It is incorrect to use silver to test whether cosmetics contain lead.
The chemical element used to detect silver is mainly sulfur, which is an element that exists in nature and is contained in many products. Therefore, this detection method cannot indicate that the product contains lead and mercury.
The country has very strict requirements on the chemical content in cosmetics. For example, although arsenic, mercury and other substances can be detected in some cosmetics, the content required by national standards is very low. In addition, whitening and freckle removal products are special cosmetics. National standards not only have strict requirements on product formulas, but also the processing technology needs to be inspected.
Extended information:
In this regard, the reporter consulted Luo Mengqi, a doctoral candidate at the Institute of Metal Research, Chinese Academy of Sciences. Luo Mengqi said that blackening of silverware cannot be used as a criterion for testing whether it contains heavy metals or toxic substances.
“In the past, silverware was used to detect whether it contained arsenic, mainly for the arsenic sulfide in arsenic.” Luo Mengqi said: “Silver will generate black silver sulfide when it encounters sulfide, but sulfur has a bactericidal effect. It can be added."
Dr. Luo Mengqi refuted this statement. "If hydrocarbons are produced during combustion, the residue after combustion will be black. There are many possibilities for the formation of hydrocarbons, and it is impossible to determine whether it contains a specific substance."
In the same way, the absence of black residue only means that it does not contain or contains a small amount of hydrocarbons, but it does not mean that its ingredients are 100% safe.
Reference material: People's Daily Online - Can silverware detect heavy metals? Don’t be fooled, these tips are unreliable