Thursday, March 05, 2015

The "Reader's Digest" version of my recent posts on estrogenic activity arising from BPA-free plastics

The last 3 posts (1, 2 and 3) have gone into quite a bit of detail and at length of the research results of George Bittner and his claims that many BPA-free plastics show estrogenic activity (EA). Here is a short summary of the main points. There are also hundreds of other detailed criticisms of the research, (only some of which I discussed in the previous posts) that further raise doubts about the validity of the conclusions reached by the researchers.

  • Almost the entirety of the claims are based on samples that have been rapidly "stressed" in someway to "simulate" stresses that would naturally occur to the plastic over longer periods of time during normal use.
  • Unfortunately, there is no effort made to understand if the aging that occurred in the rapidly-stressed plastics resembled in anyway the aging that would occur in naturally-stressed plastics.
  • Verifying that there is no aging difference between the rapidly-stressed and the naturally-stressed samples is critical since at no point are the specific EA chemicals identified.
  • This means we do not know if the EA chemicals are artificially-introduced artefacts from the extreme stress conditions or not.
  • This means that we cannot accurately make statements that BPA-free plastics, when used in a normal manner, will also show EA.

That's enough talk about estrogenic activity in plastics for a while.

Previous Years

March 5, 2014 - Mother Jones Tries to Raise the Dead with a "New" Expose of an Old Issue

March 5, 2012 - Here come the Patent Trolls

March 5, 2010 - Reductio ad absurdum

March 5, 2009 - Some hints on the Rheology of Ketchup

March 5, 2007 - Information just wants to be free

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