Pregnancy Pee Linked to Kid's Bad Behavior: Phthalates, ADHD, Conduct Disorder, OH MY!

Pregnant Mom Alert #523: Clear out your cosmetics. Ditch the deodorant. Trash your toiletries. Contact your Congressperson.

Phthalates, again! In your beauty regime.  Seems they harm your unborn baby's developing brain eventually turning them into aggressive, surly kids, maybe even criminals. So says a Mount Sinai study published online in this month's Environmental Health Perspectives, sure to alarm even the more placid of pregnant folk.
After measuring phthalates in the urine of pregnant women in their third-trimester, researchers followed up with 188 moms to ask them about their children's behavior. Women who had the highest levels of phthalates reported their kid (aged 4 to 9) had more problems with poor behavior, aggression, and attention - mirroring symptoms of ADHD and Conduct Disorder.

Which phthalates? The ones in some personal products like cosmetics, nail polish, shampoo, and lotion. The other types of phthalates tested in the study didn't produce any significant results.  Like the ones in soft plastics and toys. 

Good study?

An okay study with solid methodology for the most part.  It's a large sample. We have a physiological marker.  But I wouldn't call it "very well done" as did Dr. Philip Landrigan,  a pediatrician at Mt. Sinai and the Director of the Children's Environmental Health Center (ahem, scene of the study). 

But here're the weaker points.

First off, it's correlational - we don't know if phthalates caused the poorer conduct. It's not an experiment. There may be other reasons for the results. For instance, other characteristics of women who like lots of toiletries that might lead to the conduct issues. Maybe personality? Some parenting approach, like discipline. I don't know - but neither do our investigators. And frankly, who primps in the last months blown up like that? I wore my husband's t-shirts and was lucky to fix a neat pony tail.

Then there's the time frame, the years between the preggers pee and the bad behavior. So there could be numerous other factors involved. Be curious when you have a long time span. But, you ask, doesn't that mean the phthalates are really powerful to have such lasting effects? Well, it would have been better to get reports at even earlier ages too.

Then there's the kid's behavior. According to their mothers. Are they always accurate? No idea. It would have been better to have corroboration from a teacher, another professional. The better studies do this. Like I said earlier, moms who lay on the toiletries  could be biased too.  Most of the women were from low-income households, so not a representative group.

Small issue, but the results don't involve ADHD and Conduct Disorder. It's unclear whether the behavioral reports could have given the researchers an idea if the bad behavior reached the levels of these diagnoses. Obviously the moms couldn't diagnosis their own kids. A better study would have used diagnoses. Maybe look at kids diagnosed versus those not diagnosed. Used medical records in conjunction with mother's reports. And hey, why not teachers too.

Another small quibble. Moms got phthalates in urine, that is, leaving her body. Not clear how phthalates actually affect fetuses. Some think maybe through developing thyroid. But we just don't have this evidence. Maybe soon. But not yet so we really can't conclude the phthalates changed the tiny brains.

None of this prevent the lead author, Stephanie Engel from concluding a causal link in an interview:

“Clearly environmental toxicants play a role in child neurodevelopment..."

Clearly she might be right - but not about this study. 

So I'm not calling my Congressman yet.  At least not about  phthalates.  Now, where's that nail polish I've owned since 1997?

Thanks to the reader who brought the study to my attention! Loved the opportunity to show off a hot pregnant chick...

Engel, S., Miodovnik, A., Canfield, R., Zhu, C., Silva, M., Calafat, A., & Wolff, M. (2010). Prenatal Phthalate Exposure is Associated with Childhood Behavior and Executive Functioning Environmental Health Perspectives DOI: 10.1289/ehp.0901470


momof3 said...

I would have worried if I'd read about the study without your explanation. I have enough to be worried about, no need for extra.

JGK said...

Why don't we hear this more?