REVIEW & OUTLOOK
The Truth About Thimerosal
Democrats and trial lawyers play politics with vaccine liability.
Was it nefarious Dick Armey? Dastardly Senator and Dr. Bill Frist? Or maybe a phantom pediatrician, hired by Eli Lilly to haunt the halls of Congress? From the press coverage, you'd think there's no greater question than who put the now-famous thimerosal rider into the Homeland Security Bill.
Washington has been so busy playing political "Where's Waldo?" that no one has actually bothered to explain the merits. We're happy to fill this void with the facts, especially because they show that protecting thimerosal from runaway legal liability is the right thing to do as a matter of public health. Far from ducking behind Capitol pillars, Republicans should be trumpeting their support.
The story of thimerosal begins in the 1930s, when it was introduced into vaccines to prevent infections from fungi and bacteria. The preservative, an organic mercury compound, was so safe and uncontroversial that nobody even noticed it for 60 years.
Then in 1997, as part of the FDA Modernization Act, Congress required the agency to do an inventory of mercury in all of its licensed drugs and vaccines. By 1999, researchers realized that kids were getting more shots these days, and that the thimerosal combined from all the vaccinations could, theoretically, slightly exceed an EPA mercury guideline. The findings were manna to the small but vocal anti-vaccination lobby that has spent years falsely claiming vaccines cause everything from multiple sclerosis to cancer. They soon claimed that thimerosal caused autism.
In retrospect, the researchers we've talked to agree it was the EPA standard that was the problem. The agency had based its number on a study of pregnant women whose ingestion of significant and sustained amounts of methyl mercury had led to children who later scored slightly lower on neurological and cognitive tests (nothing near autism). The EPA estimated the lowest possible amount a mother could have ingested to be associated with a disorder and then, to be ridiculously safe, divided that by 10. The agency's standard is below that of even the hyper-cautious Food and Drug Administration.
There's little evidence vaccines exceed even that extremely low level. Just last week a University of Rochester study published in Lancet looked at 61 infants--40 receiving vaccines containing thimerosal, and 21 receiving thimerosal-free vaccines. Most children had blood mercury levels of 1 or 2 nanograms per milliliter; the highest level, found in one child, was 4.11 nanograms per milliliter.
By comparison, the EPA standard is 5.9 nanograms per milliliter. The study also found that children excrete ethyl mercury more quickly than expected, so that it doesn't build up from one vaccination to the next. "A mom who eats a tuna fish sandwich probably passes along more mercury during breast-feeding than a kid gets in a vaccination," says Michael Pichichero, the study's lead investigator.
Most important, no scientific study has ever found a link between vaccines and autism, despite years of detailed research into the safety of vaccines. Even the World Health Organization continues to endorse the use of the preservative.
Sadly, the real losers of this wild goose chase are parents of autistic children, who've seen anti-vaccinators use their cause to divert time and resources away from legitimate research into the disorder.
U.S. public health agencies knew most of this in 1999. But they worried that anti-vaccine groups would use the FDA information to scare parents away from immunizations. So they hastily recommended that manufacturers immediately remove the preservative--a huge mistake.
"We took it out precipitously, which made it look like thimerosal is harmful--when there is no evidence it is. I think we hurt the public trust," said Paul Offit, who sits on the Advisory Committee on Immunization Practices and is chief of infectious diseases at the Children's Hospital of Philadelphia.
The recommendation brought unwarranted fear, vaccine shortages, and . . . tort lawyers. Usually, parents of the rare child injured by a vaccine must go through the Vaccine Injury Compensation Program before they can sue in regular courts. Set up by Congress in 1986 after lawsuits all but bankrupted vaccine makers, VICP ensures that victims get compensated quickly for genuine wrongs.
But the tort lawyers hate that VICP cuts out their giant fees, and they saw an opening in thimerosal. They've exploited every loophole to keep frivolous thimerosal cases out of VICP, and have instead filed hundreds of lawsuits against vaccine makers and Eli Lilly (which stopped making thimerosal 10 years ago). The four vaccine makers left are today stuck devoting their funds not to research into new, life-saving vaccines, but to paying legal bills.
These, readers, are the facts behind the thimerosal rider that is supposed to be so scandalous. All the legislation does is require that parents first go through VICP, as with any vaccine claim. They can sue later in other courts, if they choose (and assuming a statute of limitations problem is fixed). The vaccine court is much better positioned than other courts to decide on the merits of thimerosal cases. And it has the added social benefit of protecting vaccine research and production at a time when we need both to defend against bioterror.
None of this makes trial lawyers rich, though, and so they asked Senate Democrats, led by Joe Lieberman, to strip the rider away. They lost, but they did such a good media job that new Majority Leader Trent Lott has promised modifications to protect nervous Republicans who clearly haven't bothered to understand the issue.
We suggest they talk to Dr. Frist, who could supply a nerve transplant. If Republicans can't explain to parents that thimerosal is about supplying safe vaccines to their children, they don't deserve the majority.
