Cleaning Leather With Oxalic Acid Crystals Or Lemon Juice

[drphil]

Hi Bard Skye

Mee too! All good points for sure!

*One of the reasons I started this subject up is because there are so many new folks joining every day…

I thought it would be good to bring up this subject again & let folks know about the

Oxalic Acid Crystals MSDS before they buy it….. and to also discuss the alternatives.

The Possibility for Health issues or someone's animals or kids getting into the hazardous chemicals – makes if an easy choice for me.

Thank you so much for your comments

As I have mentioned before, do not put too much stock in what the MSDS says. The MSDSs are designed to inform people about any, all, potential, possible, might happen, might never happen effects of chemicals. While it is true that oxalic acid is more reactive and worse for your health than other compounds used to clean leather. it should not be looked at as worse for your health than other chemicals without much more experience with the compound itself. What I am saying is that it depends more on what you are reacting with, what concentration you are using, and how safe you are working with the chemical (proper protective equipment etc.).

As far as oxalic acid behing hazardous, I would say yes. Is lemon juice hazardous? Yes in the right situation. Take a look at the MSDS for table salt. Hazardous? You bet! Check it out:

"Precautions:

Keep locked up.. Do not ingest. Do not breathe dust. Avoid contact with eyes. Wear suitable protective clothing. If ingested,

seek medical advice immediately and show the container or the label. Keep away from incompatibles such as oxidizing

agents, acids"

Now consider the MSDS for some of the primary ingredients of lemon juice that are good for cleaning leather. Ascorbic acid (vitamin C) and citiric acid. Let me know if those scare you a little. Check out acetic acid from the vinegar. How about phosphoric acid in Coke.

One should not think of a chemical as being hazardous just because they don't recognize it easily. Many people get the idea that just because something does not occur naturally that it is especially hazardous. This is no more true than the reverse. As I mentioned in previous posts, snake venom is a naturally occurring product, that doesn't make it safe for me.

On another note, oxalic acid does occur naturally and in products you might eat. Take Rhubarb and spinach for example. The thing is, the oxalic acid is not as concentrated there as the crystals you might buy. Of course you should making a dilute solution with those crystals anyhow when cleaning your leather.

The overarching conclusion is to use chemicals (anything made of atoms) carefully and safely. Consult the MSDS, consult a chemist, consult anyone with experience and follow their reasoning. Better safe than sorry. Do not dismiss something as being more hazardous/less hazardous just because of your preference for "organic" or common products. I am using the term "organic" here in the common consumer sense which is almost completely at odds with the chemical definition of organic.

I would venture to guess that there are many more hazardous chemicals that are in your house that kids and pets could get into as well. Be safe and use common sense.

I would probably use vinegar to clean my leather as well, although I have no experience with cleaning leather. Anyone have any experience using other acids? Perhaps hydrochloric, or acetylsalicylic acid. I am inclined to think that dissolving a couple of aspirin tablets (mostly acetylsalicylic acid) in water might yield good results. I am very curious to know what the results are.

Dilute 4 to 1, water to vinegar. Stubborn stains increase vinegar. Yes, it does need to be washed with clean water to neutralize the vinegar.

Make sure your leather has dried thoroughly before applying finishes and/or dye.

ferg

And, while we are speaking "chemically" here it should be noted that water will not neutralize the vinegar it will only dilute it. Not that it is that too important. :-) I assume you would still have a little vinegar smell like 'rooned leather?

[Ferg]

You are correct, simply washing an object with water does not completely neutralize the vinegar but it does indeed dilute it to the extent that it offers no detrimental effects. As I said in my previous post, "Allow the leather to dry completely before applying finishes or dyes."

I can find a thousand things in everyday life that could hinder a person's health. Unfortunately today, folks are so immunized against so many things that we ate when I was a kid. They would probably kill half the population now.

Use common sense folks. I like to think most Leather folks are at least a little smarter than the average Joe/Jerry.

ferg

As I have mentioned before, do not put too much stock in what the MSDS says. The MSDSs are designed to inform people about any, all, potential, possible, might happen, might never happen effects of chemicals. While it is true that oxalic acid is more reactive and worse for your health than other compounds used to clean leather. it should not be looked at as worse for your health than other chemicals without much more experience with the compound itself. What I am saying is that it depends more on what you are reacting with, what concentration you are using, and how safe you are working with the chemical (proper protective equipment etc.).

As far as oxalic acid behing hazardous, I would say yes. Is lemon juice hazardous? Yes in the right situation. Take a look at the MSDS for table salt. Hazardous? You bet! Check it out:

"Precautions:

Keep locked up.. Do not ingest. Do not breathe dust. Avoid contact with eyes. Wear suitable protective clothing. If ingested,

seek medical advice immediately and show the container or the label. Keep away from incompatibles such as oxidizing

agents, acids"

Now consider the MSDS for some of the primary ingredients of lemon juice that are good for cleaning leather. Ascorbic acid (vitamin C) and citiric acid. Let me know if those scare you a little. Check out acetic acid from the vinegar. How about phosphoric acid in Coke.

One should not think of a chemical as being hazardous just because they don't recognize it easily. Many people get the idea that just because something does not occur naturally that it is especially hazardous. This is no more true than the reverse. As I mentioned in previous posts, snake venom is a naturally occurring product, that doesn't make it safe for me.

On another note, oxalic acid does occur naturally and in products you might eat. Take Rhubarb and spinach for example. The thing is, the oxalic acid is not as concentrated there as the crystals you might buy. Of course you should making a dilute solution with those crystals anyhow when cleaning your leather.

The overarching conclusion is to use chemicals (anything made of atoms) carefully and safely. Consult the MSDS, consult a chemist, consult anyone with experience and follow their reasoning. Better safe than sorry. Do not dismiss something as being more hazardous/less hazardous just because of your preference for "organic" or common products. I am using the term "organic" here in the common consumer sense which is almost completely at odds with the chemical definition of organic.

I would venture to guess that there are many more hazardous chemicals that are in your house that kids and pets could get into as well. Be safe and use common sense.

I would probably use vinegar to clean my leather as well, although I have no experience with cleaning leather. Anyone have any experience using other acids? Perhaps hydrochloric, or acetylsalicylic acid. I am inclined to think that dissolving a couple of aspirin tablets (mostly acetylsalicylic acid) in water might yield good results. I am very curious to know what the results are.

And, while we are speaking "chemically" here it should be noted that water will not neutralize the vinegar it will only dilute it. Not that it is that too important. :-) I assume you would still have a little vinegar smell like 'rooned leather?

[oldtimer]

I would say that using contact cement is more hasardous to your health than using oxalic acid.

/ Knut

[WinterBear]

Just for comparison (from http://msds.chem.ox.ac.uk), the lowest published lethal dosage (LD_lo) in humans (men and women) and lethal dose 50% kill (LD₅₀) for rats for common household acids taken orally (as compared to inhalation or other methods or exposure) are:

-oxalic acid as oxalic acid dihydride: LD_lo of 600 mg/kg in humans for oral ingestion, and for rats, LD₅₀ 7,500 mg/kg for oral ingestion

-acetic acid = LD_lo 308 mg/kg in humans (no method of intake was given), and for rats, LD₅₀ of 3,310 mg/kg for oral ingestion

-boric acid = LD_lo of 200 mg/kg and also 429 mg/kg for oral ingestion in humans (woman and man, respectively), and for rats, LD₅₀ 2,660 mg/kg for oral ingestion

-acetylsalicylic acid (asprin) = LD_lo of 104 mg/kg and also ~ 400 mg/kg for oral ingestion in humans (child and man, respectively), and for rats, LD₅₀ 200 mg/kg for oral ingestion

-citric acid as citric acid monohydrate: no data given for humans, and for rats, LD₅₀ of 11,700 mg/kg for oral ingestion

So based on common concentration of these chemicals (excluding citric acid) for oral ingestion only and based on the lowest reported fatal dosage, the order of increasing toxicity for humans is: oxalic acid dihydride < acetic acid < boric acid < acetylsalicylic acid. For a 50% kill rate in rats, the order is farily similar: citric acid < oxalic acid dihydride < acetic acid < boric acid < acetylsalicylic acid.

All this means of course, that if you ingested a similar concentration of any these acids, the citric acid will generally be the least lethal and acetylsalicytic acid the most. It doesn't mean that they are "safe", but it doesn't mean they are automatically extremely dangerous either. It just means that you need to follow instructions carefully, take reasonable precautions against splashes, accidental ingestion, skin exposure, and inhalation, that you don't mix it with anything else (even another "safe" chemical or solution), and you clean everything up afterwards and dispose of it properly.

[cybertracy]

fyi: if you choose to go the oxalic route, an inexpensive, very common source is the product "Barkeeper's Friend" found in the cleanser aisle of most grocery stores. Its only ingredient is oxalic acid and it's generally used as a less abrasive alternative cleanser for copper and other soft metals. MSDS

[stanly]

Just for comparison (from http://msds.chem.ox.ac.uk), the lowest published lethal dosage (LD_lo) in humans (men and women) and lethal dose 50% kill (LD₅₀) for rats for common household acids taken orally (as compared to inhalation or other methods or exposure) are:

-oxalic acid as oxalic acid dihydride: LD_lo of 600 mg/kg in humans for oral ingestion, and for rats, LD₅₀ 7,500 mg/kg for oral ingestion

-acetic acid = LD_lo 308 mg/kg in humans (no method of intake was given), and for rats, LD₅₀ of 3,310 mg/kg for oral ingestion

-boric acid = LD_lo of 200 mg/kg and also 429 mg/kg for oral ingestion in humans (woman and man, respectively), and for rats, LD₅₀ 2,660 mg/kg for oral ingestion

-acetylsalicylic acid (asprin) = LD_lo of 104 mg/kg and also ~ 400 mg/kg for oral ingestion in humans (child and man, respectively), and for rats, LD₅₀ 200 mg/kg for oral ingestion

-citric acid as citric acid monohydrate: no data given for humans, and for rats, LD₅₀ of 11,700 mg/kg for oral ingestion

So based on common concentration of these chemicals (excluding citric acid) for oral ingestion only and based on the lowest reported fatal dosage, the order of increasing toxicity for humans is: oxalic acid dihydride < acetic acid < boric acid < acetylsalicylic acid. For a 50% kill rate in rats, the order is farily similar: citric acid < oxalic acid dihydride < acetic acid < boric acid < acetylsalicylic acid.

All this means of course, that if you ingested a similar concentration of any these acids, the citric acid will generally be the least lethal and acetylsalicytic acid the most. It doesn't mean that they are "safe", but it doesn't mean they are automatically extremely dangerous either. It just means that you need to follow instructions carefully, take reasonable precautions against splashes, accidental ingestion, skin exposure, and inhalation, that you don't mix it with anything else (even another "safe" chemical or solution), and you clean everything up afterwards and dispose of it properly.

oxalic acid also is used as deck bleach- found at building supply stores iin liquid form.

AND mostly what I'm getting from the above tables is .... Damn those rats are tough.

[WinterBear]

Pretty much. If it'll kill a rat, it's something that can kill a person.

[bentley]

Want your leather to look like copper patina? Clean with oxalic acid and dye with Fiebings light blue, not the look I was trying to achieve but there is some reaction with the acid I guess.

[Charliewz]

Thanks for the info Tracy, I have been going to try oxalic acid and now I will try Barkeepers friend, sounds good to me. Charlie

fyi: if you choose to go the oxalic route, an inexpensive, very common source is the product "Barkeeper's Friend" found in the cleanser aisle of most grocery stores. Its only ingredient is oxalic acid and it's generally used as a less abrasive alternative cleanser for copper and other soft metals. MSDS

[BondoBobCustomSaddles]

You are correct, simply washing an object with water does not completely neutralize the vinegar but it does indeed dilute it to the extent that it offers no detrimental effects. As I said in my previous post, "Allow the leather to dry completely before applying finishes or dyes."

I can find a thousand things in everyday life that could hinder a person's health. Unfortunately today, folks are so immunized against so many things that we ate when I was a kid. They would probably kill half the population now.

Use common sense folks. I like to think most Leather folks are at least a little smarter than the average Joe/Jerry.

ferg

Like Ferg, I have been using oxalic acid for years, probably between Ferg and I we have better than 100 years of experience with it, and no problems. Like Ferg says, "use common sense folks", and you will be fine, no need to reinvent the wheel.

Bob