We all know to avoid clear plastic water bottles because they leach endocrine-disruptor BPA into the water, but what about the alternatives?
A new study by the University of Cincinnati College of Medicine was done to find out whether or not water bottles claiming to be “BPA-free” really are. The researchers used old (but unused) polycarbonate and resin-lined aluminum bottles that they had put in storage several years earlier, along with new BPA-free “Tritan” plastic bottles (by Nalgene), stainless steel bottles (by Sigg) and new “EcoCare” resin-lined aluminum bottles (by Sigg). They also purchased some new aluminum water bottles.
Room-temperature water was storied in three bottles of each type for five days and another set of bottles was filled with boiling water (and then let the water cool to room temperature over the next day).
Levels of BPA were below the limit of detection for the new Sigg and Nalgene bottles.
The old polycarbonate bottles leached 0.17 to 0.3 nanograms of BPA per milliliter of water during the room temperature tests. The old aluminum bottles with an epoxy-resin liner leached 0.59 to 0.14 nanograms per milliliter.
Brand-new epoxy-resin-lined aluminum water bottles leached up to six times more BPA than the worst-leaching polycarbonate bottle and more than 10 times as much BPA as the polycarbonate-plastic bottle that had leached the least.
Hot water quadrupled BPA leaching over what occurred when water had been kept at or below room temperature.
The bottles that had been sold as BPA-free in fact did not leach the steroid-hormone-mimicking pollutant.
