tag:blogger.com,1999:blog-6010505890506526002.post6415809746400412475..comments2024-03-29T03:15:16.064-04:00Comments on Just Like Cooking: BPA-Affected Mating? Something's Fishy...See Arr Ohhttp://www.blogger.com/profile/09464185815368499346noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-6010505890506526002.post-25106787185092662632012-07-12T11:38:44.343-04:002012-07-12T11:38:44.343-04:00Bioaccumulation, the concentration up through the ...Bioaccumulation, the concentration up through the food chain you mention, is certainly cause for concern with endocrine disruptors. However, in the present study (14 days long), I doubt there's enough time to prove persistent effects.See Arr Ohhttps://www.blogger.com/profile/09464185815368499346noreply@blogger.comtag:blogger.com,1999:blog-6010505890506526002.post-69371620962522730412012-07-12T11:37:15.840-04:002012-07-12T11:37:15.840-04:00Wow, thanks for that! This might be the most techn...Wow, thanks for that! This might be the most technically replete comment I've ever received...See Arr Ohhttps://www.blogger.com/profile/09464185815368499346noreply@blogger.comtag:blogger.com,1999:blog-6010505890506526002.post-73742342934370714012012-07-12T11:28:26.581-04:002012-07-12T11:28:26.581-04:00As to your first point on dose, you're right t...As to your first point on dose, you're right that the little guys are literally swimming in BPA, but your comparison with a human reference dose isn't quite the right way to get there. A better way is to compare with the fish equivalent called a predicted-no-effect-concentration (PNEC), which in Europe has recently been set at 1.5 micrograms/L (other estimtes are higher). Like a reference dose for humans, the PNEC is a conservative value with safety factors built in. Multi-generation studies on fish indicate no effects at concentrations in the range of 16 micrograms/L (the NOEC), with effects being observed at higher concentrations. So, the 1,280 micrograms/L test concentration is >800 times above the PNEC and 80 times above the NOEC. As you say, they're literally swiminng in BPA, at a level that would be expected to cause effects.<br /><br />On your third point, and more importantly, the median concentration of BPA detected in North American freshwater is 0.081 micrograms/L with 95th %ile at 0.47 micrograms/L (see http://dx.doi.org/10.1021/es900598e). Levels in Europe look to be a bit lower. The test concentration was >15,000 times higher than the median actually in North American freshwater and >2,700 above the 95th %ile.<br /><br />Unfortunately the researchers only tested one very high concentration so difficult to know if their results are of any environmental significance.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6010505890506526002.post-77400184414556299702012-07-12T10:51:49.785-04:002012-07-12T10:51:49.785-04:00Perhaps pertinent to this is the problem with Colo...Perhaps pertinent to this is the problem with Colony Collapse Disorder (CCD), which has nearly wiped out the honey bee in North America.<br /><br />They were blaming it on mites, on diseases, on global warming, even cell phones. (Actually, the cell phones in an odd way were a hint to the actual cause.) The one thing that everyone accepted could not be the cause was pesticide use, because the pesticides in use were harmless to bees.<br /><br />So they thought.<br /><br />The latest research (May 2012) showed that a class of pesticides assumed to be harmless to honey bees actually isn't. While individual bees could survive an accidental application, the pesticide was being collected in pollen and nectar and thereby being stored and concentrated in the hives. There, the pesticide began to have a long term effect. Where the stored pesticides did not outright kill individual bees, it weakened them and left them vulnerable to diseases and parasites, and led to the rapid collapse of many beehives.<br /><br />The cellphone correlation? Most commercial farming operations and bee-keeping is in areas where cellphones are in prevalent use. Wild hives in rural areas away from modern farming systems, were less likely to be exposed to pesticides. Hence, why hives near populated areas (and thereby, cellphones) were more affected than wild hives in isolated areas.W_D_Richardshttps://www.blogger.com/profile/12841283259590535613noreply@blogger.com