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jubei33
13th April 09, 04:59 PM
By now, we all know about calcium and ever present dangers of hellvetica, but what of lead? Lead ranks 5th behind iron, copper, aluminum and zinc in industrial production of metals in the US. About half goes to manufacture batteries, the other half to bullets, solders and paint etc. Its uses are many and beneficial, but it is also a toxic metal we are exposed to on a daily basis. One of the most important points is that lead is readily absorbed through the lungs and intestines and has a very rapid transport to bone undergoing bioaccumulation throughout a person's life. Even though the body has useful mechanisms to remove heavy metals, it has a high half life of about 20 years in humans, with those exposed unable to easily remove it.

"I feel fine, what's the problem?"

The biggest, most immediate issue with toxicity is the inhibition of the production of a critical piece of hemoglobin, the heme group. Hemoglobin (http://en.wikipedia.org/wiki/Hemoglobin) is the protein in red blood cells that carries oxygen to tissues in the body. The heme group is the iron containing portion, which actually carries the oxygen, distributing it throughout the body. Without the heme group in your hemoglobin your tissues would slowly starve, wreaking all manner of havoc. Basically: no hemoglobin = no soup for you. The back up of unusable metabolic products in the liver can also damage it as well causing other problems for normal metabolism.

More so, lead causes a whole host of other problems like anemia (due to the shortening of life spans of red blood cells), largely permanent brain damage including encephalopathy characterized by neuron degeneration and cerebral edema, interference with the normal function of neurotransmitters (dopamine and gamma-butyric acid in particular) and a slew of psychological symptoms as well (restlessness, ataxia, tremor, dullness of wit, irritability, memory loss and headaches to name a few). Peripheral neuropathy is not uncommon as well, as “lead palsy” was often exhibited by lead industry workers before standards were put in placed to protect them. Kidney damage, though sometimes reversible, is another big issue with long term lead exposure causing chronic nephritis among other things.

The fact that it has a long half life in the body can lead to environmental concerns. It is widely known that lead based paint has long lasting effects on child development. (http://www.ncbi.nlm.nih.gov/pubmed/2294437) With the banning of these paint products and the use of lead based gasoline additives, a major exposure vector had been removed. Yet the problem still haunts us today. Materials painted in the past still flake and release lead into homes, lead from gasoline exhaust leached into soil and ground water is still there. There is even evidence of lead from Roman industrial smelting operations in ice cores from Greenland (http://www.light1998.com/EVENTS/Evidence_lead_pollution.htm). To give a more modern example, during the peak use of those additives in the 70’s and early 80’s, some French wines were measurably contaminated with tetra-methyl lead, a gasoline additive. Scientists at the time had measured and graphed the increasing concentration of lead per year of use of the additive, emphasizing the danger of these additives had to the people that consumed them.

http://i131.photobucket.com/albums/p297/jubei33/frenchwinelead.jpg
Lead content in certain French wines as a function of year. Nature 1994, 370, 24.

Much like an insidious bank charging fees on top of finance charges, the lead we’ve put into our atmosphere and environment has consistently come back to haunt us. People have long been aware of the problem; describing correlations between Roman use of lead plumbing and the supposed violence inherent in their society. However, without raw toxicological data for support this is still mainly speculation. In modern times, however, testing methods have greatly improved enabling us to accurately collect data on many kinds of environmental pollutants.

One man, Rick Nevin (http://en.wikipedia.org/wiki/Rick_Nevin), has recently published several papers on the topic of lead pollution and the incidence of crime. He has noted the incidence of an overall decrease in crime rates in relation to newly enacted environmental policies concerning lead. Furthermore, he also draws the conclusion that environmental exposure to lead in early development might be a cause of or statistically increase crime rates with a high incidence of child exposure. He believes that the effects of lead exposure have been underestimated and the major effect of these policies was to dramatically reduce the crime rates in the countries he studied.

A major example he studied was a policy enacted in New York City, just before Rudy Giuliani’s (http://en.wikipedia.org/wiki/Mayoralty_of_Rudy_Giuliani) now famous push to lower the crime rates in the city. The ordinance banned and forced the replacement of older, lead painted windows, which at the time was a large environmental concern in the poorer less affluent areas of the city. Nevin contends that the reduction of crime seen after the enforcement of Giuliani’s crime reduction policies was mostly the result of the new city ordinances reducing the amount of lead exposure, rather than from stricter enforcement. Despite Giuliani’s insistence that it was solely the result of his policies, Nevin purports to find similar drops in crime rate upon the enactment of better environmental policies in other countries as well.

It is possible that there is correlation between lead poisoning and criminal activity, however, the degree to which it is caused by lead is still a matter of controversy. To put direct causal relationship between the lead and between these drops in criminal activity is perhaps a difficult position to sell, because of the complex motivations and mechanisms behind it. Can it ever be truly stated that any one thing is ever the cause of some human action, at least in something as complex as crime? (e.g. Was it the fire or the smoke that made him run?) While Nevin’s studies purport to prove a causal link between lead exposure and crime, Patricia L. McCall’s work in 2008 disagrees with his assertions finding: “no support for this cohort explanation.” That said, environmental exposure to lead most definitely has an effect of human behavior, the degree of which may be decided with further research on the topic.

If one accepts the premise that to lead is toxic, then the very next idea to come to mind is how to avoid and remove exposure routes. In most western nations environmental regulations have removed the largest exposure route: lead based gasoline additives, but exposure from batteries, old paint, solder on circuit boards, contaminated ground water are still contributing factors to lifelong low-level exposure. Luckily, our bodies have systematic defenses against heavy metals, one of which is the protein metallothionein (http://en.wikipedia.org/wiki/Metallothionein). It is a medium sized protein rich in an amino acid called cysteine (http://en.wikipedia.org/wiki/Cysteine). Cysteine itself has a sulfhydral group (a S-H group) which lead and other heavy metals are chemically attracted to. Metallothionein attempts to leach lead as well as other harmful metals from the blood and remove them from the body. The binding of these metals to it greatly reduces their diffusion and blocks them from binding to other critical enzymes or proteins.

Several chemicals called chelates also use the same strategy to effect the removal of poisonous metals. Developed during WWII to combat Arsenic containing gasses, British Anti-lewisite (BAL) (http://en.wikipedia.org/wiki/British_anti_lewisite) is an often used chelation agent. It contains the same kind of sulfhydral groups in common with cysteine and can form complexes with lead and effect its removal from the body. When a chelate complex is formed with lead, the compound increases its solubility in water allowing it to be removed. Other agents include: Dimercaptosuccinic acid, EDTA and DMPS.


1. Understanding international crime trends: The legacy of preschool lead exposure (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDS-4NJP3V8-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9d17e72f0f5088f70bfd6e71e77f7e48)

2. Trends in environmental lead exposure and troubled youth, 1960–1995: an age-period-cohort-characteristic analysis (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WX8-4B6CP1M-1&_user=10&_coverDate=06%2F30%2F2004&_alid=901138955&_rdoc=1&_fmt=high&_orig=search&_cdi=7152&_sort=d&_docanchor=&view=c&_ct=1&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=4fd722ca48f85c4c54fe1cc6562c1b18)

3. Ice cores (http://www.nsf.gov/news/news_summ.jsp?cntn_id=112074)

4. Washington Post article on Nevin's Research (http://www.washingtonpost.com/wp-dyn/content/article/2007/07/07/AR2007070701073_pf.html)

5. Monetary benefits of preventing childhood lead poisoning with lead-safe window replacement (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WDS-4R05BX1-2&_user=10&_coverDate=03%2F31%2F2008&_alid=900550248&_rdoc=4&_fmt=high&_orig=mlkt&_cdi=6774&_sort=v&_st=17&_docanchor=&view=c&_ct=10&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=bbcb0ab1ca2034c04f5824e7cde48c77)

more upon request...

SFGOON
13th April 09, 06:49 PM
So, the lower the lead levels the less ludicrous the losers. While I've never heard of anything like this before, it wouldn't surprise me.

Then again, that guy Rick Nevin may have just eaten a lot of paint chips as a kid...

HappyOldGuy
13th April 09, 07:53 PM
I was expecting a font thread.

theotherserge
13th April 09, 08:44 PM
Yep, lead&other poisons in batteries. Good thing we're so certain electricity/hybrid power will save our souls...

Ajamil
13th April 09, 09:58 PM
Yep, lead&other poisons in batteries. Good thing we're so certain electricity/hybrid power will save our souls...

Electricity is fine, getting it from batteries maybe not so much.

Also, there's a public message billboard up near my house about lead - it makes no sense and is bad marketing, other than every time I see it, I'm reminded for several minutes how horribly it conveys it's message.

EuropIan
14th April 09, 05:29 AM
Jubei33 loves his mothafuckin lead.

Interesting read.

Why was lead used in gasoline?

SFGOON
14th April 09, 06:21 AM
For evil corporations of some sort, no doubt!

EuropIan
14th April 09, 06:55 AM
Yeah the heavily subsidized lead farmers were producing too much so they lobbyed the gov'ment so they could sell and distribute it to many of the important industries in the us, such as paint and gasoline refinement.. umm yeah.
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Is it because it's a catalyst of some sort?

Aaranar
14th April 09, 07:42 AM
Why was lead used in gasoline?

Boosted octane levels.

jubei33
14th April 09, 09:06 AM
So, the lower the lead levels the less ludicrous the losers. While I've never heard of anything like this before, it wouldn't surprise me.

Then again, that guy Rick Nevin may have just eaten a lot of paint chips as a kid...

Yeah, that's basically the gist of his research. He's making a supported argument, that might not have enoguh evidence at present to seal the deal to legislate so to speak. Its not out of the ballpark, conspiracy theory territory, either. Its just plain hard in any respects to pin down cause, especially at the levels studied. The issue is two-fold: legal limits might be a little high according to new research and our ability to accurately measure those lower levels has increased.

a lot of legal safe limits were written in the 70's and 80's, but at the time PPM was just barely measurable. Today most modern equipment measures PPT level with no problems and the size is smaller too. I was lucky enough to work in a lab that had 30 years of mass spectroscopy in the same room. There was the old TAGA, which was the size of a really small car, the API-365, which fit an a long table and they were running tests on a state of the art, ion trap model which was the size of a PC (incredible resolution to boot).

some of what they're finding now is that chronic low level exposure to certain chemicals might have dangers aside from just a large acute exposure that has enough juice to cause cancer or other trouble in its own right. There's a lot of research pouring into things like endocrine disruption, for example, and we might find that our original estimates of safety will have to be reworked.

Another interesting point is the amount of politics that goes into these regulations. In the 50's, during the atomic testing/atomic veterans issue the governments estimates of safe exposure were wildly all over the place. It wasn't until later they were replaced with safer standards. If you read a little more on the subject, one could paint a very dark picture on the government's motivations to deliberately keep it high.

jubei33
14th April 09, 09:27 AM
I was expecting a font thread.
I was going to write it in helvetica, but it looked all funky. You got to watch Ian's clacium video to get the joke.


Is it because it's a catalyst of some sort?

No, not a catalyst in this instance. A catalyst is a chemical that is involved in a reaction that isn't used up or changed to something else in a reaction. Typically they give a place for a reaction to take place. for this reason they're usually finely ground powders to increase the surfce area and give the reaction more opportunity to take place. They are often transition metals that can form complexes with one of the chemicals in a reaction, which might change its shape to conform to some other desired shape. Platinum works in this way via hydrogenation, its called a syn-addition if you want to look up more info.

electricity is a flow of electrons, batteries work by moving electrons from one metal to another. Lead in a battery works via this reaction:
Pb(s) + HSO4-(aq) + H2O(l) -----> PbSO4(s) + 2e- + H3O+
the laed gives electrons to power the happy fun-fun mobile's alternator.


Jubei33 loves his mothafuckin lead.

I had this floating around up here from an argument we all were having here like a year an a half ago about crime or somthing (forgot actually) and it just kept popping up again. So maybe now I'll be free of it or just be the lead guy on sociocide...?

theotherserge
14th April 09, 09:33 AM
Re: atomic power, Richard Rhodes is a must read for development of the Atom&Hydrogen bomb.

As for Arjuna, I think it's hilarious that a lead warning sign makes no sense. Maybe that's the warning...

jubei33
14th April 09, 09:51 AM
Yep, lead&other poisons in batteries. Good thing we're so certain electricity/hybrid power will save our souls...

Not so much of a problem if we have a better means of production and recycling the old ones, rather than dumping them in places like the Dominican republic (http://www.miamiherald.com/americas-special/story/39816.html). Something I didn't know is apparently, in the US "Lead-acid batteries are the environmental success story of our time (http://www.batterycouncil.org/LeadAcidBatteries/BatteryRecycling/tabid/71/Default.aspx). More than 97 percent of all battery lead is recycled." hmm touche~

Also, hybrid batteries use nickel-magnesium, which have toxic compounds as well, but the thing to realize is that nearly every element has toxic compounds of one sort or another.


As for Arjuna, I think it's hilarious that a lead warning sign makes no sense. Maybe that's the warning...

IS a picture worth a 1000 words? Time may tell...

Ajamil
14th April 09, 02:36 PM
No, it's three kids playing with construction toys in a sand box, and the words are :

Lead Poisoning Affects All Ages

And the info on who put the board up, and where to go for lead knowledge.

I mean, are the toys lead (best bet, maybe jabbing at China)? The sand? Are the kids lead-stupid? What?

jubei33
14th April 09, 04:26 PM
have you perhaps eaten lead paint; effects manifesting as a deficit in reading comprehension?

no, just kidding.

toys from china were of a concern a while back, because they were using lead paint to color them. Some people were and possibly are buying them second hand in garage sales, etc. stores were banned from selling some of them as the companies hadn't changed their manufacture processes. As far as I care to find out, they may still use the same in products they sell in China.

Not on the same subject, but another concern was poorly manufactured plastic toys. When exposed to sunlight, some of them can evolve a small amount of formaldehyde, a chemical traditionally used as an embalming fluid until its toxicity was noticed. This goes along with the 'chronic low exposure' theory mentioned above.