Question: Anyone working on environmental lead exposure / poisoning?

Hi @read_holman, I added the tag question:lead to this great question in order to link this to some previous postings and a bit of discussion.

I've done a lot of lead testing. This was mostly by atomic absorption (AA), in an industrial situation.

The specs have changed. The lead levels are much lower than they used to be. A lot of the testing is now done by ICP. But, I have some experience with water testing, sample testing, incoming raw material testing ( the most common was clay), etc.

It can get nasty, with hydroflouric acid digestions. For water work, you usually don't have to deal with HF. But if you are dealing with lead in silicates, you do.

Excited that you might create a wiki page for "lead" ! You can create it by clicking the button on https://publiclab.org/tag/lead that says "Add one now".

While editing this new page, you can add this single line of text in the text area:

[questions:lead]

and it will automagically display all the questions asked so far about lead in a cute grid.

If you want to do more, you can add:

[notes:lead]

...all the research notes posted so far will display in another grid.

Voila!

@Ag8n I'd love to pick your brain about the technologies. I am familiar with the general trends, but only bc I've read about them, have worked with labs that have used them, and have spoken with an analytical chemist. AKA, I've never actually used them.

BUT I'd like to know them better. I'm also exploring what a low-cost / DIY testing kit might look like that doesn't involve fancy lab-based equipment like ICP-MS, AA, XRF (though that's more portable), and others...

I've thrown together this spreadsheet that has tech on the Y axis and sample-types + variables on the X. Do you mind taking a look at this and providing reactions? Certainly feel free to jump into that file, but even comments on whether I have the file structured appropriate and if I have all the main technologies listed would be helpful. I'll be chipping away at this over time...

Lead Testing Technologies Pros/Cons Matrix https://docs.google.com/spreadsheets/d/1zM4h274xcp3MzbXIz_VNsWXUSdFCcG38EgTOWQsz7t8/edit?usp=sharing

And for a bit more background... Here's a writeup of this effort I'm working on: https://publiclab.org/wiki/the-lead-data-collaborative-overview

I'd be happy to help. Give me some time to look it over.

I've worked extensively with EDXRF, but mostly the desktop (read R&D) variety. Only a little with the handheld units. Did a lot of AA work. Again, only a minor amount of ICP.

Did a lot of the USP tests for lead and heavy metals, but those often use hydrogen sulfide or other not so nice reagents.

I took my own advice and created publiclab.org/lead, linking to the Lead Data Collaborative at the top

Read- ICP-MS is the premier method.no doubt. But you pay for it. I'm second place is ICP-OES (ICP-optical emission spectrometry). Pretty much the same thing you call ICP-AES. Third place for me was GFAA (graphite furnace AA). You could get an adapter for an AA to convert it to GFAA. It still gave ppb resolution, but cost was between ICP and AA. Flame AA ( it can also do AE) is still popular. It is required for many methods.

The microwave methods weren't popular when I retired. Maybe they are now. As for XRF, there are two base methods, EDXRF and WDXRF. You want to go with EDXRF under most situations. WDXRF has many more regulatory requirements. More to follow...

As for difficulty: Worst is ICP- ME ICP-OES GFAA AS EDXRF Wet chemical Easiest

Many of the wet chemical methods can only detect heavy metals as lead. They usually detect this as the sulfide and produce a dark or black color. These often use hydrogen sulfide and can be dangerous. Other color methods are out there, though.

To give you an idea of what you are dealing with, let's look at flame AA. It takes the solution you are analyzing, mixed it with acetylene and air, and sends the mixture through a lot torch. The torch has a beam of light bedding through it from a hollow cathode lamp.

The air and acetylene is mixed before the flame, so if anything should happen to cause flashback, you get a big bang ( and other bad effects). Now imagine if you are analyzing gasoline for any lead. Sometimes the results were very nasty. .

As for what method can do soil, paint, water, etc. Edxrf has a big problem with water. Water absorbs xrays. You can get around this by evaporating the water, if you want. It's advantage is in paint and dust analysis. Lead shows up well in by edxrf. I was analyzing soot dust from a natural gas heated plant and found some strange elements (radioactive ones from natural gas).

One the other hand, for most environmental work, ICP-MS , is a much better way to go. It is just much more expensive and takes extensive training.

As for what method can do soil, paint, water, etc. Edxrf has a big problem with water. Water absorbs xrays. You can get around this by evaporating the water, if you want. It's advantage is in paint and dust analysis. Lead shows up well in by edxrf. I was analyzing soot dust from a natural gas heated plant and found some strange elements (radioactive ones from natural gas).

One the other hand, for most environmental work, ICP-MS , is a much better way to go. It is just much more expensive and takes extensive training.

Thanks @Ag8n - Really appreciate the time you spent typing all of this out. I'm going to try to convert your comments into the spreadsheet format, in a likely oversimplified format that gets the main points across to a less technical audience. Again: huge thanks!