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Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

theguardian.com

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

#81

Post by verisimilitude »

cjlars wrote: post #62

I recently retrofit a new HVAC system and as a result have also gone on a bit of a deep dive on indoor air quality. The big thing I learned is that most homes -- even old "leaky" builds -- have rather poor ventilation, meaning all sorts of compounds build up in the air... CO2, formaldehyde, VOCs, PFAS, etc. Air purifiers work for particulate, but don't really make a dent for chemicals. IIRC, You would need like a 50…

Energy Recovery Ventilators or Heat Recovery Ventilators are absolutely essential (and, I think, part of code in many places!) in this era of tight and sometimes extraordinarily tight (e.g. Passivhaus) home building.

When we bought our home, the HRV wasn't working and once I replaced a bunch of parts in it, the difference in the quality of the air was noticeable just in the fact that it smelled fresh like the outdoors.

In your deep dive, you probably ran into the evergreen debate about running ERV/HRVs in the summer... I just gave up, turn it off when we run the A/C and open the windows occasionally... BUT I think you could probably run a humidistat/hygrostat hooked to the HRV (a common option in the new units, I believe).

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

#82

Post by meristohm »

slumdev wrote: post #7

My takeaways: 1. Open the windows as often as weather allows. 2. Don't use nonstick pans unless they're cast iron or some kind of fired enamel. 3. Use a water purifier.

Contrary responses aside, these three actions seem healthy. I’ll add that I’d like to see regulation towards cleaner air, water, and land, so that avoidance/mitigation is less necessary.

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

#83

Post by nate_meurer »

atom_arranger wrote: post #24
nate_meurer wrote: post #13

Earlier quoted context omitted.

There are no mobile PFAS chemicals in nonstick cookware. Nonstick coatings are made from PTFE, which is a completely inert polymer that cannot be broken down into mobile components unless it's overheated. The fluorinated chemicals used in the manufacture of the coatings (largely surfactants) are completely removed when the coating is baked on, and they have to be or else the coating would fail. PTFE is used in medica…

There aren't any long term studies comparing people who cook with non-stick vs stainless or cast iron, so we can only guess about long term and population level effects based on limited information. I personally would not take the risk given the benefit is just a pan that things stick to less. Medical uses are more justifiable.

No, we have lots of long term information about nonstick cookware. People forget we've been using teflon cookware since the 1950's. There have been billions of pieces of nonstick cookware in use every day around the world for decades.

The problem is that because there are so many free PFAS chemicals around us from other sources, studying the possible effects of cookware is a bit like studying whether it contains evil spirits. You won't be able to come up with a falsifiable hypothesis, because our PFC exposure via other routes is so high.

Another reason long term studies aren't viable is that there is no plausible mechanism of action of toxicity from nonstick cookware under the sort of use that it almost always gets. Unless it's badly overheated, PTFE is completely stable in inert.

Think about this logically: if you handle a water resistant jacket and then eat a sandwich, you'll ingest measureable quanities of PFAS. Every time kids or babies play on a stain-resistant carpetting and furniture, then ingest far greater quantities from their hands and toys.

In contrast, any PFAS that remains in nonstick cookware would be on the edge of detectability. PFAS surfactants are used in the manufacture of the coatings, but it boils off when the coating is baked on, and as far as I know, no detectable PFAS has ever been verified in finished cookware. Even when agressively overheated, nonstick cookware doesn't emit PFAS. It sublimates micro-size PTFA particles, which can lead to what we call "fume fever" but reports of this actually happening are rare, even in factory workers who are exposed at much higher levels than a home cook is.

So put these two things together: you are likely ingesting millions of times more PFAS from your clothes, carpets, and furniture than you ever could from nonstick cookware.

Worrying about nonstick cookware is sort of like a lifeguard who works in the sun all day, but obsessively blacks out the windows in his home because he's worried about UV radiation getting in his house. It makes no sense.

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

#84

Post by kongolongo »

doitLP wrote: post #40

The problem is not PFAS. It is extreme regulatory capture that got us to the this point. Even if we ban PFAS tomorrow, there are other alternatives that will be used and another 2 decades of lies and cover ups before we find out what harm those chemicals have. Example: look at what happened when BPAs harms became known. Manufacturers switched to using any of the other 40 chemicals in the same bisphenol family (BPS, e…

>We need to flip the approval process on its head -- from "safe until proven otherwise" to "unsafe until (independently) proven safe". The tally of harm to all life caused by these chemicals is on a massive scale that any mass murderer would be proud of.

That isn't always practically feasible and its a really tough problem to solve. Consider all the ways a compound released into the environment can break down and how long it might take for any exposure or even low levels of exposure might take to have any adverse health affects. The type of evidence you'd need to gather to demonstrate any compound is fully safe with that bar would make it nearly impossible to declare anything safe.

Microplastics, PFAS, and other compounds with potential long-acting health impacts are very hard to predict far in advance. Strong evidence against any adverse health effects would take considerable effort to gather while in the mean time they would offer massive clear benefits and solve so many problems. Plastics have massively reduced costs in almost every industry and have become almost irreplaceable in some applications such as medical equipment (think packaging for syringes, surgical tools, or anything that requires contamination control). Yet how they break down into microplastics in the environment and then eventually bioaccumulate in our tissues through the food chain is something that would've been extremely hard to predict at the onset of their creation. Even now we don't know if they're necessarily harmful.

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

#85

Post by BoxOfRain »

asdswe wrote: post #68
BoxOfRain wrote: post #58

Earlier quoted context omitted.

Which isn't without issues of its own of course, for example the EU is notoriously backwards on the issue of genetically modified crops which may turn out to be a vital lifeline if climate change causes agricultural collapse. Another example I can think of off the top of my head is the atrociously bad legislation to what was then the new technology of vaping, it came in pre-Brexit just when I was considering quitting…

We're still decades from a potential global agricultural collapse caused by climate change, there's plenty of time to study effects of GMO crops on environment and human health.

Decades is a short time on a planetary scale, at risk of sounding alarmist I really do believe we should be hoping for the best but preparing for the worst when it comes to climate change. If there was ever a time for action it was fifty years ago, but now is better than further delay.

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

#86

Post by danudey »

jszymborski wrote: post #63
BoxOfRain wrote: post #58

Earlier quoted context omitted.

Which isn't without issues of its own of course, for example the EU is notoriously backwards on the issue of genetically modified crops which may turn out to be a vital lifeline if climate change causes agricultural collapse. Another example I can think of off the top of my head is the atrociously bad legislation to what was then the new technology of vaping, it came in pre-Brexit just when I was considering quitting…

Sure, banning GMO's outright would be a huge problem, but is it so awful that they be tested first? I don't know if they test for this, but GMOs do run the risk of become invasive or destructive species which could potentially tilt things towards the "devastating famine" side of the equation. I don't think the ecological concern is what most people worry about when they think GMOs, and I'm not of the mind that GMOs =…

On one hand, the multiple levels of bureaucratic red tape and regulatory approval keeps a lot of technology from progressing onto the market and into people's lives at the rate it could otherwise.

On the other hand, the multiple levels of bureaucratic red tape and regulatory approval keeps a lot of technology from progressing onto the market and into people's lives at the rate it could otherwise.

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

#87

Post by fragmede »

BoxOfRain wrote: post #58
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.

Which isn't without issues of its own of course, for example the EU is notoriously backwards on the issue of genetically modified crops which may turn out to be a vital lifeline if climate change causes agricultural collapse. Another example I can think of off the top of my head is the atrociously bad legislation to what was then the new technology of vaping, it came in pre-Brexit just when I was considering quitting…

Part of the issue with GM crops is the corporations involved, and how to operate them ethically under capitalism. The EU has a much stronger stance against capitalism run amok, than the US' does, so even if you do trust the science, the science doesn't operate in a vacuum. The EU understands this.

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

#88

Post by meristohm »

verall wrote: post #79
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…

Because rice will still stick to the cast iron and enamel pans? People don't just choose PTFE because they are lazy. I tried a carbon steel, cast iron, and "oiled enamel" and rice stuck to all of them.

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 usually cook rice in inox/stainless saucepans or in ceramic in the pressure cooker. Eggs we cook in the seasoned iron pan. We can change our habits so that we don’t do so much harm to life on earth.

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

#89

Post by danudey »

chamsom wrote: post #16

California law TB117 required fire retardant foam until 2015 so a lot of couches have PFAS. This is an example of creating a problem by trying to avoiding another. Of course, this is not to single out CA as this is a global problem. Could be wrong but it seems like the general rule is that manufacturers are allowed to "experiment in public" when it comes to chemical science. PFAS alternatives are already in the wild…

Also, California's law that makes everyone label everything with "this product contains some measurable level of an identified carcinogen" means that no one pays attention to those labels when it's plastered on something like an asbestos breathing mask or lick-and-paint radon clocks, making them even worse than useless.

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

#90

Post by cjlars »

bumby wrote: post #75
cjlars wrote: post #62

I recently retrofit a new HVAC system and as a result have also gone on a bit of a deep dive on indoor air quality. The big thing I learned is that most homes -- even old "leaky" builds -- have rather poor ventilation, meaning all sorts of compounds build up in the air... CO2, formaldehyde, VOCs, PFAS, etc. Air purifiers work for particulate, but don't really make a dent for chemicals. IIRC, You would need like a 50…

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 humidity sensors. I think CO2 sensors are on the horizon though, here's a study featuring such a system: https://core.ac.uk/download/pdf/43245317.pdf

My current system is actually ductless however, so I will probably have to rely on natural diffusion... I do have an air quality monitor which indicates that diffusion is likely sufficient (for a one floor open plan condo), but you'll optimally need to sleep with the bedroom doors open.

Edit: I haven't looked too deeply at the standards. My little sensor indicates that if you keep CO2 in range, VOCs will also also be in range, which conforms with my intuition.

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