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How To NOT Use A LeadCheck Swab

LeadCheckIt has come to my attention that some folks may not be using the 3M/LeadCheck swabs properly.

If you read the instructions it’s pretty straightforward, but I know—as an aging 44-year-old who does not yet have prescription glasses—that it can be annoying to read an entire sheet of tiny print when you just want to quickly get something done (like test something for lead)!  You really do need to read the instructions though—as failure to understand and rigorously follow the simple but critical intended procedure carries with it the dangerous potential for “false negative” readings,

There is no such thing really as a “false positive” reading with one of these actually… IF the swab turns pink or red – there IS lead present (with a low-threshold of 600 ppm lead – even below 600 ppm lead the swab may turn very light pink, but not always.)

However, consider the following (which has has actually happened):

Someone has NOT read the instructions and they think they’re supposed to rub the swab on the item as the first step of the test and (as it remains yellow/orange if there is no lead) they erroneously think that they are then supposed to…
touch the swab used on the item to one of the dots on the included reference card after testing the item in question.

This is NOT how that card is intended to be used.

This card is included for the instance where, following a negative reading (meaning the swab tip itself stays yellow/orange – does not turn pink), someone is doubtful and wishes to conclusively prove that the reagent in the swab is activated (properly mixed) and that the swab “works.”

In using the card with the swab – that swab will be “sacrificed” (once a swab is pink – it can’t be used to test anything else!), but using the card will settle the question of whether the swab was working or not. By following the steps below (steps 3, 4 and 5 specifically) you can assure yourself that the solution was mixed properly without using the card. Another way to use the card without sacrificing the swab would be to drip a small drop of the yellow solution from the swab to the card without the swab touching the card.  The dot on the card should then turn pink (and the swab, since it has not touched the card – would not turn color.)

Another thing that may be seen as a “false positive” (which really isn’t) is if someone tests something that is painted red and the red paint is lead-free, but some red pigment rubs off onto the swab. In my experience the color red of the paint never exactly mimics the pink of the positive test – and if one is careful in seeing color distinctions, that can also not be misinterpreted as a “false positive.”

There are also several good videos on YouTube that show the usage of the swabs and I encourage you to check them out. (We are working on our own video as well.)

First and foremost you MUST understand this:


The swabs work REALLY WELL for testing paint and painted items – their intended use, and reports that they are “ineffective” or give false readings are NOT TRUE – if they are used correctly.

Any product or item out in the world can be used incorrectly of course – you can use a bowl as a hat for example, and it may fall off your head (and not work well for the purpose of being a hat) but that doesn’t mean the bowl doesn’t work as a bowl – right?

So PLEASE understand the limits of this great testing technology, and use these swab kits for PAINT and PAINTED items.  They work for some other items as well and we will get into that in more detail later.

In general – in MOST cases – they DO NOT WORK on (and are not intended for use on):

  • jewelry
  • crystal
  • pottery
  • ceramics
  • dishes
  • cookware
  • crock-pots

This is because THEY USE A CHEMICAL REAGENT TECHNOLOGY—THAT WAS NOT INTENDED, DESIGNED OR FORMULATED FOR THESE USES. To discover lead embedded within a material and/or in a matrix of other materials (metals, ceramic compounds or otherwise), one needs a completely different kind of tool—a sophisticated instrument that can peer into molecular structure and read the item’s elemental make-up—called an X-Ray Fluorescence spectrometer (an XRF)!

I use a Niton XRF for the testing of dishes and cookware and ceramics that I do, and that is the ONLY tool (an XRF) that can give you quantifiable specific levels of lead. XRF instruments range in price from $10,000 to $40,000…. and I really LOVE my state-of-the-art instrument I have been given access to by Niton!

*  *  *

Here’s where it gets a little tricky…

SOMETIMES a LeadCheck Swab WILL be able to “find” (react to) lead on a piece of  metal or a piece of pottery or a crystal item!

If any of these items do test positive with a swab that is generally an exception – not the rule, and in such an instance you should assume they are VERY HIGH in bio-available lead on the surface of the item and they should not be used – starting immediately!  That does NOT MEAN that a similar item that tests NEGATIVE with a swab is NOT very high in bio-available lead, it may be… but again, the swabs were only developed for testing paint.

One example of this potentially confusing area is leaded crystal. I once tried a swab test on a leaded crystal goblet that I knew – from XRF analysis – to be upwards of 300,000 ppm lead. It did not test positive with a swab kit; as I expected—but that certainly does not mean it was safe, that does not mean is not leaching into the beverages contained in it. This goblet likely IS leaching lead in beverages and this has been studied and proven to be the case… but it is NOT a painted item and therefore the kit was not intended to test this sort of item.

I will be continuing writing on this post later – but I wanted to get at least some of this information out there right away.

While Lead Safe America Foundation has a strict policy of not specifically endorsing products, I personally think the LeadCheck swabs are a GREAT screening tool for consumers ESPECIALLY when the instructions are read and they are USED PROPERLY. Again, please watch videos to make sure you are using them properly if you do not have time to read the instructions (or if you have impaired eyesight like so many of us.)  I will post some video links here shortly too.

As I said, one other thing I think some folks MAY be doing by accident is using the verification card improperly. To reiterate:  THE VERIFICATION CARD contained in the swab kit (a small cardboard card with little circles on it) should not be used to “confirm or deny” that an item is positive. If you test an item and it is negative (the swab is still yellowish/orange) and then you go and rub that same swab on the verification card IT WILL ALWAYS TURN PINK!  That is because there is a very small amount of lead in the verification dot on the CARD, not because there is bioavailable lead in the surface of the item you just tested.

Thanks for reading.

More shortly.

Tamara Rubin
Mother of Lead Poisoned Children
Executive Director
Lead Safe America
Portland, Oregon
July 18, 2014

Simple instructions for using LeadCheck swab kits:

  1. Open the box… & READ THE INSTRUCTIONS (Pretty Please!)
  2. Set ALL THE PAPERS aside (including the verification card that has a bunch of circles on it.)
  3. Pull the paper sleeve back from the tube
  4. Confirm that one chamber has a gray powder and the other chamber has a clear liquid (sometimes/rarely the liquid tube has been cracked and there is no liquid left – if you purchased the item and this is the case, return it for a replacement.)
  5. Slip the paper tube back on
  6. Follow the Instructions…
  7. There are two spots on the paper tube that say “Crush Here.” When you do this (Crush the tube) you are crushing the powdered chamber and the liquid chamber of the vial within the plastic tube that is in the paper sleeve.
  8. Once both chambers are crushed – shake the swab gently to make sure the powder and liquid are well mixed
  9. Squeeze the tube gently while applying to the surface you are testing
  10. A small amount of yellowish/orange liquid will come out of the end on to the surface, rub that around with the white end (the cotton tip) of the swab
  11. If the swab turns pink (any range of pink) there is available lead in the item or surface you are testing.  The brighter pink, the more lead.
  12. If the swab stays yellow or orangish… there is no lead available on the surface of that item.
  13. Period.  The end.  Thanks for reading.


8 Responses to How To NOT Use A LeadCheck Swab

  1. Rick Byers July 18, 2014 at 6:31 pm #

    From the title of this article, I expected you to review and clarify any questionable instructions supplied with the kit. While I’ve never had any such problems personally, I think the title is misleading. I guess I misunderstood it or expected more from a leader in the cause. Keep up the good work – Rick

    • Tamara July 18, 2014 at 8:39 pm #

      Thanks Rick, we’re still working on this post and published a draft so that some information would be out there quickly (in response to some suspected misuse of the kits by followers of our Facebook page.) It should be final with full instructions very soon.

  2. Crystal July 30, 2014 at 6:43 pm #

    I thought this may be great info to hand out with test kits @my event. If we could get the most important points on 1 page. Thoughts?

    • Tamara July 30, 2014 at 9:56 pm #

      The instructions are pretty solid – plus we have our Simple Solutions cards that we’ll be sending you (You’ll need to organize an advance “stapling party” (before the event) to staple the cards to each of the kits) – once you get those cards in the mail from me, let me know if they are not enough. K?!

  3. dylan November 29, 2014 at 1:53 am #

    Hi there, one thing I am trying to figure out — can the kit be used to test liquids? So if I have a suspected lead crystal container, can I put alcohol or vinegar in it and test THAT for lead…rather than the container itself?

  4. Ashley August 31, 2015 at 4:19 pm #

    If the confirmation cards contain lead, is there a risk of contaminating other surfaces with it when handling the contents of the package?

  5. Christine May 23, 2016 at 3:40 pm #

    A question….. My test came back as negative, with the swab remaining yellow. However when I walked by the spot I tested about 20 minutes later, there was a hint of pink around edges? What do you think that would indicate?

  6. Abigail June 9, 2016 at 7:01 am #

    Do these tests work for porcelain bathtubs (of the clawfoot variety?) I am very concerned about the potential for lead in our clawfoot tub–but two tests came back negaative. Should I do further testing on this tub, or continue to use it as it appears safe according to these test swabs.

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