Junhuiteng Technology Information Center: Recently, experimenters numbered the samples of colored clay and clay, and used heavy metal detection instruments (XD-8010) to detect the samples.

Experimental location: Laboratory of Natural Science University

Experimental samples: 19 types of colored clay and clay samples were purchased through supermarkets, stationery stores, small commodity markets, online stores, and other channels. Among them, 13 types of colored clay samples; 6 types of clay samples.

Colorful clay and clay that can be molded into dolls have gradually become the "new favorite" of children. Since the start of the school season, colored clay from stationery stores around the school has also been selling well.

However, the 2015 quality analysis report on the risk monitoring of colored clay products recently released by the Jiangsu Provincial Quality Supervision Bureau showed that 62 out of 100 monitored samples exceeded the relevant standard limit requirements, mainly due to excessive levels of transferable elements and preservatives.

What is the quality of colored clay and clay? Reporters found that many colored clay and clay are currently "three no" products, directly packaged in transparent plastic bags without indicating the manufacturer, raw materials, expiration date, and other information.

The reporter also purchased 19 samples of colored clay and clay from supermarkets, stationery stores, online stores, etc., with prices ranging from 3 yuan to 35 yuan. According to testing by an environmental protection public welfare organization laboratory in Beijing, 11 of the 19 samples exceeded the standard for barium element, with a pass rate of about 40%; At the same time, chlorine was detected in 5 samples; Two samples detected titanium element; Iron element was detected in one sample.

An industry insider said that the barium element in the colored clay may have been added to a chemical compound called Lide powder, which is used to increase color intensity. Children who come into contact with this substance may cause skin allergies, redness, and itching.

Junhuiteng Technology reminds that heavy metal barium can alter the permeability of cell membranes, and its enrichment may affect cardiovascular health. When purchasing colored clay, avoid buying "three no" products, and children should wash their hands promptly after using colored clay. When purchasing children's toys, it is important to pay attention to the manufacturer's qualifications and try to find larger factories to produce toys, as they have RoHS (heavy metal) detectors, benzene testers, formaldehyde testers, and other testing equipment to ensure product quality throughout the entire process.

Experiment 1

Barium element exceeds the standard by more than ten times

The experimenters prepared 19 types of colored clay and clay samples, each with an area of 6 square centimeters. The colored clay samples were wrapped in PE plastic wrap and numbered. Align the heavy metal detection instrument with the sample and measure the heavy metal content of 19 different samples. Wait for about 30 seconds and observe the test results. The results showed that out of 19 samples, a total of 13 samples detected the heavy metal barium element, with the highest value reaching 3188mg/kg. Meanwhile, chlorine was detected in 5 samples, with the highest value being 9077mg/kg; Two samples were detected to contain titanium, with the highest value being 1851mg/kg.

According to the experimental technicians, the current national standards that can be referenced for colored clay and clay are GB6675-2003 "National Technical Specification for Toy Safety" and QB/T2960-2008 "Industry Standard for Colored Clay Light Industry". According to the requirements, the content of transferable element barium in toys made of clay and finger painting pigments should not exceed 250mg/kg. Chlorine and titanium are not within the range of transferable elements in the national standard.

According to the national standard, 11 out of 19 samples exceeded the standard for barium element, with the highest exceeding the standard by more than ten times.

Eight samples showed slight staining

After unpacking 19 types of colored clay and clay samples, the reporter sniffed the odors of the samples and found that 15 of them had obvious odors, of which 9 were strong aromatic odors; Six types of pungent odors with a slight odor.

At the same time, the reporter directly touched the sample with their fingers, simulating children using colored clay to make dolls for more than 3 minutes, and observed whether there was any staining phenomenon.

It was found that 8 of the samples had slight staining on the fingers. The reporter noticed that these 8 samples are all colored clay and clay priced below 15 yuan.

■ Follow up

Where does heavy metal barium come from?

Will additives that may cause allergies in children be used in the production process of colored clay and clay?

A staff member from a toy manufacturer in Dongguan, Guangdong, explained that regular manufacturers usually strictly follow the current national and enterprise standards when making colored clay and toys, and do not use additives that may cause allergies in children.

However, due to the uneven quality of various brands in the current clay industry, some companies use an additive called Lide powder to reduce costs and compete at low prices. It is a mixture of zinc sulfide and barium sulfate, which can make the color of clay and clay more vibrant. This raw material is commonly used in pearl mud and colored mud with fluorescent powder. This raw material may cause symptoms such as skin allergies, redness, swelling, and itching in children.

As for why barium was detected in the sample, Tian Yong, a chemical testing engineer at Guangdong Provincial Inspection and Quarantine Technology Center, said that there may be two reasons. On the one hand, the selected raw materials are not qualified, such as using dye additives that can increase color, which may contain heavy metals. It is also possible that the production process is not standardized. Some toy manufacturers use instruments with heavy metal materials, or do not control the instruments and production environment properly during the production process, resulting in product pollution.

What are the hazards of exposure to heavy metals?

Tian Yong explained that children have special physiological characteristics and generally have a strong ability to absorb heavy metals, but it is difficult to eliminate them. Heavy metals are prone to accumulate in children's bodies, which may cause muscle toxicity and lead to symptoms such as skeletal and smooth muscle paralysis and paralysis.

Among them, heavy metal barium can alter the permeability of cell membranes, and after enrichment, it may cause potassium to flow from the blood to cells, which can affect cardiovascular health and lead to chronic diseases. Soluble barium in some plastic materials, such as barium carbonate, is harmful to the human body.

If children are exposed to or accidentally consume colored clay products containing barium for a long time, the initial mild symptoms may include nausea, vomiting, etc. Prolonged excessive exposure can cause harm such as illness.

Tian Yong suggests that when choosing colored clay and clay, it is important to check whether the product has information such as manufacturer and production date, and avoid selecting "three no" products. At the same time, it is best to open the colored clay and clay products and smell them. If there is a particularly strong pungent odor and fragrance, allergenic aromatic agents may be added. Children should be careful not to eat by mistake and wash their hands after playing.

In addition, as colored clay is made from flour, some toy manufacturers add a large amount of preservatives during the manufacturing process to extend its shelf life. Parents should compare and avoid choosing clay products with a long shelf life when selecting them.

■ Link

Can you distinguish the "mud" squeezed by the child?

At present, there are various types of styling toys on the market. What are the differences?

Rubber clay: It is the predecessor of colored clay, usually made of flour, pigment, and vegetable oil, with a single color and added preservatives. Rubber putty is generally oily and easy to stick to hands. Later on, a new type of rubber putty emerged, mainly made of calcium carbonate and other raw materials, with liquid paraffin as the oily component.

Colored clay: It is mostly made from flour, pigments, edible oil and other raw materials, with a heavy weight and rich and diverse colors. Generally speaking, it has little impact on children's health.

Clay: It is often made by "foaming" raw materials such as resin, pigments, and chemical additives, and is relatively lightweight. The chemical composition in clay poses a significant threat to children's health. It is best to play with children over 5 years old who have discernment ability to avoid accidental ingestion.

Soft clay: It is a type of soil with different colors, which can not only be molded into shapes, but also baked to harden and never deform.