Wednesday, Jim Carrey and Jenny McCarthy along with other national autism advocacy groups participated in the “Green Our Vaccines” march in Washington, D.C.

According to ABC News, the actors want to make people aware of autism and of the fact that vaccines contain toxins that may have a connection with autism.

McCarthy’s 6-year-old son, Evan, has autism and many of her actions were towards new research for this disorder. She even wrote a book called "Louder Than Words: A Mother's Journey in Healing Autism," which became a best seller. The book described her efforts to make her son overcome his symptoms by medication, therapy and an appropriate diet.

This march promotes toxins-free vaccines and requests children's vaccination schedules to be changed.

Although many parents who have autistic children believe that there’s a link between the children’s vaccines and autism, the Institute of Medicine reported that 19 studies have showed there was no link between those two.

In 2001, thimerosal was removed from the vaccines but autism rates have continued to rise.

According to the organization “Talk About Curing Autism,” almost one in every 150 children in the U.S. has autism.

Doctors fear that, if parents link autism with the vaccines, they will not let children to be vaccinated, causing childhood diseases like measles, mumps and rubella to spread, leading to an outbreak.

McCarthy and Carrey said that they were not against the immunization of the children, adding that there were “too many vaccines, too soon, many of which are toxic,” reported ABC News.