Plastics Plus Prenatal Equals Autism: The Arithmetic of Autism with the New York Times

The Worst Science Writer of 2009, Nicholas Kristof, is at it again. This time blaming environmental toxins for that other sure to scare parenting topic, autism - in his New York Times column read by millions (Do Toxins Cause Autism? ).

How do you scare parents silly? Mention toxins, prenatal brain development and autism together.

The research linking prenatal exposure to autism? None other than the pregnant pee study I've already debunked. (Pregnancy Pee Linked to Kid's Bad Behavior: Phthalates, ADHD, Conduct Disorder, OH MY!).

Why the autism epidemic?
One uncertainty is to what extent the reported increases in autism simply reflect a more common diagnosis of what might previously have been called mental retardation. There are genetic components to autism (identical twins are more likely to share autism than fraternal twins), but genetics explains only about one-quarter of autism cases.
Of course the remaining three-fourths must be attributed to environmental toxins working on developing minds.  It seems he's talking about studies of heritability - which is a highly complicated technical term which gets misinterpreted all the time and involves the genetic portion of autism in populations not individuals.  I have no idea what Kristof's one-quarter means.

Then the confusing mental retardation issue.

I just don't understand his reasoning here and I'm accustomed to reading scientific mumbo jumbo. Does he mean one reason we see more autism is that kids who used to be called mentally retarded are now diagnosed as autistic?  Studies have looked into it this and many have concluded children who had autistic symptoms coupled with mental retardation are more likely to just get the autistic label than the MR label these days.  But it's not like a lot of mental health professionals are largely attributing the rise to this change.   

So Kristof assumes that if simple mental retardation re-classification and genetics can't account for the rise, then the rest must be environmental toxins?

Somehow he talks about mental retardation but misses the other significant explanations.....

Like the expanded Autistic Spectrum, namely the addition of Asperger's Syndrome and Pervasive Developmental Disorder-Not Otherwise Specified.  Not to mention increased public and professional awareness of autism?

It's ridiculous to address the increase of autism diagnoses without mentioning the broader definitions of autism.  

Or if we're talking correlational evidence, as in potential "causes", the links to paternal and now maternal age.  

There are no doubt a variety of causes, including environmental triggers.  Do they have to be chemicals or toxins we worry about?  No, it could also be other environmental factors.  When researchers and science-types say "environmental" they're talking about anything that isn't genetic.  Meaning, everything else, not just scary-sounding substances.  It includes vitamins, minerals, diet, sunshine, exercise, watching television or whatever doesn't involve genes.  So environment covers a lot.  Could phthalates trigger autism?  Yes, but we don't have good evidence, not yet. 

To his credit, Kristof acknowledges writing about scientific evidence is not easy for non-scientists.
Frankly, these are difficult issues for journalists to write about. Evidence is technical, fragmentary and conflicting, and there’s a danger of sensationalizing risks. Publicity about fears that vaccinations cause autism — a theory that has now been discredited — perhaps had the catastrophic consequence of lowering vaccination rates in America.
"Perhaps" lower vaccination rates? - no, DID lower vaccination rates.

"Fragmentary?"  Not a technical term bandied about in research circles, maybe he refers to the slow, gradual accumulation of evidence across studies and different samples and methodologies?  I have no idea.

But I interrupt....his argument for becoming a pseudo scientific authority.
On the other hand, in the case of great health dangers of modern times — mercury, lead, tobacco, asbestos — journalists were too slow to blow the whistle. In public health, we in the press have more often been lap dogs than watchdogs.
So I agree Mr. Kristof.  I love a good conspiracy theory almost as much as the movie. By the way, I still love Russell Crowe in The Insider giving it to the ciggie makers.  But you of all peeps should realize these times they been a'changing.  We got non-stop 24/7 access to information - of all types and quality.  Including so many misinterpreted and just plain crappy studies from so many non-scientists.  It's getting much harder to distinguish real dangers from false alarms. 

FYI: I often enjoy Mr. Kristof's column when he sticks to his area of expertise. If he isn't careful he's gonna be Worst Science Writer of 2010.


TheRextras said...

Give 'em heck, Polly!


Polly Palumbo, Ph.D. said...

Thanks, Barbara! You know, one of the things that bothers me about Mr. Kristof branching off into phthalates and other toxins - now I'm starting to wonder if he's an expert on his usual columns that I've enjoyed over the years. He's losing some of his cred with me. And it's too bad because he seems so earnest, likeable.

TheRextras said...

And then there's this reasonable sounding MD getting excoriated by commenters:

I have good awareness, but know I'm just on the periphery of all that is published on this topic.

Sincerely, the more competent voices the better!