Bill
Sorry! 3 orders of magnitude out: I said 5 g!
Brian
Bill Hampshire wrote:
>
> Hi all,
>
> Ingest 5 mg of tin compounds? Sounds like a piece of cake!! (so to speak)
>
> Diet studies are notoriously difficult, but one I saw a while back said
> that the average UK resident ingested about 3 mg daily as part of the
> "normal" diet. This is in the form of compounds inside canned foods (or
> maybe baking pan linings or large mixing bowls or nicely tinned pans, who
> knows). So, allowing for diet changes since then, it is reasonable (in
> my opinion) to guesstimate that each of us consumes about half that 5 mg
> every day, anyhow. Certain tin compounds are, in fact, allowable food
> additives on account of their color- and taste-preserving properties -
> see the US Code of Federal Regulations.
>
> In fact, since this is a fantasy forum (or so I have read), let me
> subject you to my favorite tin chemical toxicity anecdote:
>
> Back in the 1980's the good people at ITRI (Tin Research) found that tin
> chemicals were good fire-retardants (FRs) in a variety of materials. Our
> branch office here in the US was part of the marketing effort, of course.
> One of our primary concerns was potential toxicity (yes, even in the
> Reagan years), since that was/is questionable for the current FR
> chemicals. We convinced the powers-that-be in Uxbridge to part with some
> funds to a local university to determine toxicity of the sodium and
> potassium stannates. A rat feeding study was done and the surprising
> results will hearten all you rat-lovers out there, although dismay the
> SPCA on account of animal cruelty. The preliminary round of testing
> produced no useful results, so the university people found they had to
> load up the rats with chemical, to the point that they reported the rats
> were sluggish from the sheer weight of their stomach contents. But, upon
> dissection, there were still no toxic effects found. So, they reported
> officially that the LD50 was greater than the highest level of feeding
> they used (they did not say much greater), and advised ITRI that it would
> be a waste of time and money (not to mention rats) to try any further
> toxicity studies on these chemicals.
>
> I could go on longer, but this is enough. And about Kay's motives, let's
> hear from all those out there with the lily-white hands. Yes, go ahead
> and line up over there with all the professional environmental scientists
> that have contributed to these discussions, right beside those elusive
> OEMs. (We all have our interests, don't we? Even if it is only to keep
> blood pressure in check.)
>
> Bill Hampshire
> ex-Tin Research Institute, Inc.
> now "independent"
>
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