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Subject:
From:
Joe Fjelstad <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, [log in to unmask]
Date:
Wed, 11 Jun 2008 14:30:15 EDT
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Thanks for another interesting lesson, Brian. Your solutions seem  much too 
simple. Control the process?... Ah, would that we could... ;-) 
 
Incompletely cured laminate material was a concern some years back when  
demand was high and some short cuts were apparently taken to full orders  from 
impatient customers. We used to do a lot of baking of laminate before  processing 
just to make sure it processed correctly.
 
On the other point of concern, how again was it that human infants  were fed 
over most of history? 
 
As long as the government wants to get so deep into our lives, perhaps a  new 
law requiring mothers to feed their children according to nature? 
 
Rousseau would certainly approve. It seems that perhaps to some  extent, 
Rousseau is presently being channeled by some EU  legislators who wish for us to 
return to our noble savage roots. 
 
And so it goes....
 
All the best, 
Joe
 
 
 
In a message dated 6/11/2008 12:23:03 A.M. Pacific Daylight Time,  
[log in to unmask] writes:

Worse,  Joe: I was watching a consumer's programme on Swiss TV last 
night.  Apparently, a prof. at Columbia university has discovered that 
some  babies' feeding bottles in polycarbonate transfer infinitesimal 
quantities  of bisphenol A to the contents. This is claimed to cause 
hormonal  development problems to the baby, creating overgrowth and 
obesity to the  infant, as "proved" in rodents (no mention of dosology or 
metabolic paths,  necessary in serious toxicity or epidemiological studies).

As a result,  polycarbonate bottles are now being forbidden in Canada.

The programme  anchor, who is an anti-everything by nature, then bought n 
bottles in  Switzerland  and had a German lab (more serious than a local 
one, of  course) determine which ones were in PC, which in other unnamed 
plastics  and which in glass. The majority were in PC. However, she 
reported no  figures of BPA leaching, so all the PC ones were condemned 
without   trial. She recommended that mothers use only glass (why not, 
anyway???).  BTW, no thought about the titties that actually go in the 
childrens'  mouths and what they may be made of!

She then interviewed a so-called  expert, a professor in some obscure 
university, I think in France or  Belgium, who claimed that BPA was one 
of the worst chemicals in existence,  carcinogenic to umpteen organs, 
mutagenic, teratogenic, endocrine  upsetter, neurotoxic, reproductive 
toxic and causes nearly every other  disease known to man, including 
Alzheimer's and Parkinson's (yes, he  recited this list except the every 
other disease bit which I added). No  mention of dosages, though. Now for 
the bad news: this guy claims to have  the ear of the EU and wants BPA 
and products made with it banned  throughout the Union.

That means all polycarbonates, epoxies and some  copolymers are currently 
under scrutiny. No DVDs or CDs, no FR-4 or epoxy  adhesives, no PC 
monitor cases, no plastic glazing or greenhouses, no  cars, no aircraft, 
no polycarbonate capacitors, no FR-4 of any flavour  etc... Back to our 
caves, guys!

Now, a wee bittie of simplistic  chemistry. To make FR-4, a mixture of 
BPA and its brominated homologue  TBBPA is reacted with epichlorohydrin 
in the presence of sodium hydroxide  to form the basic prepolymer, which 
is treated in various ways to  eliminate most of the sodium chloride 
which is formed. Theoretically,  there is no free BPA/TBBPA left if the 
proportions are stoichiometrically  correct. This prepolymer is then 
reacted with a crosslinking agent which  joins up the linear liquid 
prepolymer, via the epoxy groups in the  molecules into a 
three-dimensional polymer.  In the case of  polycarbonate, it is formed 
by a similar condensation reaction with BPA,  often admixed with TBBPA. 
If there is any free BPA or TBBPA, it is because  either a) there is an 
excess beyond the stoichiometrical ratio or b) the  polymerisation 
reaction is incomplete. b) is easy to control but a) less  so but a) can 
be stopped by adding a very small excess of its reactant,  
epichlorohydrin in the case of epoxies, so that it is all reacted. As  
the latter is volatile, any excess will be eliminated during the curing  
process or any subsequent heating. I maintain that it is not necessary  
for polycarbonate or epoxy resins to have excessive quantities that can  
leach out, but it will require better process control, but it is much  
easier to prevent the problem by banning BPA and its brominated  derivative!

For those who understand French, you can see the report at  
http://www.tsr.ch/tsr/index.html?siteSect=500000&bcid=590635#bcid=590635;vid=9
199328
(if  the URL is split, don't forget to join the lines)
Also  
http://www.tsr.ch/tsr/index.html?siteSect=311201&sid=9198628&page=1#title
for  a summary

I hope this is nothing more than a storm in a baby's  bottle!

A bon entendeur, salut!

Brian

Joe Fjelstad  wrote:
>  
> for your  consideration...
>  Joe
>  
http://www.edn.com/blog/570000257/post/1740027974.html?nid=3357&rid=208605613
>  Tuesday, June 10, 2008
>  
> Flame retardants ignite   controversy
>  
> Jun 10 2008 7:31AM 
> Accurate  figures are difficult to obtain, but it has been estimated that  
>  fires kill around 10,000 people a year globally, in which the cause is   
> attributed to faulty electrical wiring in buildings and in electrical  
equipment.  Flame 
> retardants have been used very effectively in  a wide variety of electrical 
 
> equipment to prevent fires, reduce  their seriousness and also to delay 
onset to 
>  allow people more  time to evacuate. In fact, research has shown that when 
> flame   retardants are used as additives to plastics, the amount of time to 
>  escape is  increased by 15 times. Since they were introduced, thousands  
of lives 
> have been  saved, and so there is no doubt about their  value. 
> Many types of plastics burn very easily. It has been estimated  that the  
> plastics in a typical TV set are equivalent to 1.5  gallons of gas, not 
something  
> consumers want in their living  rooms!  However, only around 12% of 
plastics  
> contain flame  retardants. Some types are inherently resistant to fire, 
such as   
> rigid PVC, and so do not need flame retardant additives. Some  equipment is 
> not  at risk such as battery powered products like  mobile phones because 
of the 
> low  voltages used, and therefore  flame retarded plastics are not needed. 
> Mobile  phone battery  chargers, however, do need to have flame retardants 
as they 
> are   powered at standard voltages, and so arcing and high temperatures can 
>  occur if  there is a defect. 
> But BFRs (brominated flame  retardants) are now at the center of 
considerable  
> debate. The  review of the ROHS directive, undertaken by the German 
>  organization  Oko on behalf of the European Commission, is looking at a  
significant 
> number of  them, along with 46 other chemical  compounds, and may well 
recommend 
> the  restriction of some, or  all of them. 
> So, why will they be banned when many have already been  tested, and it was 
 
> concluded that they pose no threat to human  health and the environment? 
> Well, Oko is recommending a ban on all  organobromine and organochlorine  
> compounds, including  brominated flame retardants because of �backyard 
recycling�  
>  of WEEE (Waste Electrical and Electronic Equipment) in countries that do  
not  
> have the know-how, or facilities, to dismantle safely.  
> The toxic fumes created by backyard and roadside fires are having  a  
> significant affect on human health, even causing death.  
> While the Basel Convention should stop the shipping of WEEE to  such  
> countries, a lot of the scrap still comes from the likes  of the United 
States,  which 
> has not yet ratified it. 
>  Flame retardants seem a classic example of a need for a risk-benefit  
balance  
> based on assessments that the ROHS directive and REACH  regulations were 
> designed  to resolve. It�s a trade-off  between safe furniture, fabrics, 
and 
> electronics or  the  fatalities caused in the poorer villages of China, 
India, and 
> Africa.  
> 
> 
> 
> 
> 
> 
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