Sciencemadness Discussion Board

Lead Safety Question

statcal - 9-4-2010 at 17:44

I have a question about lead.

A friend of mine who lives with me has a piece of lead (about the size of a marble) that he cut out of a lead weight. I know people say lead is not good for humans and so, my question is, should I be concerned about him having it around/should I say anything to him about? And if I should, what is a reasonable thing for me to ask of him? (i.e. Should I ask him to simply wash his hands after handeling it and before touching things in the room? Specifically, should he not touch door knobs etc. after handling it?) I don't want to be overconcerned in approaching him about it, which is why I figured I would ask for someone's knowledgeable opinion first.

Thanks, I appreciate your help.

mnick12 - 9-4-2010 at 18:30

Welllllllllll...
You are doing good by being concerned about lead safety, but there are a few things to consider. Lead is very toxic and cumulative, but I get the feeling quite a few of these things get over exaggerated. What I mine by this is not that lead isnt dangerous but that things often get blown out of proportion. For instance I know when my grandpa was a child he and his older brother had lead solders that they made by melting lead shot in a sauce pan on their stove, and while they were alive they experienced no poisoning symptoms. So as long as you use common sense while working with lead metal you should have no problem, just wash your hands and dont chew on it.
The only time you should be really concerned is with soluble lead salts.

chief - 10-4-2010 at 01:52

My water comes through lead-pipes: Harmless, bcause of the sulfate-layer within them ...

But: A lot of people got poisoned by drinking wine from "crystal"-glass, wherin it tradittionally was stored in some countries ...
==> That crystal-glass contained lead (for high refractive index), and the lead leaked out in considerable amounts ...

They say even Beethovens deafness might have stemmed from such a poisoning ...

I my town there was a scandal, where on marihuana there was sprayed lead, to make it heavier ... : People inhaled it with the smoke, and a lot got poisoned ...

JohnWW - 10-4-2010 at 02:46

Quote: Originally posted by chief  
(cut) But: A lot of people got poisoned by drinking wine from "crystal"-glass, wherin it traditionally was stored in some countries ...==> That crystal-glass contained lead (for high refractive index), and the lead leaked out in considerable amounts ...
They say even Beethovens deafness might have stemmed from such a poisoning ...

I have some wine-glasses, from France I think, made from cut "crystal" lead glass, containing something like 20 or 30% PbO by weight. I wonder if I (and visitors) should drink from them, then.
Quote: Originally posted by chief  
In my town there was a scandal, where on marihuana there was sprayed lead, to make it heavier ... : People inhaled it with the smoke, and a lot got poisoned ...

If that happened, the people who got Pb poisoning, presumably diagnosed by blood tests after visiting their medical doctors complaining of neurological symptoms, as the result of smoking Pb-laced pot could have hardly complained to the local Pigs! They themselves would have been arrested for possessing and smoking pot, so I presume that the pot-growers who sprayed a Pb compound on their pot plants to increase the weight of their harvest go away scot-free.

I wonder, also, if the Pb compound the pot growers used on their plants was, in fact, lead arsenate(V), Pb3(AsO4)2, which would have been even more poisonous than other Pb compounds. It is used as an insoluble surface insecticide on fruits, sprayed as a suspension to protect against chewing and burrowing insects such as the larvae of codling moth and fruit-fly, but it has gone out of favor due to its having to be washed off ripe fruit when picked.

[Edited on 10-4-10 by JohnWW]

chief - 10-4-2010 at 03:53

You definately should not drink from those glasses ...
==> A single drink from them may contain tens of mg(!) of lead, as I read somewhere ... ; but maybe this was for portwine which was allowed to stand for a while in such glass ... ...

Maybe a low acid wine, drunken within a short time after filling it in, will not harm ...

===============
The lead in the marijuana was even in the news here ... ; doctors hadn't seen such poisoning ever, and at first coldn't find the reason, until soeone gave them a probe of the stuff he had smoked ... ; numerous people were poisoned ...

[Edited on 10-4-2010 by chief]

hissingnoise - 10-4-2010 at 05:12

Quote:
My water comes through lead-pipes: Harmless, bcause of the sulfate-layer within them ...

It might be a good idea to check the possibility of having them replaced.
A change in pH of the water could be dangerous to anyone drinking it. . .


unionised - 10-4-2010 at 05:50

If much lead was being dissolved from the glasses they would be "frosted" and you would see this.
It is possible to leach lead from crystal glass but you need to leave it soaking for a long time. Decanters might be a problem, but glasses aren't.

Does anyone really think lead crystal glasses would be on the market if they poisoned people?

A related issue is home- made pottery with glazes that contain a lot of lead compounds.

To get back to the OP the best answer is to wash your hands after handling lead and, preferably, not to handle it if you have any cuts or grazes on your hands

densest - 10-4-2010 at 12:50

@unionised - Yes, the glasses are still on the market, and yes, lead does leach out in substantial quantities if anything acidic is left in a lead-glass container for more than a few hours. There have been a number of public health warnings about this. A glass of wine poured and drunk isn't really a problem. Decanters storing wine and crystal baby bottles are.

AFAIK, a lock of Beethoven's hair was analyzed and found to contain enough lead ingested continuously for years to have thoroughly poisoned him. His deafness is a typical symptom of lead neurotoxicity. It's quite possible that his depression was another symptom.

While acute lead poisoning is easy to diagnose, chronic subclinical lead poisoning is subtle, pervasive, and obscure. The effect of minute amounts of lead on childhood brain development is cumulatively severe. Measurable effects include 10 points of IQ, intractable behavioral problems, etc. Current medical thinking suggests that, like arsenic, lead in water should be as low as possible, since lead in ppb amounts can have measurable effects.

Lead was known to be poisonous many hundreds of years ago, yet it was added to wine to sweeten it centuries afterwards. The stereotype English aristocrat with gout really had been poisoned by the lead in his port wine. Old bottles have been sampled and have 100s of ppm of lead. This came from the brandy added which had been distilled in lead-soldered stills.

A truly sad practice still continues: lead-based stomachache cures given to children. The big problem is that it works, so it's very hard to eradicate. I saw litharge offered in a catalog of herbs aimed at a Spanish-speaking market.

I'll reiterate: chronic lead poisoning is very difficult to diagnose. It may present as dozens of different symptoms, usually diffuse and hard to characterize. In infants and young children the effects on brain & nervous system development are subtle, severe, and incurable.

The body has no effective pathways to isolate and excrete lead and arsenic, so they accumulate and are only excreted accidentally. Many lead compounds taste sweet so there is no warning from bitterness or sourness as other toxic metal compounds exhibit.

States in the US are starting to require hazmat type containment around carpentry work done on old houses presumptively assumed to be coated in lead paint. Some already require encapsulation or removal of lead paint in houses where young children live. It's not an overreaction IMHO.


Rosco Bodine - 10-4-2010 at 23:09

Tetraethyl lead was used for decades as a gasoline octane improvement additive and literally millions of tons of lead was dispersed into the environment as an aerosol of the lead oxide resulting from the burning of "ethyl" gasoline.....
therefore if the danger of lead toxicity was as extreme as some hysterics would propose, most of humanity living in the industrialized world would have long ago already been dead from exposure to the lead which was so much more extreme before the use of unleaded gasoline became required.
Likewise the same is true for mercury, and while toxic levels of any metal are very possible and undeniable for exposures that are high enough, cadmium, antimony, chromium, arsenic, ect. can all be very toxic too, the truth is that a thousand other various sorts of life enders have far more likelihood of causing anyone's death.

Every human being has a built in and genetically coded range of "operational lifespan" or "design life" beyond which death is certain, as our "shuffling off the mortal coil" which is that spiral helix of DNA running its countdown like a clock. So death is a mathematical certainty, due to the replicative error of the cells which do replicate when worn out, and the
normal attrition due to old age of the cells which do not replicate and eventually reach "end of mission". Generally a combination of those things will with certainty bring an end of life for the body, even when no environmental factors are present to have great effect on changing that timetable for better or worse. Doing the algebra on where exactly is the tradeoff for economy and quality of life versus longevity with regards to "industrial pollutants" is of course a dilemma for reasoning men, while hysterics and "purists" have a different perspective for not being encumbered by any sense of practicality. Utopia can always be engineered successfully achievable in the minds of lunatics, so that absolute purity is attainable as the goal even if kills all humanity to achieve it.

[Edited on 11-4-2010 by Rosco Bodine]

chief - 11-4-2010 at 01:58

People don't get dead from lead -- they get dumb: There is even a saying: "Dumb as a printer", for in the past printers had regularly lead-poisonig from the letters of which they were setting the pages for the book-press ...
==> That dumbness came from the lead ...

plastics - 11-4-2010 at 08:08

Rosco Bodine - well said. Now its time for a beer and a fry up

JohnWW - 11-4-2010 at 14:03

By the way, "lead poisoning" is a known euphemism for being simply shot to death with bullets. But it has a literal meaning, in that wild game shot with many Pb bullets, or Pb pellets from shotgun cartridges, but surviving, can theoretically die later from lead poisoning, that is, if they are not killed by septicemia resulting from their wounds. This is why Pb bullets and shotgun pellets have been banned in many places, being replaced by mild steel; or much more expensively, replaced by bismuth (which is unsatisfactory because Bi is also toxic and it is a rare metal in fairly short supply).

hissingnoise - 11-4-2010 at 14:34

Quote:

therefore if the danger of lead toxicity was as extreme as some hysterics would propose, most of humanity living in the industrialized world would have long ago already been dead from exposure to the lead which was so much more extreme before the use of unleaded gasoline became required.

The cretinism caused by past exposure to airborne lead compounds isn't easily quantifiable but I'd guess it must have been fairly considerable. . .

statcal - 11-4-2010 at 16:03

Thanks for your input, I appreciate your responses.

Rosco Bodine - 11-4-2010 at 17:39

When dining on quail or pheasant having been earlier taken in the field by a hunter and dog, sometimes the teeth may encounter a shotgun pellet of lead
while chewing the meat but it should cause no alarm. Manners requires that one should not make much of it but simply pluck out the pellet or spit out the biteful, as most people do not have the oral dexterity with so dense a pellet as to blow it forcibly from the mouth through pursed lips as would typically be done with a watermelon seed. It is something of a parallel to finding a pearl in an oyster,
there may sometimes be a failing in the interception of such occasionally to be expected intruders, but one should not be distressed over such matters when missed, as sometimes they just slip by barely noticed, having faith that in time they will pass.

Jor - 12-4-2010 at 01:22

Quote: Originally posted by JohnWW  
By the way, "lead poisoning" is a known euphemism for being simply shot to death with bullets. But it has a literal meaning, in that wild game shot with many Pb bullets, or Pb pellets from shotgun cartridges, but surviving, can theoretically die later from lead poisoning, that is, if they are not killed by septicemia resulting from their wounds. This is why Pb bullets and shotgun pellets have been banned in many places, being replaced by mild steel; or much more expensively, replaced by bismuth (which is unsatisfactory because Bi is also toxic and it is a rare metal in fairly short supply).

Strangely, while all the heavy elements surrounding bismuth in the periodic table are toxic, bismuth is actually virtually non-toxic, so it's used in bullets now, and also as a replacement for lead sometimes in solder.
It's quite funny that the metal is quite cheap while it is extremely rare, it is together with Te the rarest element after the PGM's, Re and Au, wich all cost a lot.

JohnWW - 12-4-2010 at 07:20

Yes; I am aware of the rarity of bismuth, which is all the more reason why the stuff is really too valuable to be wasted for such a purpose as bullets and shotgun pellets, very little of which can ever be recovered after use in firearms. More important uses of Bi, from which it could eventually be collected and recycled, are in specialized fabrication alloys such as in solders where Pb cannot be used on account of its higher toxicity or other properties, and as a laboratory and industrial reagent (although in its use as bismuthate(V) for the colorimetric analysis of Mn in aqueous solution it can be substituted with plumbate(IV)). It may possibly find some use as a low-band-gap semiconductor in combination with a trivalent element, possibly boron. This is why mild steel should be used instead of both Pb and Bi in ammunition, in spite of its higher melting-point.

I suppose depleted U-238, with a density of 19 which is much higher than that of Bi or Pb or Fe, could be used instead in bullets and shotgun pellets, but it also has a much higher melting-point and is much harder, and it is fairly reactive and VERY chemically toxic which would result in substantial environmental damage after a while, in spite of its low radioactivity (at least before decaying after billions of years). The use of depleted U-238 as the casing or tips for explosive shells, such as in Bu$h's Iraq war/whore, on account of its high density and hardness, is much worse still, because the explosive charges and impacts on hard surfaces results in the U-238 in such shells being atomized and partly oxidized to UO2 and UO3 as a fine powder or dust, making it even more widely dispersed and chemically reactive than if it were used in ordinary non-explosive bullets or pellets. In places where the stuff has been used in shells in Iraq, there have been very large numbers of serious birth defects, so much so that people in those places have been advised to not have babies.

Panache - 12-4-2010 at 09:03

Quote: Originally posted by JohnWW  

.......so that people in those places have been advised to not have babies.


and we know how effective advice like that is.

densest - 12-4-2010 at 15:32

In Public Health Reports Vol. 115 Nov/Dec 2000 pp 521-529, by Lanphear et al, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1308622/pdf/pubh... what appears to be a well conducted study says:
Quote:

Results. The geometric mean blood lead concentration for children in the
study sample was 1.9 ug/dL; 172 (2. 1 %) had blood lead concentrations >= 10.0
ug/dL. After adjustment for gender, race/ethnicity, poverty, region of the
country, parent or caregiver's educational level, parent or caregiver's marital
status parent, serum ferritin level, and serum cotinine level, the data showed
an inverse relationship between blood lead concentration and scores on
four measures of cognitive functioning. For every ug/dL increase in blood
lead concentration, there was a 0.7-point decrement in mean arithmetic
scores, an approximately 1-point decrement in mean reading scores, a 0.1 -
point decrement in mean scores on a measure of nonverbal reasoning, and a
0.5-point decrement in mean scores on a measure of short-term memory.
An inverse relationship between blood lead concentration and arithmetic
and reading scores was observed for children with blood lead concentrations
lower than 5.0 ug/dL.
Conclusion. Deficits in cognitive and academic skills associated with lead
exposure occur at blood lead concentrations lower than 5 ug/dl.

Perhaps the raging stupidity of the planet has a chemical cause? I dunno, but this is suggestive. Other studies have shown that proximity to highways raised lead levels but I don't have a reference for that one.



[Edited on 12-4-2010 by densest]