Are seriously ill babies in the NICU at risk for developing even more health problems because of all the plastic they're exposed to in incubators, breathing tubes, and the other equipment?
There's been much speculation about one ingredient in plastics, phthalates. One worry is that the chemical could act like a hormone and ultimately a carcinogen. There's some evidence rats given very large doses develop hormonal abnormalities. Some say scientific evidence does not warrant the clamor and ban on phthalates (see the other NPR story "Public Concern, Not Science, Prompts Plastics Ban").
But how could we study the issue in humans? Which population should we study?
What about babies in the NICU?
A group of researchers speculated that if phthlates were dangerous, we might be more likely to see evidence of their risk in the more vulnerable populations, like premature and sick babies in the NICU, who are not only in poor health at a critical developmental period but also exposed to more phthalates early on due to their hospital care.
I bring up this issue not only because phthalates have been a hot topic in the parenting loop, but also because a recent NPR story (Surrounded By Plastic, NICU Infants Tested For Risk) gets at some of the problems and choices researchers encounter when they want to study something and also how and why they choose certain study populations.
Why not focus on a healthy population, kids who weren't in the NICU? Well, for one thing, they might not be effected by the substance. Or the effects would be so tiny they'd not turn out significant. A good study would include these kids as a control group. But I can imagine a large study using ONLY this population then concluding the possible perilous plastic wasn't dangerous. Then we'd have to wonder about the more at risk kids.
BTW, the researchers didn't find any harmful effects (like premature sexual development or abnormal hormonal levels) in the NICU children they'd followed. Of course the sample was limited to only 18 kids - way too small a sample to find any minor effects.