Posts falsely claim that COVID-19 vaccines contain arsenic

Other social media users falsely linked COVID-19 vaccines to dementia.

In the past week, an X post cited a study from an anti-vaccine journal to falsely claim that Pfizer’s COVID-19 vaccines contain arsenic, inciting panic in the comments. Another X post shared an article falsely linking mRNA vaccines to neurodegenerative diseases.


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On October 14, an X post from a U.K.-based account claimed that a study found arsenic in all tested batches of Pfizer’s COVID-19 vaccines, with levels exceeding the safe exposure limits for drinking water as set by the Environmental Protection Agency in the U.S. The study was published in the International Journal of Vaccine Theory, Practice, and Research, a U.S.-based, anti-vaccine journal known for spreading false and misleading claims about vaccine safety. The post received approximately 826,000 views, 31,000 likes, 14,000 reposts, and 530 comments as of October 21. Many comments expressed outrage at the study’s results, with some stating that vaccine manufacturers are committing “crimes against humanity.”

On October 10, an X post from a Switzerland-based account shared an article falsely claiming that human cells can misinterpret the mRNA sequence in mRNA COVID-19 vaccines, leading to the production of “molecular waste.” The article alleges that this waste contributes to neurodegenerative diseases like dementia. The post received approximately 107,100 views, 2,100 likes, 1,000 reposts, and 140 comments as of October 21. Many comments suggested, without evidence, that people who have received mRNA COVID-19 will soon die.


Recommendations brought to you by the health communication experts behind Infodemiology.com.

Health messaging recommendations

Each week, the Infodemiology.com team will provide messaging recommendations in response to some of the trending narratives outlined above. These helpful tips can be used when creating content, updating web and FAQ pages, and developing strategy for messaging about health.

In response to concerns about COVID-19 vaccine ingredients and false claims about vaccine side effects, health care providers and public health communicators may explain that metals like arsenic are not present in Pfizer’s COVID-19 vaccines or in COVID-19 vaccines from other manufacturers. Talking points may emphasize that nearly all of the ingredients in COVID-19 vaccines are also ingredients in many foods and that all vaccines are rigorously tested using strict safety standards before they are approved. Additional messaging may explain that COVID-19 vaccines are not linked to neurodegenerative diseases and that severe vaccine side effects are extremely rare. Staying up to date on COVID-19 vaccines is a safe way to prevent severe illness, hospitalization, long-term health complications, and death from COVID-19.