problem is that when any residual fat is exposed to these conditions, it can form toxic compounds called chlorohydrins. But when I say toxic, we’re talking about toxic to mice and rats.
Chlorohydrins like 3-MCPD are considered a worldwide problem of food chemistry, but no clinical studies on humans have been reported so far. The concern is about detrimental effects on kidneys and fertility. In fact, there was a time in which it was considered as a potential male contraceptive because it could so affect sperm production. However, research funding was withdrawn after unacceptable side effects were observed in primates. They found flaccid testes in rats, which is what they were going for, but it caused neurological scars in monkeys.
What do you do, though, when there are no studies in humans? How do you set some kind of safety factor? Well, it’s not easy. What you do is take the lowest-observed-adverse-effect level in animal studies, which in this case was kidney damage, then add in some kind of fudge factor, and arrive at an estimated tolerable daily intake, which for 3-MCPD means that high level consumers of soy sauce may exceed the limit. But this was based on extraordinarily high contamination levels. Since then, Europe introduced a regulatory limit of 20 parts per billion of 3-MCPD in hydrolyzed vegetable protein products like liquid aminos and soy sauce. The U.S. standards are much laxer, though, allowing 50 times more—1,000 parts per billion.
I called Bragg to see where they fell, and the good news is that they are doing independent third-party analysis of their liquid aminos for 3-MCPD. The bad news is that despite my pleas that they be fully transparent, they wouldn’t let me share the results with you. I have seen them, though, but I’m only allowed to confirm they comfortably meet the U.S. standards, but fail the European standards.
This is just the start of the 3-MCPD story, though. If you test people’s urine for 3-MCPD or its metabolites, 100 percent of people turn up positive, confirming that it’s a widespread food contaminant. But 100 percent of people aren’t downing soy sauce or liquid aminos every day. But remember, the chemical resulted from a reaction with residual vegetable oil. When vegetable oil itself is refined, when it’s deodorized and bleached, those conditions also lead to the formation of 3-MCPD.
And indeed, we’ve known for years that various foods are contaminated. In what kind of foods have these kinds of chemicals been detected? Well, if it’s in the oils and fats, then it’s in the greasy foods made from them: margarine, baked goods, pastries, deep-fried foods, fatty snacks like potato and corn chips, as well as infant formula.
Here’s the FDA limit is for soy sauce, 1,000. But doughnuts can have more than 1,200, salami more than 1,500, ham nearly 3,000, and French fries in excess of 6,000.
So most people don’t have to worry about this problem, unless you’re a consumer of fried food. For example, someone weighing about 150 pounds who eats 116 grams of doughnuts would exceed the maximum tolerable daily intake, even if that was their only source of exposure. Now, that’s about two doughnuts. But the same limit-blowing amount of 3-MCPD could be found in only five French fries.
Please consider volunteering to help out on the site.
- Velísek J, Davídek J, Hajslová J, Kubelka V, Janícek G, Mánková B. Chlorohydrins in protein hydrolysates. Z Lebensm Unters Forsch. 1978;167(4):241-4.
- Jędrkiewicz R, Kupska M, Głowacz A, Gromadzka J, Namieśnik J. 3-MCPD: A Worldwide Problem of Food Chemistry. Crit Rev Food Sci Nutr. 2016;56(14):2268-77.
- Bakhiya N, Abraham K, Gürtler R, Appel KE, Lampen A. Toxicological assessment of 3-chloropropane-1,2-diol and glycidol fatty acid esters in food. Mol Nutr Food Res. 2011;55(4):509-21.
- Heywood R, Sortwell RJ, Prentice DE. The toxicity of 1-amino-3-chloro-2-propanol hydrochloride (CL88,236) in the rhesus monkey. Toxicology. 1978;9(3):219-25.
- Tritscher AM. Human health risk assessment of processing-related compounds in food. Toxicol Lett. 2004;149(1-3):177-86.
- EFSA Panel on Contaminants in the Food Chain (CONTAM), Knutsen HK, Alexander J, et al. Update of the risk assessment on 3-monochloropropane diol and its fatty acid esters. EFSA J. 2018;16(1):e05083.
- Larsen JC. 3-MCPD esters in food products. Brussels: ILSI Europe; 2009.
- Food and Drug Administration Office of Regulatory Affairs, Center for Food Safety and Applied Nutrition. CPG Sec. 500.500 Guidance Levels for 3-MCPD(3-chloro-1,2-propanediol) in Acid-Hydrolyzed Protein and Asian-Style Sauces. Issued: March 14, 2008.
- Andreoli R, Cirlini M, Mutti A. Quantification of 3-MCPD and its mercapturic metabolite in human urine: validation of an LC-MS-MS method and its application in the general population. Anal Bioanal Chem. 2015;407(16):4823-7.
- Svejkovska B, Novotny O, Divinova V, Réblová Z, Doležal M, Velisek J. Esters of 3-chloropropane-1,2-diol in foodstuffs. Czech J Food Sci. 2004;22:190-6.
- BfR, Bundesinstitut für Risikobewertung. Frequently asked questions regarding the contamination of foods with 3-MCPD, 2-MCPD and glycidyl fatty acid esters. BfR, Bundesinstitut für Risikobewertung website. July 7, 2016.
- Arisseto AP, Marcolino PF, Vicente E. 3-Monochloropropane-1,2-diol fatty acid esters in commercial deep-fat fried foods. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2015;32(9):1431-5.
Video production by Glass Entertainment
Motion graphics by Avo Media
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The Side Effects of 3-MCPD in Bragg’s Liquid Aminos
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Content URLDoctor's Note
Believe me, I pled with the Bragg’s folks over and over. It’s odd to me that they allowed me to talk about where their level of 3-MCPD fell compared to the standards, but not say the number itself. At least they’re doing third-party testing.
Stay tuned for the next video 3-MCPD in Refined Cooking Oils.
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