Would you use a pair of binoculars to accurately count all the stars in our galaxy? How about using a magnifying glass to look for a virus?
You’d select a telescope for the first task and a high powered microscope for the second. You’d use those binoculars to spot birds on a nature hike.
In any measuring task – especially an important one – the appropriate tool for the job must be used. That is not happening today with the Portland Public Schools system lead crisis, and as a result the public is being misled.
What’s not being said (and then is causing what is being said to be misunderstood or misinterpreted by both the media and the public at large) is that the testing methodologies being subsidized by the Portland School District (in conjunction with funding from the Portland Water Bureau) and implemented by the Multnomah County Health Department for blood lead testing of children (and teachers) who attend Portland Public Schools are not sufficiently sensitive to detect the blood lead levels that would be expected to result from long term, chronic lead exposure due to daily intake of water with unsafe levels of lead in it.
The limit of detection of the testing methodologies in question is 3.3 micrograms of lead per deciliter of blood (or higher). This means these testing methodologies will simply not detect the presence of lead below the 3.3 threshold. This does not mean these methods are not valuable screening tools with useful applications – they are; they are just not the right tool for the task at hand, considering the levels of lead one could expect to find as a result of chronic low-level lead exposure from a daily-used water source.
Long-term, significant negative health impacts in both children and adults have been well-documented with blood lead levels as low as 2.0—(and indeed, with women of childbearing age blood lead levels all the way down to 0.5 and lower) well below the 3.3 limit of detection in these testing methodologies. Accordingly it is simply irresponsible for the County to draw any conclusion about whether or not anyone has any impacts from their PPS water exposure (or City of Portland water exposure in general) on the basis of results obtained using these testing methodologies alone.
As the facts stated here are well-known and well-documented (both the limit of detection and the impacts of blood lead levels far below this limit of detection) it almost seems as if the County, Water Bureau and School District intentionally chose the methods of detection they are using in order to (on paper – and in the press) absolve the School District and Water Bureau of responsibility for exposing (and potentially poisoning) the thousands of children who attend school at these toxic facilities. [And no, in case you’re wondering, this does not constitute speculation, hyperbole, nor hysterical exaggeration—just ask any of the top research scientists in the field.]
Additionally, taking into account the 30 to 45 day “half-life” of lead in blood (especially when the victim is removed from the source of exposure), even if a child had initially had a blood lead level of 4 or 5 or 6 micrograms per deciliter as a result of ongoing exposure from drinking water at school – the mere act of testing them (with these methodologies) 30 days or longer after school has ended (and after the schools have closed off access to their fountains) also seems like a calculated way to ensure that these children will not test positive with the testing methodologies being used—as by the time they are tested, that 4, 5 or 6 (which all would be noted as “concerning” to “elevated“) would normally be expected to have long-since dropped to 2, 2.5 or 3 – well below the limit of detection of these particular testing methodologies.
Finally, what about the children who are already being exposed at home? Their body burden of lead is definitely being increased by the chronic exposure to lead in water at school, and any efforts to dismiss those cases by concluding that those children’s levels were the result of “only being poisoned at home” is simply ridiculous and actually verging on scandalous. If a school-age child might have registered as having a blood lead level of 3.1 or 3.2 (below the level of detection of the testing instrumentation being used by the County) as a result of home exposure, it would be reasonably possible – quite likely, in fact – that their school exposure (in combination with their home exposure) pushed them over the limit of detection… to a 5.1 or a 6.0 for example. For the county to make public statements dismissing the potential contribution of the child’s chronic school exposure to lead in those cases is irresponsible – and practically criminal, especially taking into account the extensive knowledge of the nuances of the issue (and testing methodologies and their meanings) held by the people in positions of responsibility with the County.
What’s the answer then?
1) Don’t use children and teachers as “canaries in the coal mine.” A person should not have to be sick or symptomatic (or even test positive for lead) before they are entitled to be protected from environmental toxicity from a daily exposure.
2) We need to hold our public agencies accountable and insist that they use accurate language in their public statements on the issue. The ostensibly “negative” test results to date (lack of results testing over 3.3) are not – in this context – indicative of anything—and specifically not indicative of any range of perceived “fact” that might lead anyone educated in this issue to publicly state (or even imply) that there is no evidence that children (and teachers) have been exposed to (or poisoned by) harmful levels of lead as a result of this chronic exposure from water used daily. Of course there is “no evidence”—they are not using the right tool for the job. Use the right tool at the appropriate time, and we will undoubtedly see plenty of evidence!
3) The responsible action of the County and the School District in this situation (and with the specific knowledge that they have) would not have been to fund blood lead testing using these methodologies, but to insist on using the right tool for the job: the more conservative blood lead level testing using a venous draw with the samples analyzed in a lab or hospital – where the limit of detection is at least 1.0 (or even 0.1) and the margin of error for these tests is 10%, as opposed to 3 or 4 blood lead level points.
4) For any skeptical bureaucrats out there, my own children (who have a history of lead exposure) last had their blood tested at NW Primary Care in Sellwood, and their most recent tests showed blood lead level results of 0.4 and 0.8… so it is possible to find lower-limit-of-detection testing locally—in fact, we have multiple Portland, Oregon labs capable of that detection limit. [My children have also gotten accurate/lower-threshold results from the lab at Providence and the lab at OHSU/ Doernbecher—although you may need to ask in advance for the most specific test with the lowest limit of detection.]
Now go test your babies and please take anything said by any public entity, especially a public entity that has something at stake in absolving itself of responsibility – or in “not creating panic” – with a big, fat grain of salt!
Thanks for reading. For a more information on this issue, with more details and links, please peruse our website, LeadSafeAmerica.org.
Most important: read my favorite article on the subject of low-level lead exposure and the impact on children (and check out all of the scientific references at the end of the article.) Here also is an article about the impact of even lower levels (as low as a 0.5 or lower) on pregnant women (are we thinking about our teachers?)
Founder, Lead Safe America