For years, researchers have been studying a possible link between vaccines that contain a mercury based preservative and mental disorders such as autism. Some recent studies have refuted that claim, but some say there still isn't clear evidence in either direction.

While the medical community continues to study the issue, eight states have already taken action. Iowa, Delaware, Hawaii, California, New York, Illinois, Missouri and Washington have either banned or reduced the amount of mercury in childhood vaccinations. Here in South Dakota, vaccines with almost five times the FDA's recommended limit are still being used. One South Dakota law maker is trying to change that.

Currently in South Dakota, flu shots are free. But representative Dan Ahlers says with the amount of mercury they hold, they could come with a cost you don't know about.

While research is still unclear about mercury preservatives in vaccines, it's clear mercury itself can cause serious problems.  That's why one lawmaker doesn't want to take any chances.

"You can get cerebal paulsi, mental retardation, seizures, and it can cause deafness. I mean there's a whole host of very serious disorders," said Representative Dan Ahlers.

Representative Dan Ahlers has introduced a bill that if passed, would bring the mercury levels in vaccinations for children and pregnant women down to the FDA recommended level.

The FDA recommendation for mercury in vaccinations is .5 micrograms per.5 milliliter dose. Alhers says the state's influenza vaccination is five times that.

"Every group says more studies need to be done. So if we're in doubt about the effects of mercury in these vaccinations, then we need to keep it out," stated Ahlers.

Despite his conviction, Ahlers believes the bill wont the pass in the legislature because of the cost. Mercury reduced shots would cost $3.10 more a piece.

For some parents, a vaccine with less mercury is worth the extra money, and even worth driving to another state. Julie Baumberger, a mother of three, is one of those parents. She says she wouldn't think twice about driving to Iowa, where they openly offer reduced mercury vaccinations.

"I'd rather spend the extra gas money, spend whatever it's going to cost to see a doctor down there and give them the shot that's mercury reduced then knowingly put it in their system," said Julie Baumberger, a mother of three.  

Alhers says because of the high mercury content in vaccinations, some parents are choosing not to get their kid's vaccination until they reach Kindergarten. That leaves the potential for serious diseases to be spread in daycare.