JEFFERSON CITY, Mo. -- A bill that would restrict mercury levels in vaccines was sent to the governor on Wednesday, despite House changes that almost derailed the measure in the Senate.

As of April 1, 2007, the bill would bar immunizations containing more than one microgram of mercury per one-half milliliter dose of vaccine for children under age 3 and pregnant women. Mercury is sometimes used as a preservative in vaccines.

Some parents and advocates blame mercury for a nationwide rise in autism, hyperactivity and attention deficit disorder.

Pending the governor's signature, Missouri would become the third state, along with California and Iowa, to restrict a preservative called thimerosal -- which is 50 percent mercury by weight.

As originally passed by the Senate, the bill was limited to mercury restrictions. However, the House expanded the measure into an omnibus health-care bill.

Two changes that would undo some of the cuts to Medicaid eligibility the legislature enacted earlier this year prompted state Sen. Jason Crowell, a co-sponsor of the mercury bill, to oppose the final version. The Senate sent the measure to Gov. Matt Blunt on 29-2 vote.

"I greatly support the elimination of mercury in vaccines and have done as much as anyone and more than most to move that bill forward," said Crowell, R-Cape Girardeau. "But I was forced to make an up-or-down vote, and my conclusion was the bad outweighed the good. It was a tough call. Given that the legislative session ends Friday, the bill's primary sponsor, state Sen. Norma Champion, opted to accept the House version rather than forcing negotiations to remove some of the extra provisions and risk losing the bill."

"We should at least send a message that Missouri is concerned about mercury and immunizations," said Champion, R-Springfield.

State Sen. John Loudon, R-Ballwin, threatened to block a final vote because the House stripped tougher regulations of vaccines that he had sought.

"This bill captures the lowest amount of people and then provides every conceivable loophole," Loudon said. "It is truly and sincerely of no use."

After the measure was temporarily set aside, Loudon agreed to stand down.

Lujene Clark, a former nurse and parent of an autistic child, lobbied for the measure. The Carthage, Mo., woman said she is thankful that Champion and Crowell introduced the bill, she was "deeply disappointed" that the age restriction was placed at 3 years after pressure from the governor.

She said the "real hero" was Loudon, who said the state would continue to monitor the scientific evidence and revisit the issue in the future.

Other provisions added by the House include those related to newborn screenings, disseminating information regarding the exposure risks of hepatitis C and the issuance of birth and death certificates.

The bill is SB 74.

Staff writer Bob Miller contributed to this report.

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