The Golden Globe-winning actor slammed Brown on Twitter, calling him a "corporate fascist" who was poisoning children by signing into law the vaccination requirements.
"California Gov says yes to poisoning more children with mercury and aluminum in manditory vaccines," he said. "This corporate fascist must be stopped."
He went on to say the
Carrey, who lives in Los Angeles, said he does not oppose vaccines, but is rather "anti-neurotoxin." He believes vaccines should be free of chemicals and certain compounds, such as mercury and thimerosal.
"All we are saying is, 'Take the neurotoxins out of the vaccines.' Make them toxin free. History will show that that was a reasonable request."
Carrey dated former "The View" cohost
She claimed her son's autism was caused by vaccines. In March 2014, she hosted #JennyAsks on Twitter and was ridiculed for her anti-vaccination views.
Brown signed the law Tuesday, a move that could push opponents of immunization to court.
"The science is clear that vaccines dramatically protect children against a number of infectious and dangerous diseases," Brown said in a statement. "While it's true that no medical intervention is without risk, the evidence shows that immunization powerfully benefits and protects the community."
The stricter regulations come months after a measles outbreak centered on Disneyland sickened 150 people across the West.
Many parents have sought waivers from vaccine requirements due to concerns about the safety of vaccines, which public health officials said helped allow the measles outbreak to spread.
The new law allows exemptions for schoolchildren only when a doctor "believes that circumstances -- in the judgment and sound discretion of the physician -- so warrant," Brown said.
The new law was met with disappointment by opponents, who like Carrey have protested the move, saying it violates the right of parents to make choices about their children's health.
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