Toxic ‘forever chemicals’ contaminate indoor air at worrying levels • Hacker News Board

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#101

Post by nate_meurer » Tue, Aug 31, 2021, 6:08 PM UTC

yabones wrote: post #44

kaitai wrote: post #38

Earlier quoted context omitted.

People "overheat" their cookware all the time. Do you know anyone who measures the temp of the surface of their cookware? Teflon and nonstick coatings kill birds (house pets) when overheated. A nonstick pan in the oven to catch the drippings from your chicken baking at 400 or 425 can kill your parrot quickly. A nonstick wok left unattended for a few minutes during a high-heat stir fry easily reaches 400, enough to ki…

Cast iron pans are wonderful. I inherited one that was purchased originally in 1929. It's used every day or two to cook eggs for breakfast, and as I've found over the years butter is fantastic for keeping the seasoning in great shape. It's more non-stick than teflon, just a little shake is enough to send my eggs sliding to the other side of the pan. All it takes is discipline. Best part is, this same pan will probabl…

I agree, I love vintage cookware. My favorite pans are a bunch of All-Clad LTD's I assembled from Ebay over the years. I use them for omelettes and french toast. Super thick aluminum clad with a stainless cooking surface, made sometime in the 1980s. They're as tough as cast iron, but they heat way more evenly, they're much lighter, and you don't have to worry about hurting the seasoning.

With cast iron, you can easily destroy the seasoning by overheating the pan, or if your mother who doesn't know how to care for cast iron puts it in the dishwasher. I put my All-Clads in the sink and scrub them with a steel tuffy. They're probably the most indestructable tools I own.

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#102

Post by nate_meurer » Tue, Aug 31, 2021, 6:13 PM UTC

verall wrote: post #98

meristohm wrote: post #88

Earlier quoted context omitted.

I might go with “because they are lazy” for many of the shortcuts we take. We have one well-seasoned cast-iron pan and several not-so-well-seasoned which I’ve been too lazy to properly treat, so for now I spend the extra time scrubbing. I even use soap (!), though only after the dog gets the big stuff off. Teflon pans required too much care, so we never repaced them. I agree that rice sticks easily to iron pans, so I…

I think that you are correct in most cases, people choose nonstick for the easy cleanup afterwards. But that's not what I'm referring to. I have not found a pan, other than PTFE coated, which can fry rice to crispy without using excessive tons of oil. All of the best crispy rice will get stuck to the pan and become inedible.

This is my experience as well. I also use a lot of slowly sauteed garlic, like pretty much every day, and I'm completely reliant on a small nonstick pot to do it without sticking and burning.

Scrambled eggs too, especially the soft-scrambled kind ala Gordon Ramsay's famous short video. They simply wipe out of nonstick pan, and I've never seen this work with any other kind of cookware.

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#103

Post by bumby » Tue, Aug 31, 2021, 6:15 PM UTC

cjlars wrote: post #90

bumby wrote: post #75

Earlier quoted context omitted.

Did you find any industry ventilation standards related to all the compounds you listed? IIRC, ASHRAE 60.1 is the industry standard but years ago at least, it was based mainly on using "bio-effluence" as a proxy for air quality. I.e., reducing stink. > install an energy recovery ventilating system. These are a good idea, but the exact type is important or else you risk cross-contamination between the exhaust and inta…

I think an ideal heat recovery system would probably sit mid-stream in a central air system with a built in CO2 trigger. Basically, the return air gets exhausted while heating the incoming/supply air when CO2 concentration > X. Obviously you run into the capex vs ongoing energy cost tradeoff in designing the system. Strangely, I couldn't find a ventilator on market with a CO2 sensor, but there are plenty with humidit…

>Basically, the return air gets exhausted while heating the incoming/supply air when CO2 concentration > X.

That’s the basic idea of demand control ventilation but how are the two air streams interfacing? If our concern is air quality, how is cross contamination between the two mitigated?

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#104

Post by Lutzb » Tue, Aug 31, 2021, 6:24 PM UTC

refurb wrote: post #64

ashildr wrote: post #42

Earlier quoted context omitted.

> from "safe until proven otherwise" to "unsafe until (independently) proven safe" That’s about how the EU does it.

No, that’s not how the EU does it. https://en.m.wikipedia.org/wiki/Benfluorex A drug that was highly suspected of killing several hundred to several thousand people stayed on the market for decades. A similar drug with similar risks was pulled from the US market 24 years earlier .

Would you say Benflourex is an outlier or the norm regarding the EUs stance?

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#105

Post by cjlars » Tue, Aug 31, 2021, 6:29 PM UTC

bumby wrote: post #103

cjlars wrote: post #90

Earlier quoted context omitted.

I think an ideal heat recovery system would probably sit mid-stream in a central air system with a built in CO2 trigger. Basically, the return air gets exhausted while heating the incoming/supply air when CO2 concentration > X. Obviously you run into the capex vs ongoing energy cost tradeoff in designing the system. Strangely, I couldn't find a ventilator on market with a CO2 sensor, but there are plenty with humidit…

> Basically, the return air gets exhausted while heating the incoming/supply air when CO2 concentration > X. That’s the basic idea of demand control ventilation but how are the two air streams interfacing? If our concern is air quality, how is cross contamination between the two mitigated?

I was confused at first by a lot of diagrams I found online, but the wiki is pretty good. Basically think of a two way radiator. Hot air flows through air channel blades on the way out, cold air flows around the blades on the way in, with filtering optional at this point. Some systems indicate that they literally mix the air, which is obviously not going to be optimal, the air needs to be fully separated with the energy exchanging through a metal layer.

https://en.wikipedia.org/wiki/Energy_recovery_ventilation

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#106

Post by nate_meurer » Tue, Aug 31, 2021, 6:32 PM UTC

slumdev wrote: post #96

nate_meurer wrote: post #94

Earlier quoted context omitted.

> "Did any birds die?" is an approach to this problem that I would expect from an undeveloped nation a hundred years ago. It is both excruciatingly short-term in focus and so imprecise that the results are useless for anyone who is not himself a rat or a canary. I sort of agree, but birds do make a convenient study subject because they are exquisitely sensitive, much more so than humans. The lowest temperature at whi…

The last time I needed an x-ray for a broken bone, I asked the x-ray tech for a lead vest to protect my torso and groin area. He told me that it was pointless because I would be exposed to more background radiation throughout the course of my normal life. He did not understand that ionizing radiation damage is cumulative and that there is no safe limit for exposure. Annoyed with my request, he gave me the vest anyway…

You were right to ask for a shield. I would do the same thing, and I'd be a little pissed that I had to ask.

However there's a big difference, in that the x-ray you got actually delivers a substantial amount of ionizing radiation-- up to one full percent of the average annual background dose. There is no evidence that even a lot of normal x-ray scans have any effect on health, but at least it's a physical possibility.

In contrast, the level of chemical hazard from nonstick cookware is a billionth or trillionth (or even smaller) than what's in the carpets we all grew up playing on, or the clothes we wear and furniture we sit on every day.

To use another analogy, worrying about nonstick cookware is like worrying about the ionizing radiation coming from a banana that's sitting uneaten across the room from you.

I agree about absestos, and I fee the same about lead as well. Those are nasty poisons that, contrary to popular lore, cannot be used and applied safely such that they won't eventually get loose and become a health hazard. I've been thinking about asbestos this week because I've been replacing ceiling light fixtures in my house, and it's impossible to do without causing the asbstos-filled popcorn texture to rain down like snow. It's fucking unbelievable what previous generations afflicted us with.

EDIT:

I feel compelled to repeat that common cooking fumes and smoke are known toxins and carcinogens. It makes no sense to be more concerned about tiny amounts of aerosolized PTFE than the far greater amounts of cooking smoke and fumes that will inevitably be emitted by your food at the same temperatures.

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#107

Post by [deleted] » Tue, Aug 31, 2021, 6:33 PM UTC

camgunz wrote: post #97

ffhhj wrote: post #45

I'm designing a wearable device, and I'm looking for resistant materials, different from metals, that are safe to use on the skin. According to Wikipedia PTFE (teflon) is not harmful. Could someone recommend materials to protect the electronics from sweat/dirt and the skin from the device silicone?

Well, teflon is a "forever chemical" (PFAS) and the consensus seems to be it's not wonderful if it gets inside of you [1]. Silicone is a PFAS alternative and a little safer, but also not wonderful if it gets inside of you [2]. All of which is to say that your device should be OK as long as no one puts it inside them. AFAIK anyway. [1]: https://www.cancer.org/cancer/cancer-causes/teflon-and-perfl... [2]: https://www.h…

[deleted]

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#108

Post by ectopod » Tue, Aug 31, 2021, 6:36 PM UTC

strict9 wrote: post #39

ashildr wrote: post #33

Earlier quoted context omitted.

This is really strange - I’m in Germany and I hear for the first time that underwear is treated like this. None of the brand I wear (HOM) seem to be and I don’t remember that being mentioned on any pack of underwear I purchased the last 40 years. Is it an US thing? (and yes, I’m posting about my underwear on hacker news. weird.)

It is strange! It's a recent thing in the US, yes. Probably in the past 4-5 years nearly all major brands put some sort of special chemical that gives it 'moisture wicking' (usually in partnership with Dow or 3M).

I just bought some new underwear from Marks & Spencer in the UK which has their "Cool & Fresh" treatment. I haven't worn it yet but this thread is putting me off.

M&S publish a Manufacturing Restricted Substances List [1] for their suppliers, which seems to ban the use of all per- and poly-fluorinated chemicals in the manufacture of textiles for them.

Either I'm misunderstanding, or some of these underwear treatments don't involve PFAs. Who knows what they use instead?

[1]: https://corporate.marksandspencer.com/documents/plan-a-our-a...

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#109

Post by nate_meurer » Tue, Aug 31, 2021, 6:37 PM UTC

colechristensen wrote: post #29

nate_meurer wrote: post #19

Earlier quoted context omitted.

Wicking materials don't use PFAS (although see edit below). The properties that PFAS endows a fabric are pretty much of the opposite of what you need for wicking. Wicking fabrics such as Capilene and polypropylene must be wettable in order to work. PFAS reduces the wettability of fibers. That's its whole point. PFAS is used in nearly all current water resistant fabrics, including clothing, upholstery, and carpet. The…

Waxed canvas is also waterproof and free of questionable chemistry and is delightful.

I agree. My favorite hat is oilcloth, and it's as waterproof as any fancy modern gear.

Re: Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

#110

Post by EricE » Tue, Aug 31, 2021, 6:38 PM UTC

cjlars wrote: post #90

bumby wrote: post #75

Earlier quoted context omitted.

Did you find any industry ventilation standards related to all the compounds you listed? IIRC, ASHRAE 60.1 is the industry standard but years ago at least, it was based mainly on using "bio-effluence" as a proxy for air quality. I.e., reducing stink. > install an energy recovery ventilating system. These are a good idea, but the exact type is important or else you risk cross-contamination between the exhaust and inta…

I think an ideal heat recovery system would probably sit mid-stream in a central air system with a built in CO2 trigger. Basically, the return air gets exhausted while heating the incoming/supply air when CO2 concentration > X. Obviously you run into the capex vs ongoing energy cost tradeoff in designing the system. Strangely, I couldn't find a ventilator on market with a CO2 sensor, but there are plenty with humidit…

CO2 sensors are common in commercial HVAC systems - especially for large auditoriums or rooms where you expect high occupancy. Economizers will automatically open to increase the exchange of outside air. My church has an auditorium that can seat up to 1500 - all four AC units have CO2 detection built into them and the concentration is displayed on the controls too.