Above photos shows a small Marble King brand green-swirl “cat’s eye” marble (randomly positive for 175 ppm Lead) next to a large Marble King brand green-swirl “cat’s eye” shooter (randomly positive for 1375 ppm Lead). Please note the level of Lead is not dependent on the size of the marble. – Photos by Avi B. Rubin, age 14
Test results for these marbles were originally posted as part of a more detailed post – for a science project my son was doing – in March of 2019, link here.
Wait, what? I thought Marble King brand marbles were Lead-free!?
Did you ever buy any marbles from the Marble King brand because you had read their advertising and thought they were Lead-free? Surprise: most of their marbles (at least most of the colors that I have tested – which includes about 20 different colors from this brand) are not Lead-free! The amount of Lead [or other toxic heavy metals – including Cadmium or Antimony!] varies, depending on the color.
Relevant points on the timeline for this conversation:
- I first made it public that Marble King “Lead-free” marbles tested positive for Lead (using XRF technology for total Lead content testing) in January of 2017.
- The company recently [apparently some time between March of 2018 and June of 2019] changed their marketing materials and the language on their website to reflect their new understanding that their marbles are not, in fact Lead-free.
- More info about that on this post – including “before” screenshots from the Marble King website from January of 2017.
Below is a screenshot from the Marble King website from March 8, 2018. This was more than a year after Marble King’s lawyers “communicated” with me that they were aware of my findings of Lead in Marble King products. This communication was in the form of a conference call with the owners of Marble King in which their attorneys challenged my findings and asked me to retract my public statements (and in which I assured them that my findings were accurate, science-based and replicable.)
In the March 2018 screenshot below, you can see that in spite of their *new* understanding that there was Lead in their products, they were still marketing their products as Lead-free more than a full year later. This image is followed by a second screenshot, which is of their website currently – from February 2020 – showing that the “Lead Free” language has been removed from the “About our Products” section of their home page. (continue reading below the two images):
#FunFact (Oh the DRAMA!)
In February of 2019 I tried to purchase some marbles directly from the Marble King website. I used my son’s name (Alexander Rubin) hoping that it would not trigger any alarm bells for the company, but did use my e-mail address (#Doh!)
Shortly after I placed my order I received an e-mail stating that my order had been cancelled and refunded by the company! They apparently wouldn’t even let me buy any marbles for testing!
I then had one of my readers purchase the marbles (pictured in this post) and send them to me once she received them so I could test them and report the results here on the blog.
Marble King marbles are still being sold as Lead-free today:
In spite of the fact that the company is now aware that many Marble King products contain Lead, resellers are still selling marbles from this brand with the marketing materials (and specifically the language in the Amazon listings) claiming they are “Lead-free” (scroll down to the bottom of this post to see the 9 images below of screenshots taken tonight – at the time of publishing this post – 2/10/2020 – listing Marble King marbles as “Lead free” for sale on Amazon.)
I have not tested all of the marble colors listed in the Amazon advertisements (screenshots) below (that are allegedly Lead-free, per these advertisements), but have tested about twenty different colors from this brand. The only one I found so far to be consistently Lead-free was the transparent clear. I will try to do more testing and reporting of current offerings from this brand this year (2020).
Overview of Lead readings by color
(see additional posts for more info)
- Small Transparent Clear: Non-Detect for Lead
- Small Orange Swirl: 92 +/- 11 ppm Lead
- Small Green Swirl: 175 +/- 15 ppm Lead
- Small White Swirl: 36 +/- 12 ppm Lead
- Small Blue Swirl: 123 +/- 15 ppm Lead
- Small Yellow Swirl: 152 +/- 17 ppm Lead
- Small Transparent Brown: 46 +/- 16 ppm Lead
- Small Transparent Green: 323 +/- 24 ppm Lead
- Small Transparent Blue: 27 +/- 10 ppm Lead
Continue reading below the image!
Below is the full XRF test result set for the large green Marble King green shooter (cat eyes style marble) pictured here. The marbles pictured in this post were purchased new in early-2019. [Continue reading below the image.]
Green Swirl Marble – Large (pictured above):
- Lead (Pb): 1,375 +/- 51 ppm
- Cadmium (Cd): 18 +/- 7 ppm
- Barium (Ba): 393 +/- 55 ppm
- Antimony (Sb): 3,437 +/- 110 ppm
- Tin (Sn): 193 +/- 17 ppm
- Zinc (Zn): 278 +/- 34 ppm
- Copper (Cu): 145 +/- 38 ppm
- Iron (Fe): 467 +/- 134 ppm
- Vanadium (V): 129 +/- 25 ppm
- Titanium (Ti): 356 +/- 44 ppm
- Indium (In): 57 +/- 12 ppm
How and why are the highlighted metals (in red, above) toxic?
Lead is a potent neurotoxin (considered unsafe and illegal in children’s items at levels of 100 ppm and above); Cadmium is a known carcinogen, considered unsafe at levels of 40 ppm and above* [so this level of Cadmium would not be considered unsafe (to the user)]; Antimony is not currently considered unsafe in glass consumer goods intended for use by humans, but has been studied and shown to cause cancer in rats.
*Washington (State) regulatory statute
Important points to note regarding these findings:
- A Niton XL3T XRF instrument was used for this testing.
- All testing was done in “Consumer Goods” mode.
- Each XRF test was done for a minimum of 60 seconds and repeated multiple times to confirm the results.
- The results are replicable and accurate.
- The instrument was freshly calibrated prior to the tests being done.
- The tests were done with a fully charged battery in the instrument.
- The marbles tested were newly purchased and had not been used or played with (limiting the potential for allegations of possible external sources of contaminants.)
- The marbles were tested against a background that was tested first and confirmed not to test positive for any metals (an unpainted natural wood surface.)
- Metals not detected in consumer goods mode are not listed.
- Note: on swirl marbles when the colored part of the marble was closer to the XRF scope (turned towards vs. turned away) many of the metals readings were higher (demonstrating that the metals are in the colors more so than in the clear elements.)
Takeaway: Why is this a problem?
Will this much Lead in a marble poison my child?
- Is it is unclear as to whether any of this could ever pose any sort of risk to the user (child) when used as intended; the larger issue is the continued practice of adding highly toxic heavy metals as colorants in glass — which poses definite exposure risks to workers, as well as releasing toxic pollutants into our planet’s air, water, and soil as a result of the manufacturing process.
- Specifically also at issue here is the concern for false advertising claims (historically) made by this company (Marble King). In addition to environmentally-conscious consumers, many families with Lead-poisoned children have chosen this brand BECAUSE of their “Lead-free” advertising claims [and have continued to choose this brand, not realizing their advertising claims have changed]. To my knowledge, no public notice or formal announcement was made by the company acknowledging their products have Lead, so the public is generally still in the dark on this, despite the fact that the specific language on their website has (quietly) changed.
- Finally, I do have some concern for Lead and other toxicants found in marbles – especially with accidental ingestion by small children, BUT I believe the potential for toxicant exposure from a swallowed marble to possibly poison a child has not been sufficiently studied. That said, with glass marbles and beads that test positive at 5,000 or 10,000 ppm Lead and above, I definitely would have a specific concern for potential poisoning with ingestion.
- I have actually tested small glass beads (marble-like beads) that were as high as / higher than 300,000 ppm Lead, and I will be posting more about those shortly. Marbles and beads that fall in this category (essentially Leaded crystal) are especially concerning – and the problem is that there is really no means for a consumer to know how high the Lead – or other metallic toxicant – content in any particular marble is.
- With these particular Marble King brand marbles (pictured on this post), given the level of the Lead found and the fact that the Lead appears to be solely in the colorants — and the colorants (at least in the “Cat eye” models) seem to be on the marbles’ interior (and then possibly surrounded by Lead-free clear glass), it is my educated guess that these specific Marble King marbles are less likely to cause a potential poisoning concern with ingestion.
- HOWEVER please note: I often see iridescent or otherwise painted marbles in which the Lead is specifically in the surface coating [here is an example, link] and in my (educated) opinion, marbles with potentially Leaded exterior coatings (even with Lead at the same Levels as has been found in the Marble King brand products tested here) present a much more significant potential poisoning concern (with ingestion and handling by young children.)
With all of the above considerations taken into account, I stand 100% behind the belief that there should be no Lead in marbles sold at all — as the risk for young children is too great, and there are too many uncertainties. Accordingly, with my own children we stopped having marbles in the house until they were beyond the phase of putting things in their mouths, and when we finally did add marbles in to the mix (primarily for Chinese Checkers and marble track games) we chose marbles without iridescent coatings and without exterior painted decorative elements.
Some additional reading that may be of interest:
- More posts about my interaction with this brand, Marble King.
- A post discussing the testing methodologies used on this blog.
- More posts I have written about glass items I have tested.
- More posts I have written about green glass items I have tested.
As always thank you for reading and for sharing my posts.
Please let me know if you have any questions.