I’ve mentioned XRF before and provided pointers to information on what it was and what it meant for lead exposure monitoring. XRF is a true game-changer for lead exposure monitoring because it can measure how much lead you’ve absorbed in your bones (95% of body lead). Nothing short of a bone biopsy or tissue analysis at autopsy can achieve that, and XRF does it without poking any holes in you.

I’ve already talked about XRF, so why am I bringing up again?

The Department of Climate Change, Energy. the Environment and Water has a lot of information on lead, but the one that caught my attention was on auto paints (https://www.dcceew.gov.au/environment/protection/chemicals-management/lead/lead-in-auto-paints).

I found out that auto paints still contain lead, up to 20% and many painters, repairers and car restoration specialists actually realise that lead is dangerous. That’s kind of refreshing compared to mining WHS don’t you think?

The only way you can find out how much lead is there is by chemical analysis, or XRF. If you’re a painter in Melbourne or Perth and you want to use an XRF, you can hire one. That’s right, if you’re working with lead paint, you can determine, non-destructively, the lead content of the paint.

I’d better mention that the reason they use lead paint is it’s allegedly the only way to match the red, orange and yellow colours used in old cars (and old anything else). Did I tell you the story about the old bus in a paddock with a bunch of cows. The farmer (and vet) couldn’t figure out why they were so sickly, until he spotted on of his cows licking the bus. When they got rid of the old bus, they resolved the problem of sickly cattle.

There’s a lady in the US, Tamara Rubin, runs a site called LeadSafetyMomma (https://tamararubin.com) where she has measured the lead content of just about everything with her own portable XRF. Some of the results are kind of scary. Check them out. You might not want some of your old oven dishes.

If you had access to a portable XRF, you could measure the lead content of just about anything, like the dust in your house, the dirt kids are playing in or whatever. A second-hand XRF will set you back anything up to $5000, but if was available in the community, think what it would mean in terms of minimizing lead exposure and finding out what was dangerous.

When I suggested XRF with calibration etc thrown in to Glencore, my suggestion was dismissed with two reasons offered, (1) Glencore didn’t have one and (2) it was risky for Glencore workers because of the radiation dose.

The chances of Glencore NOT having a portable XRF spectrometer in Australia are pretty darn slim, BUT I have to admit the model XRF that has been calibrated to measure bone lead is somewhat special. At least they didn’t say it was too expensive. The Victorian EPA has 4 portable XRF spectrometers after all.

The comment about the radiation dose is pretty weak as the whole body dose of a 2 minute XRF measurement is 1.5 uSV [micro Sievert] which is at the low end of what you get from a dental x-ray (1-8 uSv). I could also compare it to the radiation you’d receive from an hour in the sun, or probably less than you receive from the U235 or Pb210 in the lead ore dust that’s all around you. Let’s just say the risk, unless you’re being tested every day, which is ridiculous, is minimal.

Safe Work Austrlia also mentions XRF in the document “REVIEW OF HAZARDS AND HEALTH EFFECTS OF INORGANIC LEAD – IMPLICATIONS FOR WHS REGULATORY POLICY”

There’s a section headed Biomonitoring, and this is what it says:

PbB (Blood lead) is by far the most common and arguably most convenient exposure metric used by regulatory authorities, industry and researchers. This may however have arisen as a result of historical use. A number of alternatives have been suggested by the scientific community but have not found their way into the regulatory arena. These include lead measurements in a range of accessible biological fluids and tissues. Of these the procedure with the most promise for supplementing PbB information is measurement of bone lead by non-invasive X-Ray Fluorescence (XRF) techniques. It provides a good, perhaps better indication, of chronic past exposures and total body burden. Unfortunately since bone lead reflects chronic exposures it arguably may not be an ideal method in the workplace to identify ‘at risk’ persons (i.e. persons currently assimilating unacceptable levels of Pb from workplace exposures). Whether the technique has been adequately developed and validated as a routine monitoring tool is also arguable.

The document was written 5 years ago and while the reservations about using XRF as a monitoring tool were valid at the time, it is now 2024 and XRF has most certainly been developed into a solid, validated technology for estimating bone lead.

SWA do have a point however. XRF measures the amount of lead accumulated in the bone. It isn’t sensitive enough to measure the small increments of acute lead exposure. That’s something where PbB (or BLL) is still useful. But if you added an additional element, chelation, then the dynamic changes. If the administration of a chelation agent prevented the absorption (and accumulation) of an acute dose of lead, and XRF showed a stable or hopefully reducing bone lead level, you’d be infinitely better off than you are now where a high PbB or BLL just shows you’ve been exposed to lead, and pretty well nothing else.

It’s going to take an effort to introduce XRF as part of the biomonitoring process, BUT what a difference it would make.

In terms of community lead hazard awareness, XRF would be beyond brilliant. Talk to the city council because we know Glencore is probably not interested.