Dear Chuck, all,
(I really hope i dont spam leadfree list with this conversation)
I am sorry that my Latin is as bad as my English (I know most of it from
Asterix comics)(the Latin!)
1. I remembered "stochastic" from my statistics lectures to mean
"random"; unpredictable; same cause with different results when you
repeat it (not easy for an engineer...). Sometimes, the gene is damaged,
sometimes not. And sometimes it is repaired, and sometimes not. Repair
is not 100%. Therefore, some of the damage will remain, even if the
number of the damages (and the dose)was very low.
2. Be careful with the oxygen-experiment!
3. A thing often heard at the list: "Nature does xyz, so why shouldnt we
be allowed to do the same". I understand your former remarks about
"natural" and "anthropogenic" lead emmissions in that way: There is so
much natural lead, why should we be afraid of this little anthropogenic
amount? I want to emphasize, that in this case, the anthropogenic amount
is large. To lower it, lead was banned from gasoline, paint, ammunition
- and electronics... maybe inefficient but not so totally illogical as
often stated in the list.
If we have natural sources of certain dangereous effects, wouldnt it be
better to ad as little as possible to it, instead of trying to "hide"
anthropogenic emissions in a natural background - at least where
possible?
Side note: I appreciate the growing interest in life cycle assessment,
but not only lead-free products have a life cycle.
4. Obviously, lead BECOMES more mobile when touched by man - it is
transported, manufactured, chemically transformed, emmitted,
distributed, thrown away, picked up again, etc. And if it ends up in a
landfill, there are even chances that it "becomes more water soluble",
because "water" in a landfill is something else than "water" in a
geological deposit. Some Latin training again: "Quod licet jovi, non
licet bovi." - What the one (nature) is allowed to do, is not
necessarily allowed for the other (mankind), or something like that.
5. One off-topic:Elsewhere, you quoted this nice aphorism "Programming
today is a race between software engineers striving to build bigger and
better idiot-proof programs, and the Universe trying to produce bigger
and better idiots. So far, the Universe is winning."
Could it be possible that this is from a software engineer? And, if so,
aren't software engineers products of this Universe, too? After Win
3.11, 95, 98, NT, ME, XP, 2000, I dont believe in the infallibility of
programmers anymore. Same is true for other technologists that say that
their customers are too dumb to use the product (They could have told
them BEFORE selling the product...).
BEst regards,
khz
Original message from Chuck Dolci:
Karl:
Karl Heinz Zuber wrote:
> 1. the old "dosis venenum facit" (The dose makes the poison) is not
> ALLWAYS true. There is, as far as i remember, one mechanism where
there
> are no safe limits: If genes are affected, the repair mechanisms as
well
> as the damaging mechanisms are stochastic. That means that even one
> molecule of the substance can cause damage, and the safe level is 0.
> Probability of effect is of course lower with lower doses.
> MERIAN ("Metals and their compounds in the environment", VCH, 1991)
> (this one is in english ;-) mentions some evidence for genotoxic
effects
> of lead and several compounds.
"dosis venenum facit" It always sounds better in French doesn't it?
I am not clear on your point.
stochastic - adj. 1. Of, relating to, or characterized by conjecture;
conjectural.
How does that lead to the notion that, with respect to genes, "...even
one molecule of the substance can cause damage, and the safe level is
0." ? Genetic material - DNA - is being damaged all the time, mainly
from natural, internal sources. The largest source of damage to DNA is
oxygen radicals, a product of metabolism. I have not yet concluded my
research on whether oxygen is essential to life, but I will report back
when I finish. I may do my own research on this, so if you don't hear
back
from me assume the experiment didn't go well.
Radiation (from natural as well as man-made sources) is also another
source of DNA damage. So is exposure to "chemicals", but that is
miniscule compared to the endogenous damage. Oxidation and the damage it
does to DNA is believed to be the single largest contributor to what we
call aging and the diseases of aging, such as cancer. That is why
everybody is hyping "antioxidants", wanting people to believe they can
forestall the effects of aging by consuming things that contain
antioxidants.
However, the body constantly repairs the damage to DNA. Bottomline is
that lots and lots of things, mostly natural and mostly internal, cause
DNA damage and the body is constantly repairing it, so the idea that any
dosage above zero irreversibly damaging the genes is just not valid
(otherwise many of the natural foods we eat would be off limits, as
would breathing).
>
>
> 3. One more from MERIAN: The increase of lead in sediments during the
> last 150 yrs was up to 20-fold, 4-fold in south pole snow. Of course
> that is due to atmospheric pollution, gasoline etc. and not to
> electronics, but it means that anthropogenic lead is not in principle
> negligible, as you implied.
The debate and my argument is not about anthropogenic sources of lead.
It is about lead in solder in electronics in landfills (numbnuts
habitually chewing on electrical wiring notwithstanding). I have never
addressed the issue of whether the total costs and burdens of removing
lead from gasoline were outweighed by the total benefits and savings to
human and animal health. That has not been the issue. We have been
addressing the issue of whether the total costs and burdens of removing
lead from
solder in electronics are outweighed by the total benefits and savings
to human and animal health.
Also, I have seen no answers to my questions about lead in solder in
landfills being more likely to leach than lead in lead sulphide or in
such other forms that may exist in nature. Is it true that lead once
touched by man becomes more water soluble and more mobile than lead
never touched by man? If so, why?
BTW I know it's Latin, just seeing who's paying attention. :>)
Best regards
Chuck Dolci
====================================================
Electronics Goes Green 2004+
Driving Forces for Future Electronics
Berlin, 6 - 8 Sept. 2004
World's leading Conference and Exhibition
on Electronics and the Environment
Contact and Informations:
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Phone: ++49 30 464 03-139
====================================================
Dipl.-Ing. Karl Heinz Zuber
Tel: ++49 30 464 03-138
Fax: ++49 30 464 03-131
Email: [log in to unmask]
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