Moderna vaccine ingredient falsely targeted as unsafe

CLAIM: SM-102 is an ingredient in the Moderna vaccine that is not safe for humans or veterinary use.

AP’S ASSESSMENT: False. Social media posts suggesting the vaccine is unsafe are comparing two different formulations of SM-102. In one, the lipid is used to coat messenger RNA in Moderna’s vaccine so it can be delivered to cells. In the other, it is preserved in chloroform. The SM-102 used in the vaccine does not contain chloroform, which is toxic.

THE FACTS: As millions of Americans receive COVID-19 vaccines, posts online are falsely claiming that an ingredient listed in the Moderna vaccine is unsafe for humans and animals.

In an effort to prove that point, one Instagram user posted a video that compares the ingredient list for the Moderna vaccine with one used on a chemical solution made by the Michigan biotech company, Cayman Chemical. They both list SM-102 as an ingredient, but the Cayman product comes with a warning that it is to be used for research purposes only and contains chloroform.

“It’s unbelievable how many people are just following this blindly, and not doing active research to find out what they are putting into their, and now their children’s body,” the caption on the video reads.

But social media users sharing the video fail to tell the whole story. The Moderna vaccine does not contain chloroform but it does use SM-102, which is a part of the lipid used to deliver the genetic code, or mRNA of the spike protein that coats the coronavirus, into our cells.

The posts ignore information on the Cayman Chemical that lists chloroform as a “dangerous component” on the product’s safety data sheet and lists SM-102 separately under “other ingredients.”

Following the misinformation, Cayman Chemical released a statement reaffirming that the product being mentioned online is made up of 90% chloroform, a common solvent, and 10% SM-102. It is intended for research purposes only. The company has a separate division for products for human and veterinary use.

“While it is a common solvent, chloroform has several known serious hazards,” the company said in a news release. “Neither the National Institute for Occupational Safety and Health (NIOSH), Registry of Toxic Effects of Chemical Substances (RTECS), or the European Chemicals Agency (ECHA) Classification and Labelling Inventory list any hazards associated with SM-102.

Chloroform is used as a stabilizing medium to transport the lipid, said Dr. Nicholas Davidson, a physician and lipid biologist.

“They are certainly not being injected along with chloroform,” Davidson said of the vaccines.

Experts say there is no need to be concerned about SM-102 being used in the vaccines. The amount of lipid used in the vaccine is very small, said Lisa Morici, an associate professor in the Department of Microbiology and Immunology at Tulane University School of Medicine, in an email.

“Our own cell membranes are composed of lipids,” she said.

Representatives for Moderna could not immediately be reached for comment.


This is part of The Associated Press’ ongoing effort to fact-check misinformation that is shared widely online, including work with Facebook to identify and reduce the circulation of false stories on the platform.

Here’s more information on Facebook’s fact-checking program: