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Comment by forgotmypw17 | Hacker News Reader

If you want to gamble with your health while the jury is still, technically, out, I can't stop you...

> At normal cooking temperatures, PTFE-coated cookware releases various gases and chemicals that present mild to severe toxicity.

> Only few studies describe the toxicity of PTFE but without solid conclusions.

> There are some reports where PFOA was detected in the gas phase released from the cooking utensils under normal cooking temperatures.

> Due to toxicity concerns, PFOA has been replaced with other chemicals such as GenX, but these new alternatives are also suspected to have similar toxicity.

> The toxicity and fate of ingested PTFE coatings are also not understood.

Source:

PTFE-coated non-stick cookware and toxicity concerns: a perspective

Muhammad Sajid 1, Muhammad Ilyas 2

PMID: 28913736

DOI: 10.1007/s11356-017-0095-y

https://pubmed.ncbi.nlm.nih.gov/28913736/

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> At normal cooking temperatures, PTFE-coated cookware releases various gases and chemicals that present mild to severe toxicity.

I don't think it means what you think it means. Reading further into the paper, it says

>At normal use conditions [< 230 °C], total emissions of PFCAs were 4.75 ng per hour

Which seems absolutely tiny. If spread out the emissions across the hour (because the 4.75 ng figure was cumulative emissions), the exposure to the cook would be in the parts per trillion range.

I guess it's all relative and a matter of opinion...

4.75 nanograms may not seem like a lot, but when you consider that, at 414.07g/mol it is 6,908,293,060,000 parts of the stuff, it seems like quite a bit to me. And that's in just one cooking session.

Please correct me if I'm wrong, it's been a while since my chemistry class.

The EPA drinking water standards, the ones watered down by industry influence, are measured in parts per trillion.

Here is a science question for you: If the EPA limit for PFOA in drinking water is 70 parts per trillion, what volume of water would need to be mixed with 4.75 nanograms of PFOA in order to bring that water to within the allowable limit for drinking water?

Now, here is a quote from the EPA:

> These studies indicate that exposure to PFOA and PFOS over certain levels may result in adverse health effects, including developmental effects to fetuses during pregnancy or to breastfed infants (e.g., low birth weight, accelerated puberty, skeletal variations), cancer (e.g., testicular, kidney), liver effects (e.g., tissue damage), immune effects (e.g., antibody production and immunity), thyroid effects and other effects (e.g., cholesterol changes). There is limited information identifying health effects from inhalation or dermal exposures to PFOA or PFOS in humans and animals.

Based on this question, do you think there are any "health effects" if exposed to PFOA and PFOS below these "certain levels".

>4.75 nanograms may not seem like a lot, but when you consider that, at 414.07g/mol it is 6,908,293,060,000 parts of the stuff, it seems like quite a bit to me.

This doesn't prove anything part from molecules being really small. What's more important at what doses do negative health effects materialize.

>And that's in just one cooking session.

I'm not sure about you but 1 hour is an usually long time to be using a frying pan. Unless you're cooking a huge slab of meat, letting anything sit in a 230C degree pan for an hour would result it being burnt/overcooked.

>The EPA drinking water standards, the ones watered down by industry influence, are measured in parts per trillion.

Looking through https://www.epa.gov/ground-water-and-drinking-water/national..., the only one that I can find that's near 1 part per trillion is dioxin, at 0.03 PPT. The rest are well above that. Furthermore, even 1 part per trillion is a high estimate for actual exposure. In addition to being spread out across an hour (3600 seconds), the emissions are also dispersed across the room and vented out. Finally, like I pointed out earlier, what maters more is the toxicity of the compound. Dioxins and PFCAs are both "bad", but it doesn't mean they're equally as toxic. The limit for mercury is orders of magnitude higher at 2 parts per billion.

Googling for "epa pfoa", I found this page, where the limit is listed as 70 parts per trillion:

https://www.epa.gov/ground-water-and-drinking-water/drinking...

Did you get a chance to take a crack at the chemistry math problem I posed?

Once you've solved that one, here is another one for you:

If 4.75 nanograms of the material is aerosoled out into the air, what amount is absorbed directly into the food which is cooking on the pan?

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