Yet they constitute a huge national health burden, and suspicions are growing that one culprit may be chemicals in the environment. An article in a forthcoming issue of a peer-reviewed medical journal, Current Opinion in Pediatrics, just posted online, makes this explicit.

The article cites “historically important, proof-of-concept studies that specifically link autism to environmental exposures experienced prenatally.” It adds that the “likelihood is high” that many chemicals “have potential to cause injury to the developing brain and to produce neurodevelopmental disorders.”

The author is not a granola-munching crank but Dr. Philip J. Landrigan, professor of pediatrics at the Mount Sinai School of Medicine in New York and chairman of the school’s department of preventive medicine. While his article is full of cautionary language, Dr. Landrigan told me that he is increasingly confident that autism and other ailments are, in part, the result of the impact of environmental chemicals on the brain as it is being formed.

“The crux of this is brain development,” he said. “If babies are exposed in the womb or shortly after birth to chemicals that interfere with brain development, the consequences last a lifetime...”

Boston.com, February 27, Joanna Weiss: Seeking common ground in the autism-vaccine debate

"...American Academy of Pediatrics urges doctors to work with skeptical patients, but Fisher says that isn’t always easy. Doctors worry that children will get sick or spread diseases to other patients. They don’t want their good intentions to be questioned. And so parents who raise doubts can find themselves treated like nuisances or enemies of science. Some of them walk away.

I’m not arguing against vaccinations, but I do think doctors need to give parents more credit for seeking information, and approaching medicine with some degree of skepticism. History is filled with stories of well-meaning doctors prescribing medicines that turned out to be harmful. In very rare cases, vaccines can cause damage. And while vaccines have been made significantly safer over the years, it’s not irrational to think that, with more study, they could become safer still.

Again, that’s not to say that parents should ignore the threat of infectious disease - anecdotes about children suffering from whooping cough are enough to give anyone pause. But something needs to change in the doctor-patient relationship, too, which is why some pediatricians are preaching compromise.

Perhaps the most famous of them is Dr. Bob Sears, the son of attachment-parenting guru William Sears. In “The Vaccine Book,’’ Sears, the son, promotes an alternative schedule he says urges vaccine coverage for some of the most common and life-threatening diseases for infants - such as meningitis and whooping cough - while giving parents permission to delay other shots..."

The New York Times, February 22, Gardiner Harris: A Face-Off on the Safety of a Drug for Diabetes

"Three years ago, Dr. Steven E. Nissen, a cardiologist at the Cleveland Clinic, conducted a landmark study that suggested that the best-selling diabetes drug Avandia raised the risk of heart attacks. The study led to a Congressional inquiry, stringent safety warnings, a sharp drop in the drug’s sales and a plunge in the share price of GlaxoSmithKline, Avandia’s maker.

The battle between Dr. Nissen and GlaxoSmithKline was waged from afar in news releases and published papers. But on May 10, 2007, 11 days before Dr. Nissen’s study was published in The New England Journal of Medicine, he and four company executives met face to face in a private meeting whose details have not been disclosed until now.

Fearing he would face pressure and criticism from executives, Dr. Nissen secretly recorded the meeting — which is legal in Ohio as long as one party to the conversation is aware of the taping. On a recent day in his sunny office at the Cleveland Clinic, Dr. Nissen shared the contents of the recording with The Times.

What was said at the 2007 meeting raises questions about science and ethics that have suddenly become keenly relevant. A Congressional investigation released Saturday concluded that GlaxoSmithKline had threatened scientists who tried to point out Avandia’s risks, and internal memorandums from the Food and Drug Administration show that some government health officials want Avandia withdrawn. The drug is still being taken by hundreds of thousands of patients, and sales last year were $1.19 billion..."