Is there an extermination plan against the Chinese in table salt? Salt: I won't take the blame

Author: Ruan Guangfeng

The article comes from the Science Academy official account (ID: kexuedayuan)

Chinese people pay attention to the color, aroma and taste of food, and salt is naturally indispensable. However, there is always a "truth" that is constantly flooding the WeChat Moments: China National Salt Corporation adds a "drug" called potassium ferrocyanide to table salt. It is for industrial use and can cause unexplained death. Potassium ferrocyanide is a conspiracy by China National Salt Corporation and American companies to destroy the Chinese. Europeans and Americans do not eat it themselves, but only recommend it to other countries.

(Image source: Internet)

What exactly is potassium ferrocyanide? Is it really found in table salt? Can we really eat salt without worry?

What is potassium ferrocyanide?

Is there any relationship between potassium ferrocyanide and the highly toxic substance potassium cyanide that we often hear about?

Potassium ferrocyanide is also called potassium ferrocyanide, and its chemical formula is

K4[Fe(CN)6], while the chemical formula of potassium cyanide is KCN. The difference between the two is that the cyanide and iron elements in potassium ferrocyanide are firmly combined, so its acute toxicity is hundreds of times lower than that of potassium cyanide.

The median lethal dose (LD50) of potassium ferrocyanide is about 1.6-3.2 grams per kilogram of body weight, which is very close to the table salt we often eat and is also a low-toxic substance. However, potassium cyanide is a highly toxic substance that will kill you if you ingest it.

Therefore, potassium ferrocyanide and potassium cyanide have nothing in common except for their similar names, and their toxicity is even more different.

What is potassium ferrocyanide used for?

In fact, potassium ferrocyanide is added to table salt as an anti-caking agent.

National standards stipulate that potassium ferrocyanide is an anti-caking agent (picture from GB2760)

Anticaking agents are often used in powdered foods such as salt, milk powder, cocoa powder, and coffee powder to prevent powdered foods from clumping. Potassium ferrocyanide is easily soluble in water and is colorless. A small amount can achieve a good anticaking effect, so it is widely used. In addition to potassium ferrocyanide, other commonly used anticaking agents in salt include silicon dioxide, calcium silicate, and ammonium ferric citrate.

(Image source: orsoon.com)

How safe is potassium ferrocyanide?

After all, what people are most worried about is the safety of potassium ferrocyanide. In fact, potassium ferrocyanide is very stable and will not decompose even when added to salt during cooking or high-temperature cooking.

At the same time, the binding force between cyanide and iron in potassium ferrocyanide is very strong, and cyanide is difficult to detect even in a potassium ferrocyanide solution.

Theoretically, potassium ferrocyanide can decompose to produce potassium cyanide at high temperatures, but the temperature must be at least 400 degrees, and the temperature of ordinary household cooking cannot reach such a high level.

You know, when we cook at temperatures over 200 degrees, a lot of oil smoke starts to appear, and the coating on the non-stick pan starts to melt at 330 degrees. If it really reaches 400 degrees, can you still enjoy your meal?

It is better to be safe than sorry! Some people always think: what if it really decomposes into potassium cyanide? Putting aside the worry about toxicity, it is just scaring yourself! Let's do some calculations.

It takes more than 0.1 gram of potassium cyanide to poison an adult, but there is only 0.01 gram of potassium ferrocyanide in 1 kilogram of salt. Even if you "magically" decompose all the potassium ferrocyanide, you would have to eat more than ten kilograms of salt to be poisoned!

Would you eat that much salt? Even if you could, you would probably choke to death.

The Ministry of Health also responded to potassium ferrocyanide (Photo from: China News Network)

Some people are still worried. If I take a little bit every day, will it be chronically toxic? Will it cause cancer?

In fact, the chronic toxicity of potassium ferrocyanide is also very low. According to data from the World Health Organization and the Food and Agriculture Organization of the United Nations, the lifetime safe dose of potassium ferrocyanide is 0.025 mg per kilogram of body weight. In other words, for a 60-kilogram person, consuming 1.5 mg per day is completely fine. However, my country's national standards stipulate that the maximum amount of potassium ferrocyanide added to table salt is 10 mg per kilogram. If you want to eat it and get sick, a 60-kilogram person must eat at least 3 taels of salt every day.

You should know that my country's dietary guidelines recommend that the daily salt intake should not exceed 6 grams. If you really eat 3 taels of salt every day, you will probably choke to death. Moreover, eating too much salt will increase the risk of cardiovascular diseases such as high blood pressure and stroke.

Don’t foreigners use potassium ferrocyanide?

Do foreigners really not use potassium ferrocyanide? Is adding potassium ferrocyanide to table salt really a plan to exterminate other countries?

In fact, potassium ferrocyanide is also used as an anticaking agent in foreign countries. The Codex Alimentarius Commission, the European Union, the United States, Japan, Australia and New Zealand all allow potassium ferrocyanide to be used as a food additive.

EU Directive 95/2/EC stipulates that the maximum allowable amount of potassium ferrocyanide as a food additive is 20 mg/kg (calculated as anhydrous potassium ferrocyanide). The US Food and Drug Administration stipulates that the maximum amount of potassium ferrocyanide allowed in table salt is 13 mg/kg. The Australian and New Zealand Food Standards Agency stipulates that the MPL (Maximum Permitted Level) of potassium ferrocyanide as a food additive is 50 mg/kg.

So, who says Americans don’t use potassium ferrocyanide?

A type of salt sold abroad, the anti-caking agent in it is also potassium ferrocyanide. (Image source: attheitaliantable.com)

In short, potassium ferrocyanide is safe to use in table salt, and there is no need to worry if you eat salt in moderation. Here is a special reminder: please pay attention to the appropriate amount of salt. Excessive sodium intake will increase the risk of cardiovascular diseases such as high blood pressure. However, the problem that causes disease risk is salt, not anti-caking agents.