A definition of lead poisoning is not straight forward.  Some people (or policy makers) would have you believe a lead poisoned child is only a child under the age of 6 that currently  has a blood lead level of 10 micrograms per deciliter or higher.  The United States Federal threshold set by the Centers for Disease Control (CDC) is a BLL of 10. The CDC only measures children between the ages of 1 and 6 (and - as far as I can tell from the research I have done - does not count children under one year of age or 6 years old and older.)

    The fact that the CDC publicly states that “there is no safe level of lead in a child’s blood” seems to get lost in the passing on of this information to doctors, parents, childcare providers, etc.  They see the “BLL 10” as the definitive marker to determine if a child has been poisoned.   (Using the CDC’s public stance on the subject - neither of my children would count as a poisoned child.  Avi  - who had a BLL of 16 when he was first tested - was under the age of 1 (he was 8 months old) and A.J. (who had the most severe symptoms and is the reason we had Avi tested too) had a BLL below 10 micrograms per deciliter!)

    In spite of the Federal action level many States are lowering or have already lowered the threshold (at which a child is considered poisoned) to a BLL of 5 micrograms per deciliter. 

        In Oregon when my children were poisoned (in summer/fall of 2005), even though the Federal CDC threshold was BLL 10, the Oregon State threshold was set at BLL 15 - so a child was not considered poisoned (and not eligible for State Sponsored intervention efforts and funding) unless their BLL was 15 or higher (50% higher than the federal threshold.)
    Advocates like myself (perhaps a bit on the extreme other end of the spectrum) want the general definition of a lead poisoned child to be understood as any child (of any age) who has ever tested positive for lead with a blood lead level of 2 micrograms per deciliter or higher.  Lead leaves a permanent mark on the child’s brain and they continue to be effected by the poison long after their blood lead level has gone down. Lead in the blood only shows lead present from a recent exposure.  In fact many symptoms of childhood lead poisoning don’t even show up until long after the initial exposure (since they are primarily seen as behavioral issues and learning disabilities which take time to surface (if the child was poisoned as an infant) and time to be diagnosed (especially if the child is not yet in an educational/ school setting when they are poisoned.))

    The natural level of lead in pre-industrial humans has been found to be less than .016 micrograms per deciliter - so a BLL of 5 (for example) represents a lead burden on a child of more than 300 times the natural background level of a potent neuro-toxin (see this link for discussion of low levels.)
    Advocates  like myself would like to see the Federal (CDC) action level set at BLL 2 (with any child that has a BLL of 2 or higher seen as exposed and an inquiry done / and resources made available to the family of the child to determine the source of exposure to the child and limit/ prevent future/ continued or increased exposure) only because many labs will not test with an accuracy that shows levels below BLL 2 (they give their lowest reading at “less than 2” and consider that an effective zero.)


    There is a also whole spectrum of opinions in between those two extremes.

    Of course lead poisoning is not limited to children and the definition for adult lead poisoning also varies.  Opinions about this also have as wide a range as opinions about childhood lead poisoning. When I was pregnant and had a blood test for lead I was told that anything under a BLL 22 was okay (this was in the winter of 2008 in Portland, Oregon).  There is a reference somewhere (very outdated) that midwives have for maternal pregnancy that tells them a mother is okay with a blood lead level of anything below BLL 22.  However research also clearly shows that the fetus/newborn has a BLL of 80 to 100% of the mother’s BLL.  So if a pregnant mother’s BLL is 20 (and considered “okay” by some misguided health practitioners) her unborn child may have a BLL of somewhere between 16 and 20  - a BLL in that range for an unborn child is considered definitely poisoned by anyone’s standards today, so by what logic is a mother’s BLL of up to 22 okay?

    OSHA has standards for adults working in industries that expose them to toxins  - and (correct me if I am wrong) adult men are not considered poisoned in the course of work unless they have a BLL of 40 or higher.  Yet BLL’s much lower than that can cause all of the symptoms associated with lead poisoning.


    The reason advocates are pushing for lowering Federal action level for children is that there is no known safe level of lead in a child’s blood - no “reference dose.”  Adverse effects have been studied and observed in children with BLLs of 2, 3 and 4 - as well as higher levels of course.  Recent studies have also shown that the first 10 points of lead poisoning call also be the most damaging in terms of a child’s neurological development and long term resultant issues (learning disabilities, behavioral issues - etc.) with the higher points of lead poisoning (above 10) often resulting in more severe physically damaging symptoms.


Please - if you feel I have made any factual errors here or if you would like to contribute a resource for me to link to back up some of my statements, I would appreciate an e-mail!  Thank you.


Tamara

leadsafe@mac.com

 

© 2009. Tamara Rubin,  All Rights Reserved

Definition