QUESTION: Which type of 'removal system' would be safest for an 83 year old man with suspected high levels of lead? 02/11/09 Greater London, UK - United Kingdom

I would like to know your views regarding lead toxicity and IV chelation. Do you believe that if a person has very high levels that the chelating agent may not be enough to cope and that some of the lead could cross the blood brain barrier.

Also, can you tell me what tests you would recommend to determine lead toxicity prior to removal of lead

Can you also tell me which type of 'removal system' you think would be safest for an 83 year old man with suspected high levels of lead.

I thank you in advance for your response as it is very important to me asthe person in question is my father who worked until he was 83 years old and I want to do everything I can to help him.

Marjorie

ANSWER: Nov 3 2009

Dear Marjorie,

when I received your question I looked up blood brain barrier in "the bible" on lead's health effects, "Toxicological Profile for Lead (August, 2007)[582 pp]" from http://www.atsdr.cdc.gov/toxprofiles/tp13.pdf by the Agency for Toxic Substances and Disease Registry (ATSDR) in the USA and found the following:

[page 236/582] "Thus, it appears that premature activation of PKC [protein kinase C] by lead may impair brain microvascular formation and function, and at high levels of lead exposure, may account for gross defects in the blood-brain barrier that contribute to acute lead encephalopathy. The blood-brain barrier normally excludes plasma proteins and many organic molecules, and limits the passage of ions. With disruption of this barrier, molecules such as albumin freely enter the brain and ions and water follow. Because the brain lacks a well-developed lymphatic system, clearance of plasma constituents is slow, edema occurs, and intracranial pressure rises. The particular vulnerability of the fetus and infant to the neurotoxicity of lead may be due in part to immaturity of the blood-brain barrier and to the lack of the high-affinity lead binding protein in astroglia, which sequester lead."

[page 242/582] "This suggests that children are more vulnerable to absorbed lead than adults. The mechanism for this increased vulnerability is not completely understood. Lead affects processes such as cell migration and synaptogenesis, as well as pruning of unnecessary connections between neurons, all key processes during brain development. Lead also affects glial cells and the blood brain barrier. Alterations in any of these parameters can produce permanent improper connections that will lead to altered specific brain functions."

All the above tells me is that it is the lead poisoning that causes the lead to cross the blood brain barrier, not the inappropriate dose of the chelation agent. Chelation works on the lead in the bloodstream, removing it via the kidneys and the urine. Chelation agents are not generally claimed to be able to remove lead directly from organs or bones.

I would certainly recommend blood lead testing as THE test of choice. No one should ever be suspected of having high lead levels because blood lead testing is available worldwide and no matter how much it costs it's worth it to KNOW if someone has a high blood lead level. Any doctor can order the test so please organise that as soon as possible and let me know the result so we can discuss next steps.

Has your father been working with lead? What are his suspected sources of lead? Can you remove them from him or him from them?

Once you have the blood lead result and preferably also iron status, the doctor is the best person to advise on the best treatment and treatment should only be undertaken under the supervision of a doctor. Please also see Iron Nutrition and Lead Toxicity if you need to help him improve his iron status.

I hope this helps. Please stay in touch.

Yours Sincerely

Elizabeth O'Brien