Originally posted: January 7, 2017
Updated: November 19, 2020
I have written this post out of frustration for the rampant misinformation given to parents when they first get their children tested.
more on that.
Q. What is a normal BLL? How do I know if my child’s BLL is normal?
A. There is no normal level of Lead in a child’s blood.
The image above is my youngest son Charlie’s blood lead test result from October 30, 2014. In it the doctor checked a box and left just one comment “These lab results were normal.” We then got a new doctor (actually we went back to his old doctor who knew what she was talking about when it came to Lead!)
I am sharing my son’s test result with you as it is an example of is EXACTLY the kind of test result you DON’T WANT TO GET from your doctor. There is no value to a test result like this. Again, I reiterate – there is no level of lead in a child’s blood that is “normal.”
Get a Blood Lead Level NUMBER.
When you get your child tested your doctor should give you the results in the form of NUMBER. Common possible results might look like this (all measurements are in micrograms per deciliter if you are in the United States.)
You may get a “less than” reading.
In this case you may opt for for a second, more accurate follow up test. Possible “less than” readings generally look like one of the options below.
- “< 1” – read as “less than one microgram per deciliter”
- “< 2” – read as “less than two micrograms per deciliter”
- “< 3” – read as “less than three micrograms per deciliter”
- “< 3.3” – read as “less than three point three micrograms per deciliter”
- < 5 – – read as “less than five micrograms per deciliter”
By far the most common “less than” reading is “less than 3.3.” The reason this is so common is…
You may get an actual number reading.
It is preferable to get an actual number reading with the lowest possible level of detection available in your area. Actual number readings my own children have gotten have been the following numbers:
- 16.0 micrograms per deciliter
- 4.0 micrograms per deciliter
- 3.2 micrograms per deciliter
- 1.6 micrograms per deciliter.
- 0.8 micrograms per deciliter
- 0.4 micrograms per deciliter.
What you need to know / need to ask for
#1) If you don’t get a number ask for an exact number.
If at all possible you need to ask for (and know and have documented) the EXACT NUMBER of your child’s blood lead test result(s).
A test with no numerical value (and to some degree a test with a value that is only “less than” such as “less than 3” or “less than 5”) is not particularly helpful in the long term (or the short term for that matter.)*
#2) Ask (in advance of your testing appointment) for the most accurate testing methodology: a venous draw.
If at all possible the best test (with potentially the most accurate results) will come from a venous draw at a lab, however not all labs are equal.
Ask your doctor in advance of your child’s test if they (or the lab they use) give results as an exact level (down to the lowest possible threshold of detection.) If they do not do that kind of test in your doctor’s lab you should ask the doctor to refer your child to have their blood lead tested in a lab that does give you an exact number.
My two youngest children’s last blood lead tests came up as a BLL 0.4 and a BLL 0.8. Results to this degree of accuracy are possible and important to get if you have the opportunity.
#3) Ask in advance of your testing appointment for the low threshold of detection of the testing at the lab where your sample will be analyzed.
#4) Ask in advance of your testing appointment for the margin of error the testing at the lab where your sample will be analyzed.
#5) Know your number!
Knowing the exact number helps you to make informed decisions for your child and also gives you a baseline that you can compare future tests to – so you know if the child’s level goes up or down. By knowing if your child’s blood lead level changes (with periodic testing – every 6 months or so in infancy and toddlerhood and then at least annually through the teen years) you can pinpoint the source of their exposure if in the future (by being able to pinpoint the time-frame of exposure) they test positive at a higher level.
Q. When should a child first get tested?
A. Earlier than doctors are currently recommending!
I always recommend that a child first get tested at 6 or 7 months (before they start to crawl), and then again 4 to 6 months after that first test (or as soon after they begin to crawl as you are comfortable testing.) This way you can find out a base level for the child at a time when they should not have had any environmental exposure (pre-crawling) and catch any post-crawling exposure before it is prolonged and potentially more damaging.
Of course in order to PREVENT exposure in the first place it is best to test the house and floors first (using dust-wipe sample testing, prior to a child inhabiting a home if possible, and definitely prior to crawling) so you can know the potential risk to the child – but I understand that is not always possible and still encourage the blood lead testing scenario above regardless of whether or not the house has been tested (as exposure can come from grandma’s house or daycare and other potential sources!) My friends at CertifiedKit.com offer a DIY dust-wipe testing kit or you can have a home inspector come do it for you.
#5) Understand the federal standards so you can clearly explain to your child’s doctor why they are misinformed.
#6) Reminder: Get a baseline Blood Lead Level test as early as possible
I wish my children had had a baseline from an earlier test to compare to their test results at the time they were poisoned (that would have helped us assign liability to the contractor among other potential benefits!), however in the 9 years of my experience as a parent prior to my children’s poisoning it was NEVER ONCE suggested by their doctors that they be tested for lead.
As always, please let me know if you have any questions.
Mother of Lead Poisoned Children
Unexpected Lead Expert
*The only exception in which a test that results in a “less than” reading – should still be considered a useful screening tool is if you have the opportunity to get a finger-prick test at (for example) a free clinic, which is quick (it usually just takes about 3 minutes to get a result- using a machine called a LeadCare2) and will give you a low threshold blood lead level of “less than 3.3” due to the restrictions of the instrument (which is intended for using in the field.) If you get a result like this you can always ask your doctor for a follow up test/to get a more specific result.