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. > > > > > > > **************Vote for your city's best dining and nightlife. City's Best > 2008. (http://citysbest.aol.com?ncid=aolacg00050000000102) > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 15.0 > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 > ----------------------------------------------------- > **************Vote for your city's best dining and nightlife. City's Best 2008. 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