However, this is NOT proof that the two are related. It could just as easily be something about the lifestyle of the test participants lead to both increased BPA concentrations and higher heart risks.
Neither I nor the authors claimed that this analysis proves that BPA
caused the increased risk of heart disease. By definition, this particular data set (NHANES) cannot answer that question so this particular objection is moot in this case.
There have been many interesting "findings" over the years that generated a lot of buzz. However, in many cases, no one has been able to reproduce those results. The fact that these researchers have been able to find the same result in two different sets of data
a priori significantly reduces the chance that this association between BPA and heart disease is just coincidence. They also control for other likely risk factors in their analysis, thus attempting to remove the effects of those other risk factors that might be associated with both BPA and heart disease. And even after doing so, the association persists which seems to strongly imply that there is something going on here, although, yes, there is the possibility that it isn't actually the BPA causing the increased risk.
Reproducibility is just one step on the long road to gathering enough scientific consensus to support a new understanding of some process. As I mentioned, we're still just in the beginning phase of really starting to understand what BPA does or doesn't do using human data.
The fact that they refer to the molecule in question as "endocrine disruptor" suggests that they are already biased...
It is already accepted in the literature that BPA is among a class of biologically active chemicals called "endocrine disruptors". I have read negative studies that also refer to BPA as endocrine disruptors, so I don't consider it a sign of bias.