Leach testing my cookware for heavy metals

Natural Baby Mama Cookware, Kitchen, Your Home

I decided to do a little test on my cookware to find out if heavy metals were leaching into my food.  I wanted to know specifically if my Le Creuset cookware or my stainless steel cookware was leaching toxic heavy metals into my food.

I moved away from using stainless steel when I started reading more about nickel and chromium leaching.  Trying to find truly non-toxic cookware has been hard.  After moving away from stainless I started using Le Creuset more.  I was specific about which Le Creuset I used.  Several years ago I tested my Le Creuset for heavy metals like lead and cadmium.  After that test, I no longer used any Le Crueset made in China (which are all the ceramic ones).  Mine tested poorly (lead and cadmium at high levels on the both the interior and exterior).   The cast iron from France tested bad for some colors on the exterior (like red) and good for other colors.  My blue Le Creuset tested pretty good – lead and cadmium free on the inside and lead free on the outside but low levels of cadmium on the outside of some but not all.  I was told by the company it was leach tested and there were no concerns.  Le Creuset has stated that Dune and Palm are the only colors that are lead and cadmium free.  I tested Dune and Palm myself and found trace levels of cadmium on the outside only.  After questioning the enamel on the inside, I had some concerns about aluminum being present, I decided to test it myself.  I couldn’t get a definitive answer from Le Creuset – they would not confirm on deny it.  So off I went to do a little experiment in my kitchen!

How did I test?

I did a pasta sauce test.  Why pasta sauce?  Because it’s acidic.  I wanted something that would be acidic so I could know if toxins were entering my food.

First, I bought some organic pasta sauce in a glass jar (Field Day Organics).  I bought a brand I don’t normally use because it was cheaper and I needed multiple jars.

Second, I mixed all the pasta sauce together in a bowl.  I did this to get a before sample.  I needed to know what the starting values were.


Before sample of all jars of pasta sauce mixed together








Third, I put pasta sauce into 4 pans:

  • 1 red Le Creuset skillet with a black interior.  The black interior has been scratched up, it’s a little hard to tell in the picture because it is black and cast iron is below it.  This pan tested for high cadmium on the exterior but lead and cadmium free on the interior.  I specifically used to this to see if cadmium from the exterior was entering our food.
  • 1 blue Le Creuset sauce pan with a cream interior with no scratches.  This tested clean for lead and some low cadmium on the exterior.  The interior is lead and cadmium free.   I specifically used this one because there were no scratches and Le Creuset claims they the leach testing shows they don’t leach.
  • 1 Dune Le Creuset sauce pan with a cream interior that was scratched up.  This color Le Creuset states is lead and cadmium free.  From my testing I showed very low levels of cadmium on the exterior which would be considered trace.
  • 1 Calphalon stainless steel pan.  This was bought in my pre non-toxic days so I did zero research on it.  Recently I looked it up and it has an aluminum core.  I’ve heard many people say aluminum will not leach through the stainless steel.

Red Le Creuset


Blue Le Creuset


Dune Le Creuset


Calphalon Stainless Steel







Fourth, I cooked each for 30 minutes.  I let cool for another 20 minutes.  I used separate spoons to stir each sauce as to not potentially cross contaminate.







Then, I put them in ziplock bags per the instruction of the lab.  They stated that the ziplock bags would not interfere with any of the testing since what I was testing for was not in the bags.


All done cooking (and cooling) and scooped out into ziplock bags


Samples ready for the lab to leach test for toxic heavy metals






Finally, I dropped them off at a lab to test for the heavy metals below.  I didn’t test all for each of the metals.  You will see below which metals I tested for in which pan.

  • lead
  • cadmium
  • nickel
  • chromium
  • aluminum

To re-cap:  I sent 5 samples of pasta sauce to a lab to be tested for heavy metals that could be leaching from my cookware.  I sent a non-cooked before sample, a sample from each of the cookware listed above (red Le Creuset, blue Le Creuset, Dune Le Creuset, and Calphalon stainless steel pan).  The lab tested for lead, cadmium, nickel, chromium and aluminum.

How did the lab test?

They weighed out each sample to approximately 5 grams.  The 5 gram sample was digested with hot mineral acids, brought to a final volume of 50 mls before the sample was injected into the instrument.

My results are as follows:

*** Please note, the less than values are just that.  Less than that number.  Which means it could be zero or it could be the number right below the less than value.***

***The numbers in bold are actual values, not less than values.***

 ug/g = ppm Before Sample Red LC % increase Blue LC % increase Dune LC % increase SS % increase







































What does this all mean?

First a few obvious results:

  1. Aluminum INCREASED in all my pots.
    1. Most significant was in my scratched Dune Le Creuset.  However, my red Le Creuset is also scratched and it didn’t increase to the same level.  My initial reaction is that there is aluminum in the enamel.
    2. My stainless steel has an aluminum core, like most stainless steel pots.
    3. The next question for me is if it is leaching or if aluminum is increasing because of the pasta sauce cooking down (or both).
    4. Yes, the before sample of pasta sauce has aluminum – ugh.
  2. Cadmium increased in the red Le Creuset which I know has high levels of cadmium on the outside.
  3. Cadmium increased in the Dune Le Creuset by the highest amount!  This is suppose to be lead and cadmium free.  The Dune pot I had tested with an XRF had low levels of cadmium on the exterior and nothing on the interior.  I did not test my specific pot.
  4. The rest of the values could all be zeros or could all be as high as the percentages I listed above.  So this information is not so informative.
  5. Separately I also tested a Le Creuset with an XRF to see if there was aluminum.  It tested positive but with the thin coating I was told I could be getting false positives.

What’s next:

I’m going to test a Le Creuset for aluminum at a certified lab and report back.  This is the only way to know for certain if there is aluminum in the enamel even though it is pointing to having aluminum.  I will not be doing a leach test but a destructive test where they break apart the pan to test for aluminum.

I’ll probably also have a lab do a leach test of nickel, chromium, and aluminum on the stainless steel pan.

What am I cooking in now!?

Good question.  You can read my cookware post to find out what I am currently using.


Stay tuned!


Interested in reading more:

Testing consumer goods for lead

Non-Toxic Toys

Non-Toxic Kitchen Items

Non-toxic Baby Registry





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