Bisphenol-A
Sep. 16th, 2008 04:43 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
snousleSome recent research concerning the effects of bisphenol-A have caught my attention. This is something potentially very big. I'm not sure the general public has the ability to discriminate between risk exposures that are pretty decisively harmless - like thimerosal in vaccines, or low frequency electromagnetic radiation - and things where the research really does suggest an as-yet unappreciated risk. I'm thinking this is in the latter category.
The trouble with the debates these things generate is that, on any scientific question that is at all controversial, the evidence on both sides will seem quite compelling. A few years back, I spent quite a bit of time reading about the DDT controversy and how it unfolded. As Barbie might say, "Toxicology is Hard!". Just being a little bit selective in your examination of research would lead you to entirely opposite conclusions, because its effects, though pronounced, were spotty and hard to nail down. Once it was recognized that only birds of prey were affected, the situation became much clearer.
The research on bisphenol-A paints a picture of a compound that could be having observable effects in a lot of people at exposures that are common in the US population. It has been correlated with insulin resistance and heart disease. Curiously, it may also be a compound where its effects at low doses are the reverse of the high-dose effect; Science News sadly does not have the graph available on its web site, but this site discusses the general issue of non-monotonic responses with reference to bisphenol-A in particular. This is a theme that is also very relevant to John's work in tracing compounds at very low concentrations, well below the range of the most sensitive chemical tests. Low doses of compounds might be following entirely different metabolic paths from higher ones.
If Wikipedia interests you it's also worth checking out the article on this subject - it's a good case study of the strengths and weaknesses of that site. On the plus side, I appreciate how adherence to the Wiki principles has resulted in what an encyclopedia article should be, a collection of relevant and useful facts without much in the way of interpretation. However, despite this being an extremely useful industrial chemical, the article says relatively little about what it's actually used for, and dwells almost entirely on the one aspect of it that happens to be controversial. This seems less than ideal. The talk page is also very interesting, if you're into the nitty gritty of how these things unfold.
Anyway... I dunno if this is all on the evening news yet but it might be soon.
The trouble with the debates these things generate is that, on any scientific question that is at all controversial, the evidence on both sides will seem quite compelling. A few years back, I spent quite a bit of time reading about the DDT controversy and how it unfolded. As Barbie might say, "Toxicology is Hard!". Just being a little bit selective in your examination of research would lead you to entirely opposite conclusions, because its effects, though pronounced, were spotty and hard to nail down. Once it was recognized that only birds of prey were affected, the situation became much clearer.
The research on bisphenol-A paints a picture of a compound that could be having observable effects in a lot of people at exposures that are common in the US population. It has been correlated with insulin resistance and heart disease. Curiously, it may also be a compound where its effects at low doses are the reverse of the high-dose effect; Science News sadly does not have the graph available on its web site, but this site discusses the general issue of non-monotonic responses with reference to bisphenol-A in particular. This is a theme that is also very relevant to John's work in tracing compounds at very low concentrations, well below the range of the most sensitive chemical tests. Low doses of compounds might be following entirely different metabolic paths from higher ones.
If Wikipedia interests you it's also worth checking out the article on this subject - it's a good case study of the strengths and weaknesses of that site. On the plus side, I appreciate how adherence to the Wiki principles has resulted in what an encyclopedia article should be, a collection of relevant and useful facts without much in the way of interpretation. However, despite this being an extremely useful industrial chemical, the article says relatively little about what it's actually used for, and dwells almost entirely on the one aspect of it that happens to be controversial. This seems less than ideal. The talk page is also very interesting, if you're into the nitty gritty of how these things unfold.
Anyway... I dunno if this is all on the evening news yet but it might be soon.
