Robert F. Kennedy Jr., a Secretary of Health who wants to bend science

U.S. Surgeon General and vaccine skeptic Robert F. Kennedy Jr. has called for the retraction of a Danish study that found no link between aluminum in vaccines and certain chronic childhood diseases—an unusual move for a senior U.S. official. Aluminum has been used for nearly a century to enhance the immune system's response to certain vaccines. But some argue the adjuvant is linked to an increase in childhood-onset disorders, such as autism.

It's rare for public health officials in positions like Kennedy's to request that studies be retracted, says Ivan Oransky, an academic publishing specialist and co-founder of the media organization Retraction Watch. With this request, "Secretary Kennedy has demonstrated that he wants the scientific literature to bend to his will," he says.

The study in question, published in July in the Annals of Internal Medicine, is one of the most comprehensive of its kind: it covers 1.2 million children born over a period of more than twenty years in Denmark. The authors conclude that no significant risk of autoimmune diseases, allergies, or neurodevelopmental disorders is associated with the experiment.