The glass chemistry is really the issue. Glasses properly formulated with other large cations, can very effectively block Pb leaching even in very acidic or alkaline environments, even in granulated form. The question is whether the CRT glass was formulated as such, since it was not intended to be used for drinking glasses, or pottery glaze.
Best regards,
Leo
Leo M. Higgins III, Ph.D.
Sr. Vice President, Engg and Technology
ASAT, Inc.
13809 Research Blvd., Suite 635
Austin, Texas 78750
office phone 512-249-4758
mobile 512-423-2002
[log in to unmask]
www.asat.com
-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Brian Ellis
Sent: Monday, December 11, 2006 10:15 AM
To: [log in to unmask]
Subject: Re: [TN] The 'poisonous'- computer reports
I disagree about the bioavailabilty. In a landfill, the lead glass is
inevitably crushed into small particles the total surface area is
therefore very large. As lead glass is slightly water soluble, the lead
can enter into run-off over a matter of years. What happens to this
water is the nux of the problem.
I agree that the quantity of lead in a modern computer is small, but
what about the zillions of CRT monitors still in use?
Brian
Thompson, David wrote:
> Glen / Ingemar: CRTs do not contain layer of lead coating inside the
> tube. The lead is contained in the glass and is not readily
> bioavailable in a landfill environment.
>
> Today's computers probably do not contain 1/2 pound of lead.
> Panasonic's current line up of laptops contain about 5 mg, a long way
> from 1/2 pound.
>
> David Thompson
> Panasonic
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Glen Herzog
> Sent: Monday, December 11, 2006 10:15 AM
> To: [log in to unmask]
> Subject: Re: [TN] The 'poisonous'- computer reports
>
> Ingemar, possibly this article is suspicious because it was written in
> 1996, long before LCD screens and long before the introduction of RoHS &
> WEEE. CRTs have a heavy layer of lead in coating the inside of the
> envelope. I'll bet that todays lead weight in a desktop would not
> exceed
> 1/2 pound.
>
> Table presented in: Microelectronics and Computer Technology Corporation
> (MCC). 1996. Electronics Industry Environmental Roadmap. Austin, TX:
> MCC.
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e
> 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
> -----------------------------------------------------
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e
> 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
> -----------------------------------------------------
>
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
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
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
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
-----------------------------------------------------
|
