Before you buy a spot-fading whitening cream, take the «国妆特字» number on the package and check it on the National Medical Products Administration website. Do not use a spot-fading cream sold by a WeChat reseller, or one the beauty salon mixed itself

A spot-fading whitening cream has to be registered with the National Medical Products Administration and get a «国妆特字» number before it can be sold. Spot checks have found spot-fading creams with mercury thousands of times over the limit. The package printed a «国妆特字» number, but the factory named on it had not made that batch. Mercury taken into the body from the face can harm the kidneys. Stopping the cream, plus treatment, gets most people better, but the treatment takes several months to 2 years.

Cost

No money. Checking a number takes a few minutes. The hard part is not buying the ones that acquaintances and WeChat resellers (微商 — people selling through private chats) push the hardest.

Benefit

Article 16 of the Regulations on the Supervision and Administration of Cosmetics lists spot-fading and whitening cosmetics as special cosmetics. Article 17 says that special cosmetics may be produced or imported only after registration with the drug supervision department of the State Council. Article 36 requires the label to carry the special-cosmetics registration certificate number. Article 20 requires the registration information to be made public, so the number can be looked up on the National Medical Products Administration website. Article 62 of the Measures for the Administration of Cosmetic Registration and Filing says that a domestic number is «国妆特字» plus the year and a serial number, and an imported number is «国妆特进字». National Medical Products Administration Announcement No. 14 of 2026 published 2 batches of spot-fading cream, in which mercury was found at 4938 mg/kg (milligrams per kilogram) and 9281 mg/kg. The limit listed in the annex to the announcement is not more than 1 mg/kg. These 2 batches were thousands of times over that limit. They were bought at 2 small cosmetics shops, in Sichuan and in Anhui. The package printed a «国妆特字» number. The factory named on it objected. After review, the Guangdong medical products administration found that this enterprise had not produced that batch. A review brought together 30 cases reported in journals, all of them nephrotic syndrome after using a mercury-containing whitening cream, which means a large amount of protein leaking into the urine. All 30 were Asian women, mostly aged 18 to 52. From starting use to falling ill was 1 to 60 months, and half were within 5 months. Most kidney biopsies were minimal change disease (67%) or membranous nephropathy (23%). These are 2 diseases of the glomeruli, the kidney's filters. Very few got better on their own within a month and a half after stopping. In the cases with a record, those who used a mercury-removing drug took 1 to 9 months for the urine protein to turn negative, with a median of 2 months. All 3 who did not use a mercury-removing drug took more than 12 months. A hospital in Beijing admitted 288 people with mercury poisoning from 2014 to 2019. 84 of them (29.27%) were related to cosmetics. The main source of poisoning among women was cosmetics. Of the 18 patients with nephrotic syndrome who were followed, 15 had urine protein and albumin back to normal after an average of 22.67 months. The mercury in these 18 people did not all come from cosmetics.

Notes

Those 2 batches show that a number can be misused too. When you check the number, see whether the product name, the factory, and the package match what comes up. It is better to buy from the brand's official shop or a regular store. Article 42 of the regulations says that a beauty salon using cosmetics on a customer must follow the rules for a cosmetic operator. Item 5 of Article 60 prohibits an operator from compounding cosmetics on their own. A "salon-line spot-fading cream" that the salon mixes itself is illegal. If you have already used a spot-fading cream of unknown origin for a long time, stop, take the product to a hospital, and check urine mercury and urine protein. In that review, 6 people had normal blood mercury, and all 24 whose urine mercury was checked were above the normal upper limit. The cases were reported case by case, so you cannot calculate what share of people who use a mercury cream will harm their kidneys, and the grade is B for that reason. The benefit magnitude is set at medium from the consequences: nephrotic syndrome can mostly be treated, but treatment takes several months to 2 years.

Sources · 5

1. 国务院 (2020). 化妆品监督管理条例（国务院令第 727 号，第十六条、第十七条、第二十条、第三十六条、第四十二条、第六十条）. gov.cn/zhengce/zhengceku/2020-06/29/content_5…
2. 国家市场监督管理总局 (2021). 化妆品注册备案管理办法（总局令第 35 号，第六十二条）. gov.cn/zhengce/zhengceku/2021-01/12/content_5…
3. 国家药品监督管理局 (2026). 国家药监局关于25批次化妆品检出禁用原料的通告（2026年第14号）及附件. nmpa.gov.cn/xxgk/ggtg/hzhpggtg/hzhpchjgg/hzhp…
4. Chan TYK, Chan APL, Tang HL (2020). Nephrotic syndrome caused by exposures to skin-lightening cosmetic products containing inorganic mercury. Clin Toxicol. doi.org/10.1080/15563650.2019.1639724
5. Yawei S et al. (2021). Epidemiology, clinical presentation, treatment, and follow-up of chronic mercury poisoning in China: a retrospective analysis. BMC Pharmacol Toxicol. doi.org/10.1186/s40360-021-00493-y