Popular Science | How to choose socks? Beware of carcinogens!

According to a report by CCTV Finance Channel on August 23, 2021, the Jiangsu Provincial Market Supervision Bureau sampled 95 batches of socks and found that 16 batches were unqualified, some of which were sold by e-commerce or live streaming platforms. The reasons for the failure include fiber content, benzidine (dye) content and other indicators. For example, the benzidine content exceeded 70mg/kg, far exceeding the qualified line of 20mg/kg. Benzidine is a Class I carcinogen recognized by the International Agency for Research on Cancer (IARC). Excessive benzidine content poses a major safety hazard to human health.

So how do you choose socks?

In order to avoid buying unqualified socks, you should pay attention to the following when choosing socks:

1. Look at the material

There are many varieties of socks on the market, and the materials are also varied. Generally speaking, pure cotton is better. The cotton content of pure cotton socks is generally 70%~95%, and other ingredients are 15%~30% elastic fiber (such as spandex, nylon), etc.; when choosing the material, you should also consider the actual wear. For example, people with sweaty feet should choose cotton socks with good breathability and moisture permeability, and people with cracked feet should choose polypropylene or nylon socks with slightly lower breathability and moisture absorption.

2. Look at the label

Check the labels on the socks to see if the trademark, factory name and address, ingredient markings, washing instructions, certificate of conformity, implementation standard number, etc. are complete. Qualified socks should have complete and standardized markings.

3. Look at the thickness

When buying socks, in order to ensure comfort, you should choose socks of different thicknesses according to the season. Some stockings bags will be marked with a "D" value. D (denier) is the abbreviation of "Denier", which is an indicator of fiber fineness. The larger the D value, the thicker the yarn and the thicker the socks. For example, stockings, under normal circumstances, have a D value of less than 5 denier for ultra-thin stockings, less than 20 denier for summer socks, 40 denier to 60 denier for spring and autumn socks, and greater than 60 denier for winter socks.

4. Smell

When buying socks, smell them to see if there is a pungent smell. If there is a pungent smell, the formaldehyde or pH value may exceed the standard. Be careful when buying such socks.

5. Look at the matching

Socks are not only used to keep warm, but also an important element in the overall clothing matching. The color and pattern of socks should be coordinated with clothing and shoes, for example: light-colored clothing should be matched with plain socks, and dark socks should be matched with dark clothing.

6. Touch quality

Socks made of different materials have different feel, for example, cotton socks feel plump and soft; chemical fiber socks feel smooth; touch the toe of the sock, which is an important part that affects the comfort of the socks. If the toe is too tight, it will easily cause a sense of pressure on the foot and affect blood circulation in the foot; also look at the sewing process of the toe of the sock, the seam of the toe should generally be smooth. If there are protruding seams when touched, it is easy to cause marks; touch the sock opening, the sock opening should be moderately tight. If the sock opening is too loose, it will easily slip off when worn, and if the sock opening is too tight, it will easily affect blood circulation.

7. Choose the right purchasing channel

Whether you buy socks online or in a physical store, you should choose socks produced by regular manufacturers with standard labels to avoid buying products without any labels. After buying socks, you should first wash them to remove odors and impurities. If the socks are severely discolored during washing or the odor is still strong after washing, it is not recommended to wear them.

Nowadays, there are more and more types of socks on the market, which makes people dizzy. In order to avoid falling into the trap of "toxic socks", we must open our eyes, learn the skills to distinguish the quality of socks, and buy safe and comfortable socks.

Author: Ding Lijin, Senior Engineer, Suzhou Fiber Inspection Institute

Bai Jie Director of the Science Popularization Department of China Textile Engineering Society