There are very sensitive indicator drops used for identifying ceramic glazes containing lead on antique porcelain.
There are also handheld scanners that cost more than a car. And yes, people in the community scan every imported toy and or food item they see to start the FDA ban process when necessary. Should buy local when you can anyway. =3
I am not a chemist, so take this with a pinch of salt: wouldn't lead chromate + sodium bicarbonate make lead carbonate, a white precipitate? Sodium bicarbonate is likely in your kitchen cupboard already.
Not a chemist either but lead oxide is actually more soluble in water than lead chromate, so a double replacement reaction won't favor lead chromate -> lead oxide.
Really? Lead test kits are $10 on amazon, and will include several dozen tests. The better kits will include paper to verify the tests still are working (short shelf life in the open.)
The sodium rhodizonate tests usually turn pink in the presence of traces of lead. These tests are intended for testing paints/ceramics, and may have false positives in the presence of zinc or copper etc.
Our local Griefers seem to have strong feelings about this information, but talk with your chemistry teacher if you want to understand the details about testing.
If a credible 3M brand test shows possible contamination, than consider sending a sample into a lab to figure out the details. =3
X-ray fluorescence detects elements based on their characteristic electromagnetic spectrum when irradiated with x-rays.
Not very much like a mass-spectrometer which creates a characteristic pattern of masses resulting from the test material as it is manipulated by the electron ionization or chemical ionization process. Where ions are detected across the atomic mass range of the particular spectrometer, forming a characteristic pattern or "spectrum" across that range.
Actually more jewelers and gold dealers than ever are using the x-ray guns professionally for bulk assay on an everyday basis. There are some handhelds which may be sensitive enough for trace analysis in food, but that requires a whole nother level of dedication beyond identification of metal objects, not just in technique and training but "laboratory" preparation as well.
The first obstacle would be convincing an owner of an instrument having capable specs, to embrace usage for things other than gold and silver assay. Then seriously pursue mastery of the instrument more so than ever to accomplish decent detection of low levels of lead and other metals like chromium, mercury, cadmium, etc.
[1] https://pubmed.ncbi.nlm.nih.gov/25214856/ ("Contaminated turmeric is a potential source of lead exposure for children in rural Bangladesh" / "Results: Lead concentrations in many turmeric samples were elevated, with lead concentrations as high as 483 ppm")
The higher it is, the less likely for challenges in detection, and/or interference from background.
>lead concentrations as high as 483 ppm
SSDD.
Shouldn't be that hard to detect at that level which is way above ppb. There are a number of reliable methods.
However if the Minimum Detectable Level for a particular test procedure was only 500 ppm or above, one of these samples would report just as clean as a sample having no lead whatsoever; < 500.
MDL's like this which vary among different test methods do need to be carefully compared to the toxicity levels being screened for.
That's another one of the confounding aspects to be aware of.
Depending on circumstances, I may or may not prefer a different calibration session for each of these two levels, even though they are both within the same order of magnitude.
Either way ideally I would be preparing NIST-traceable reference materials at the proper levels for comparison & confirmation. Not much differently than I would do for the benchtop models and the forklift models of x-ray units. And to really get down into the ppb levels that's when the ICP/mass-spec comes in handy, that's a benchtop unit itself, too big to fit on a regular desk though. However you don't really get the most out of the ICP without a huge cryogenic tank of liquid argon out back so you can "consume mass quantities" ;)
With a handheld x-ray unit, if you are only assaying gold & silver it may be fine to send it back for calibration once a year, if the pawn shops even do that. For food testing I would want more of a laboratory-style analytical procedure and calibration which is concurrent with materials being tested.
I agree that hand-held XRF guns should be able to detect such lead levels, and I believe that was in fact what the police used when they did the publicity stunt in the Bangladesh market. At any rate, it sounds like you know a lot more about the question than I do. I was only disputing pfdietz's comment, "The concentrations of lead being discussed here are as much as 1000 ppm or even higher."
Good call because results should be expectd to be all over the ball park, and I think even higher numbers could be found. But no amount of lead is supposed to be acceptable.
>sounds like you know a lot more about the question
SSDD says it all without explanation, but here's a little.
Until you've spent lots of time at the bench, it's not easy to understand why a 1000 and a 483 might just be the same sample tested in different labs.
Or even the same lab on different days.
If so that would look even more embarrassing when my arbitrary reporting convention < 500 is applied.
But it's actually not unheard of to get a positive and a negative on the same sample even with some of the most sophisticated equipment
Explaining the rest of the story could fill textbooks, but the operators wouldn't be reading them anyway :\
So that's the most important thing to know, besides the actual spectrums which are table stakes.
Too early to tell - usually they'll settle on something with a balance of those main values. If matrix is truly the new IRC then perhaps that, though it doesn't seem mature enough yet and it seems like it might be costly if one needs to host non-text content. Furries contain both highly technical people and also very low-tech artists so any platform that requires a lot of maintenance can be a non-starter. Signal seems like privacy over expression. Maybe this is the time that they'll make their own.
Most of that crowd that I interact with was already off Telegram to begin with, and (in some cases, begrudgingly) run their own Matrix instances.
I think if you interact with non-tech-users, Signal is the go-to; Matrix has way too many thorns for normal users to put up with in comparison to the alternatives.
As a furry: lmao no Matrix. Matrix does not get the job done at all. Profiles stored on the server you decided to join? Lots of silly design decisions.
Also the whole "furries make the internets go" is not really that true. There are certainly many of us in tech fields but going to meets/cons the average furry is not working in technology. The whole "suspiciously wealthy furry" thing just arose from the divide between tech worker and retail worker within the community. Gotta remember that most furries are like 16-25. Many tend to drop out or leave the community over 30-40 or so.
The Canadian Dental Care Plan (CDCP) was introduced to provide dental services to uninsured Canadians meeting specific criteria. Its rollout began in December 2023, starting with individuals aged 87 and above, and is set to expand to all eligible adults earning less than $90,000 annually by May 1, 2025.
This is actually a perfect example of how under-served dental needs have been. It was only passed via some interesting political wrangling and alliances. And it hasn’t been a smooth rollout with some dentists not getting on board. Starting with aged seniors is good from a compassion standpoint, but the emphasis should be on prevention at earlier ages.
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