Tape tied vegetables, formaldehyde exceeded 10 times? It's not so scary. It's more real

1. Tape is indeed a gray area, "food grade" tape does not exist.

2. Authoritative tests show that the formaldehyde residue in the tape is not terrible. At present, there is no standard limit for formaldehyde residue in food, and the statement that "formaldehyde exceeds the standard by 10 times" in the news is unreliable.

3. There is natural formaldehyde in food, and formaldehyde has strong water solubility and volatility. If you are too worried about sticky tape dishes, process or dispose of them.

In supermarkets and farmers markets, vegetables are often bundled into small bundles. On the one hand, bundling vegetables is convenient for you to buy. On the other hand, it also prevents "smart" aunts and uncles from picking too much. In the past, straw rope was often used to bind vegetables. In recent years, colorful tape has become more and more common. Compared with straw rope, tape is not only beautiful and generous, but also cleaner. However, it is widely rumored on the Internet that the tape used to bind vegetables is toxic, and its formaldehyde exceeds 10 times the standard. Long term consumption of such vegetables may cause cancer. Should we avoid vegetables tied with tape when we buy vegetables in the future?

Food tied with tape is very common

What is the tape

The tape used to bind vegetables is similar to the transparent glue usually used. In fact, it is a plastic film coated with adhesive. The most common plastic film is BOPP (biaxially oriented polypropylene), but also PVC (polyvinyl chloride), pet (polyethylene terephthalate), PE (polyethylene) and other materials. There are many kinds of adhesives, but the most used is pressure-sensitive acrylate ①.

The tape is indeed a gray area

Tape is not food, but it is in direct contact with food. Therefore, Adhesive Tape it should also comply with the provisions of food safety law and relevant food safety standards. For example, GB / t10004-2008 ② puts forward requirements for the quality and impurities of plastic film used for tape, and gb9685-2016 ③ imposes corresponding restrictions on the additives used in tape adhesive. Therefore, strictly speaking, the tape produced according to the specifications will not have much safety problem.

However, plastic film and adhesive are added together to make tape, but there is no special product standard, that is, there is no "food grade" tape. Of course, even if there is "food grade" tape, I believe many vendors will use ordinary tape for cost reasons.

Tape formaldehyde data

Plastic film and adhesive are polymers, which are very stable under natural conditions, Adhesive Tape and there is little possibility of degrading and releasing a large amount of formaldehyde. In the production process of plastic film and adhesive, due to incomplete polymerization or incomplete solvent volatilization, a small amount of formaldehyde, benzene and other small molecules may remain. However, the tape used for vegetable binding is only a narrow one. How much residue can it have?

Although this is only rational speculation, some institutions happen to have data to verify. For example, Shenzhen Quality Inspection Institute tested 11 vegetable and tape samples, of which formaldehyde was not detected in the contact parts between vegetables and tape. Although trace formaldehyde was detected in the tape, the premise was to soak it in 60 ℃ acetic acid for 2 hours, which obviously could not happen on vegetables. A reporter from the Beijing News conducted a similar experiment, and formaldehyde was not detected in the parts of three kinds of vegetable tape. Some third-party organizations can verify this result, so in general, the formaldehyde residue in the tape is not terrible.

Incidentally, I don't know where the "formaldehyde exceeding 10 times" in the news comes from, because there is no standard limit for formaldehyde residue in food. If you refer to other relevant standards, "exceeding 10 times" is also unimaginable.

Data source: test data of Shenzhen Quality Inspection Institute ④

What should consumers do

In 2013, "vegetables bound with tape" attracted widespread attention after media reports. Later, government departments in Ningbo, Zhejiang, Harbin, Heilongjiang and Yinchuan, Ningxia ordered to ban tape. Some supermarkets use straw rope or plastic wrap, but because the tape is too easy to use, it is still very popular in farmers' markets and small vegetable stalls.

In fact, consumers don't have to worry too much, because formaldehyde is very water-soluble and volatile, which is difficult to accumulate on the surface of vegetables. Even if there is a small amount of residue, it will disappear in the process of picking, washing and frying. If you are really worried, Adhesive Tape you should be relieved to directly cut off the contact part of the tape?

If you don't feel at ease... I can only tell you that fruits and vegetables generally contain trace amounts of formaldehyde, generally 3-60 mg per kilogram. There will also be trace amounts of natural formaldehyde in meat, fish, crustaceans and milk. 

For example, the formaldehyde (non-human addition) content of squid can reach more than 100 mg per kg. If you eat a bag Adhesive Tape of squid shreds (100 g), it is equivalent to the size of 8 pieces of A4 paper. Still worried?