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Specialty Chemistry Forums => Citizen Chemist => Topic started by: beebug on November 23, 2020, 09:37:55 AM

Title: Mercury leaching?
Post by: beebug on November 23, 2020, 09:37:55 AM
Hello. I hope I’m in the right place here. My apologies ahead of time if I’m not. I’m no scientist! Just a really worried mom.

You see, I have an old harmonica from the 70s or 80s that my child was playing with. She’s 2. I was doing some reading online about the materials used to make this instrument.

I came across a website by Tamara Rubin, who used a XRF instrument to see if there were any heavy metals in some of these similar harmonicas.

She found the edges to contain about 450 ppm mercury and 150 ppm arsenic.

This seems extremely high.

My child would put this instrument in her mouth for a few seconds here and there, and would carry it around.

How does this work? Can the mercury and arsenic leach into her body when she puts it in her mouth or even carries it?

I feel like I’ve poisoned my child. I’m very confused. As I have said, I’m not chemist or scientist, but that much mercury????

Am I worried for nothing and getting this all wrong? Help???!
Title: Re: Mercury leaching?
Post by: Borek on November 23, 2020, 11:10:02 AM
1. I haven't checked the As, but the number for mercury doesn't look really high to me, as it is comparable with mercury content reported for other common materials we are surrounded with (like wood). Mercury in trace amounts is, was and will be everywhere (same can be said about almost every element).

2. It is not the content that matters, but amount that can be freed and consumed. Total amount of mercury in the harmonica is - in the worst case - orders of magnitude lower than the lethal amounts. Plus, even if it leaches, it does it very slowly, further reducing any risks.

3. Yes, traces of mercury and As can leach and get swallowed. As I wrote above, chance that these are in any way dangerous are close to zero. I wouldn't worry personally, but if it will make you feel better - just hide the harmonica.

4. Don't worry too much, it never helps :)
Title: Re: Mercury leaching?
Post by: Corribus on November 23, 2020, 11:15:26 AM
First and foremost, you can't trust a lot of the stuff you read online. What was the source of this information? Do you have a link.

Second, a lot of alloys contain trace mercury. Having contact with such a material does not necessarily mean oral exposure (ingestion), and oral exposure doesn't necessarily mean intestinal absorption, and intestinal absorption doesn't necessarily mean toxicity. A lot would depend on the the dose, the bioavailability, and the form of mercury. Elemental mercury, for example, is much less toxic than organomercury or ionic mercury, such as what you would be exposed to from fish.

Just for a bit of perspective: mercury has been used in dental fillings for years and continues to be used to this day because the risks are widely agreed by experts to be very low. And filings have a very high concentration of (freshly prepared) mercury compared to the 400ish ppb level in an alloy you have found reported. And volatility of the mercury in fillings and subsequent inhalation is probably a much worse hazard than ingestion. Volatility of the mercury in the alloy is probably almost zero.

So, my opinion is that you have nothing to worry about. Exposure if very brief, concentration of mercury is very small, and the toxicity of elemental mercury is actually pretty low as well. The benefits of your child learning to play an instrument far exceed any danger here :D
Title: Re: Mercury leaching?
Post by: beebug on November 23, 2020, 12:00:18 PM
Thank you so very much for the answers. What a great forum with knowledgeable people!

As a reference, the website I was looking at is linked just below. As you can see, I completely panicked and commented on the blog, even volunteering to send the lady the harmonica to test it! I of course, won’t be letting my child play with it anymore. She would carry it around in her hands, and only very briefly put it in her mouth!
Title: Re: Mercury leaching?
Post by: Corribus on November 23, 2020, 01:32:23 PM
One thing to keep in mind is that a number is just a number. There's no context provided on either how the measurement was made or on what the values are supposed to mean. We could certainly nitpick quite a bit at both of those problems and to my mind the endpoint would be that the numbers mean absolutely nothing until it can be demonstrated that the measurements were made by technically qualified personnel using a validated method fit for this specific purpose, and then the values examined by someone who can put them into proper toxicological context. Until then, I would personally not lose any sleep over it.

That said, I'm a parent, too, and understand the need to be cautious. My personal opinion is that no harm has been done but maybe it would put your mind at ease to find your child another toy to play with in the future ;).

Although, it's important for us to state that we do not offer actionable medical advice at this forum so if you feel you have a reason to be truly concerned, then you should always consult a medical professional in person.
Title: Re: Mercury leaching?
Post by: beebug on November 23, 2020, 03:34:48 PM
Absolutely. Thank you. I am not seeking medical advice, just trying to understand if there is a danger of heavy metal exposure to the point where it a health concern.

As a follow up question, would the same apply to lead?

I ended up contacting the company who made the harmonica, and they gave me an additional scare by indicating the instruments they made before a certain date contained lead in the brass parts (which my child happened to put into her mouth). This is what I was told:

“harmonicas which are produced before 1980 can have lead inside the brass material of the reed plates because of technical reasons (stamping the reed plates at that time). Of course the lead inside the brass is bound in and does not migrate out.”

Any comments? Do I now have to be worried about lead exposure? 🤦‍♀️
Title: Re: Mercury leaching?
Post by: Borek on November 23, 2020, 06:14:01 PM
Do I now have to be worried about lead exposure? 🤦‍♀️

Nope :)

More or less everything that was said about mercury and arsenic holds also for the lead. It actually holds also for every other element present.