In view of some of the recent dialog, it seems worth while to go back to
square one for a moment to recheck the facts and the assumptions.
The precautionary principle is being misapplied to elemental lead.
We know very much about lead. Lead is, after all a simple element. Atomic
number 82 on the periodic chart of elements. It is natural part of the earth's
make-up and has been in use by the earth's peoples for 6000 years. The
majority of lead's natural salts and its oxide have very low solubly. It thus does
not leach into ground water. It melts at relatively low temperatures made
lower by the addition of tin. It is an excellent low temperature joining
material. It is not expensive and it is easy to recycle. These facts have been known
for many decades if not centuries.
We have also just learned that it is essential in mitigating tin whiskers,
which as contact pitch are reduced, the risk of which is looming larger as
July 1 rolls nearer. But this is specific to electronics manufacturing and the
reliability if the products.
Elemental lead's most often (unfortunately) proven toxicity, responsible for
the deaths of millions, is when it is propelled at high velocity into a
living being (e.g., bullets). Elemental lead can also be toxic if ingested and
gets stuck in the alimentary canal, especially in the stomach. Additionally,
lead can be toxic if it penetrates the bone marrow and is not removed. These
are documented conditions for elemental lead toxicity.
Organic lead has been a different matter.
The point of concern and the lead-free movement was predicated in concern of
the poisoning of children, especially the very young, in early, formative
years, where the effects are most pronounced. Nearly all cases poisoning of
children have been due to the ingestion of lead acetate used in paint. Acetic
acid (aka vinegar) will dissolve lead to form lead acetate (aka lead sugar) It
was used in paint and paint chips are sweet. Lead acetate was even used to
sweeten wine in centuries past. Also there is tetra ethyl lead which was (and
still is in some places) used as an antiknock in gasoline (petrol, benzene)
This can be inhaled from fumes of combustion and an accumulation of lead in the
body. Neither of these have the remotest relationship to electronics save
that the element lead was used in the creation of the organic products.
Elemental lead does not require the employment of a precautionary principle.
It simply requires due caution.
Man made compounds, especially those without known analogues do require
precautions.
In sum lead-free solder will not make the environment better, but it could
well make it worse. It will not use less energy, it will use more. It will not
be cheaper, it will be more expensive. It will not make electronics more
reliable, evidence is that it will make them less so. However, the crowning
point is that the provisions of WEEE which require recycling, makes the matter of
lead from a risk point totally moot while the negatives and risks associated
with going lead-free, in terms of electronic solders, will remain.
I don't want to get wrapped up in legal wrangling. The facts speak very
clearly for themselves. The question is will the EU, and those who support the
EU's decision, accept the facts over their prejudices.
Kind regards,
Joe
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