Days before the election, Kennedy posted on social media that a Trump White House would advise all U.S. water systems to remove fluoride from the public water supply, which goes against public health recommendations yet jibes with a large number of people who question the safety of fluoridating water.

President-elect Donald Trump’s pick to lead the Health and Human Services Department is raising concerns in the dental community over his push to rid the country’s public water supply of fluoride.

Fluoride is missing from 43% of Californian faucets, including Bay Area towns of Los Altos, Santa Cruz, Novato and parts of Santa Clara, San Jose and Livermore.