There’s Ferrocyanide in Our Food. What Should We Do About It?
The answer is simple: we should learn more about the compound before we freak out over another clickbait title like this one. Good thing you’re here.
What is Ferrocyanide and why is in our food?
Ferrocyanide is a salt ion and comes mainly in three forms as a food additive: Sodium ferrocyanide, potassium ferrocyanide, and calcium ferrocyanide, with the first form being the most common. Although many salts of cyanide are highly toxic, food-grade forms of ferrocyanide are far less toxic because they do not release free cyanide.
Ferrocyanide is an odorless yellow solid that mixes with water and is used mainly as an anticaking agent. In this way, it is often added to food grade salt to prevent lumping as well as make sure it’s dispensed smoothly through a salt shaker.
Are Ferrocyanides dangerous?
Acute oral toxicity is roughly 5 g/kg body weight or 350 g for a 70 kg human. Despite the presence of cyanide, it is tightly bound (with ions) and stays within its atom until excretion. The range of its use in salt, salt substitutes, and seasonings and condiments are from 14 mg/kg to 20 mg/kg of the product. In other words, these additives are in salts seasonings, condiments— and several other common products that contain salt. It also means that you would have to eat a significant amount of table salt to reach the toxic level, and even then it would be the salt—not the ferrocyanide—that would ultimately kill you.
Arguments against the use of ferrocyanide in food
The main argument against ferrocyanide in our food is that it sounds scary. The second argument against it is that it’s hazardous in case of direct ingestion, skin contact, eye contact, and even inhalation. But that is when directly exposed to the pure substance— not when ingested through dietary means. In other words, if found in a laboratory, do not consume, do not put in your eyes, and do not inhale this solid. If you screw this up, follow the instructions provided on the Material Safety Data Sheet (MSDS).
Common Substitutes for ferrocyanide in food
Natural anticaking agent substitutes include magnesium silicate, silicon dioxide, potato starch, tapioca starch, and cornstarch.
1. Inchem.org. (2018). 258. Calcium, potassium, sodium ferrocyanide (WHO Food Additives Series 5). [online] Available at: http://www.inchem.org/documents/jecfa/jecmono/v05je02.htm [Accessed 8 Jun. 2018].
2. Fao.org. (2018). GSFA Online Food Additive Group Details for FERROCYANIDES. [online] Available at: http://www.fao.org/gsfaonline/groups/details.html?id=242 [Accessed 8 Jun. 2018].
3. Sciencelab.com. (2018). [online] Available at: [Accessed 8 Jun. 2018].
4. Publications.lib.chalmers.se. (2018). [online] Available at: http://publications.lib.chalmers.se/records/fulltext/239315/239315.pdf [Accessed 8 Jun. 2018].