Frogs & Flame Retardants
About ten years ago, frogs were allegedly disappearing all over the world. At the time, the perceived cause focused on “global warming” re-termed “climate change,” and more recently “climate disruption” and “climate chaos.”
Whatever the terminology used, the frogs’ demise was determined to be the harbinger of a worldwide “climate catastrophe” in the making. The “consensus” scientific opinion at the time fingered carbon dioxide (CO2) and the then-widely claimed “global warming” as the cause of the problem.
Attack on the Frogs
But the demise of the frogs turned out to be more arcane. It was not “warming” of any sort but a fungal infection called chytridiomycosis (Batrachochytrium dendrobatidis) which caused the problem. That virus was spread all over the world, even into the most pristine environs of the world’s jungles from the use of virus-infected South African Clawed Frog (Xenopus sp.) samples used in common pregnancy tests.
Indeed, some frog species were close to extinction then, like the Panama Golden Frog (PFG, actually a toad, Atelopus zeteki) and its relatives. These species had never before experienced anything like the B. dendrobatidis and were (biologically) unprepared for its effects, but nature is tough and a few specimens survived, now with more determination and new-found natural defenses against the virus attack.
Low and behold, over the last decade the Panama Golden Frog has miraculously recovered and its numbers are still rebounding. Conservation and breeding efforts in various facilities also helped to keep it alive.
However, there are new dangers lurking for the frogs – so we are told – like flame retardants.
Flame Retardants
Flame retardants are materials that, when added in small amounts to common materials that are otherwise highly flammable and combustible items like clothes and many household items, prevent or subdue the propagation of their burning. For example, many children’s clothes, such as PJ’s, furniture laminates, TV housings and the like all contain some flame retardants (FRs).
For the last few decades, such FRs contained synthetic materials like “brominated biphenyls” (BBs) and similar brominated types of compounds. The bromine atoms in such synthetics were then generally thought to be “non-bio-accumulative.” That means the compounds were thought to have molecular sizes that would prevent their accumulation in the natural food-chain. However, more recent findings appear to show that even these comparatively large molecules can migrate through biological membranes and accumulate in fatty tissues. Frankly, I am still a bit dubious about such claims.
In addition to the suggestion of BBs being bio-accumulative, there are even more critical issues in terms of their (potential) biological significance, namely the potential for them to act as “endocrine disruptors” (EDs).
There was much talk about “feminisation” of male portions of various species, including humans, a dozen years ago or so. However, since then not much new information has appeared. In fact, the great promise to fund major research activities on that front has all but fizzled out.
Endocrine Disruption
Right now, some studies – again – claim the BBs and similar compounds to be such “endocrine disruptors” (EDs). In simple terms, EDs interfere with the normal function of the body’s hormones by “pretending” to be like them. However all data I have seen indicate that such concerns are not realistic.
Both the endocrine effects, as measured by such compounds’ binding activity to the estrogen receptor and their presence in any tissue could – at worst – constitute effects several orders of magnitude below those of other known endocrine-active compounds that are common in the natural system and found in any vegetable.
In other words, the claimed endocrine disruptor effect is just another hypothesis which, given time, I would expect to fail providing even a plausible, never mind satisfactory explanation, for the observations made in nature. A mere decade ago, everyone appeared to be utterly convinced that “global warming” was to be blamed for any and all problems including the frogs’ disappearance.
Now, as the ice sheet in the Antarctic has reached a new all-time record size just days ago and in the Arctic the ice sheet is right on its customary path of long-term seasonal variation, none of the claimed melting-disasters appears to be happening anytime soon. I guess that’s why the computer models now predict events further and further down the road, like one thousand years from now. If they are wrong, as they most likely are, who is going to complain about these shoddy models in the year 3000?
In short, modern flame retardants like the BBs are unlikely to be damaging to frogs or other aquatic species. If the frogs’ numbers are decreasing as claimed, like for most species in that predicament, habitat loss is the main reason.
Dr. Klaus L.E. Kaiser Bio
Dr. Klaus L.E. Kaiser Most recent columns
Dr. Klaus L.E. Kaiser is author of CONVENIENT MYTHS, the green revolution – perceptions, politics, and facts
convenientmyths.com
Dr. Kaiser can be reached at:[email protected]
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