13 ms·

Toxic ‘forever chemicals’ contaminate indoor air at worrying levels

200 points by hiddencache 5y ago

defaulty 5y ago
Are there air purifiers that filter these? I have not seen them on list of what air purifiers can filter
- Cthulhu_ 5y ago
  Regular HEPA filters should be able to filter these, but I'll admit I don't know what size these particles are. If they're single molecules it may be a problem.
- neom 5y ago
  "HEPA filters capture pollen, dirt, dust, moisture, bacteria (0.2-2.0 μm), virus (0.02-0.3 μm), and submicron liquid aerosol (0.02-0.5 μm).[8][9][10] Some microorganisms, for example, Aspergillus niger, Penicillium citrinum, Staphylococcus epidermidis, and Bacillus subtilis are captured by HEPA filters with photocatalytic oxidation (PCO). HEPA is also able to capture some viruses and bacteria which are ≤0.3 μm." "Eleven particle-size-segregated samples were taken to investigate the particle-size distribution of perfluoroalkyl substances (PFASs) using two five stage impactors in parallel. ... Particle-size distribution varied between perfluorooctane sulfonate (PFOS) and other perfluoroalkyl sulfonates (PFSAs), perfluorooctane carboxylate (PFOA) and other perfluoroalkyl carboxylates (PFCAs) and n-methyl-perfluorooctanesulfonamido ethanol (MeFOSE). Whereas PFOA and MeFOSE were predominantly observed in smallest size fraction (<0.14 μm), maximum PFOS mass fractions were observed in the coarser size fractions between 1.38 and 3.81 μm." https://en.wikipedia.org/wiki/HEPA https://en.wikipedia.org/wiki/HEPA https://www.sciencedirect.com/science/article/abs/pii/S0045653514008169 https://www.sciencedirect.com/science/article/abs/pii/S00456...
  - pdabbadabba 5y ago
    For those uninterested in digesting these details, the upshot of this seems to be: Yes. HEPA filters should capture these. Edit: Though perhaps inefficiently. See the replies below.
    - DoingIsLearning 5y ago
      Hold on, that is very much the opposite of my interpretation. HEPA filters are typically designed with 0.3μm pores this is mostly a legacy of medical applications (i.e. to guarantee they catch bacteria). Submicron performance (< 0.3μm) is kind of down to luck. You need the submicron particle to travel on a larger liquid particule for it to adhere to the filter lattice. The PFAS is a group of substances, the article is specifically talking about 6:2 FTOH (one of many PFAS substances) that is found in carpets etc. 6:2 FTOH specifically is a sub-micron compound, from the GP article the closest particle to it is PFOA which is <0.14 μm. So unless your 6:2 FTOH compound is travelling on a moisture particle it is unlikely it would be filtered. To answer GGP question, a high MERV rating filter will probably catch some of these compounds but not the totality. Open your windows frequently (if outside air pollution allows wherever you live) and make sure you understand what products you have in your house.
      - tzs 5y ago
        > You need the submicron particle to travel on a larger liquid particule for it to adhere to the filter lattice That's what intuition would suggest, but intuition turns out to be wrong when dealing with filters for microscopic things. There are at least four mechanisms by which a filter can trap particles, three of which work on particles smaller than the pores [1]. Briefly: 1. Big particles don't fit between the fibers of the filter. Think fish in a fish net. This is called sieving. 2. Particles too small for sieving but heavier than the surrounding flow don't make the turns as well as the surrounding flow when the flow goes around the fibers. The particles can get embedded in the fibers. This mechanism is called inertial impaction. 3. The smallest might be too small to actually be affected much by the flow of the surrounding fluid through the filter. The move by diffusion, and many will randomly hit the fibers and get stuck. 4. Particles too big for diffusion but too light for inertial impaction still can run into fibers and get stuck. This is called interception. The effectiveness of sieving, inertial impaction, and interception all follow S shaped curves that start out low for small particles, then at some point start rising, and then level out. The sieving curve's rise is almost vertical. The rise for inertial impaction is steep but not nearly as steep as it is for sieving. The curve for interception's rise is much more relaxed. The effectiveness for diffusion goes the other way. Much more effective for very small particles, then above some size drops down and is low from then on. When you put all these together, you get a curve that is effective at the small end, and at some point as size goes up effectiveness drops, reaching a minimum, and then rises again to reach high effectiveness for particles above some certain size. There is also a fifth mechanism in some filters where electrostatic attraction between the fibers and the particles catches some particles. [1] https://donaldsonaerospace-defense.com/library/files/documents/pdfs/042665.pdf https://donaldsonaerospace-defense.com/library/files/documen...
q_andrew 5y ago
This contributes to the theory that PFAS is affecting ambient obesity rates in the modern world: https://slimemoldtimemold.com/2021/07/26/a-chemical-hunger-part-vi-pfas/ https://slimemoldtimemold.com/2021/07/26/a-chemical-hunger-p...
- nradov 5y ago
  There appears to be a similar issue with other endocrine disruptor chemicals like phthalates (plastic softeners) possibly increasing the risk of obesity. But those are typically polluting food rather than air. https://www.endocrine.org/topics/edc/what-edcs-are/common-edcs https://www.endocrine.org/topics/edc/what-edcs-are/common-ed...
  - deleted 5y ago
    [deleted]
- GuB-42 5y ago
  It may be a contributor but there are so many "obvious" things that cause obesity in the modern world that a paper needs really strong arguments with a rigorous statistical analysis with confounding factors in order to draw conclusions. The obvious include: high availability of energy-rich, cheap food, lower amount of physical activity, food designed to be addictive (usually with lots of sugar),... There is also a strong correlation between obesity and low socioeconomic status, that can be also explained by "obvious" factors, like irregular meals, less physical activity, cheap, energy-rich, nutrient-poor food and poor education regarding healthy habits.
  - smallerfish 5y ago
    The slimemold series addresses those. It's worth a read.
- thatfrenchguy 5y ago
  As someone who immigrated from France to the US, it’s pretty obvious why people in the US are obese: people don’t know / don’t have the time to know how to eat properly and eat junk food, all the time, at any hour, and don’t move around. It’s pretty obvious when you realize that there is a lot less overweight people in upper middle class areas.
detcader 5y ago
I can't stomach the science "journalism" here. Most of the statements about the research is that studies "found" the chemicals here or there. Ok, I can "find" various sources of cancer-related radiation in my sock drawer. Particularly annoying: "It found particularly high levels in several kindergarten classrooms and also checked the supply room of an outdoor clothing store, offices, several university classrooms, university labs and an elevator." Thank goodness we the public have the crucial information that the study checked these places.
- ashildr 5y ago
  Yes, this is disappointing.
slumdev 5y ago
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.
- nradov 5y ago
  In California now it seems like we have an extended wildfire season every summer where no one wants to open the windows due to bad air quality.
  - sgc 5y ago
    But we are also running hepa filters inside for the same reason.
- nate_meurer 5y ago
  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 medical implants. You can eat it. In no case that I'm aware of have these things resulted in detectable fluorinated compounds in someone's blood stream.
  - atom_arranger 5y ago
    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.
    - gruez 5y ago
      >I personally would not take the risk given the benefit is just a pan that things stick to less. Being able to use less cooking oils is a material benefit, especially considering the obesity rates we see in the developed world.
hmm320 5y ago
How does one know if their clothing is PFAS-free if it doesn't specifically say?
- chamsom 5y ago
  If your clothing is waterproof or has some kind of exercise "moisture wicking" material, it is common to have PFAS.
  - strict9 5y ago
    An absurd challenge: walk to into a target or some other large retail store and try to find mens briefs that do not have moisture wicking treatment. It feels like I'm in a strange dystopia trying to find undergarments not treated with some sort of PFAS additives.
    - AlgorithmicTime 5y ago
      I don't think PFAS are for moisture wicking. More water/moisture repelling. Also, go to Costco and there's a 3 or 4 pack of 100% cotton boxer-briefs on sale.
    - dd36 5y ago
      Me too but for undershirts! I didn’t see your comment before making mine.
    - ashildr 5y ago
      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.)
      - strict9 5y ago
        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).
chamsom 5y ago
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 and we don't know what those do either. Here's what you can do: 1. Open windows to your house, but also your car which contains PFAS in the upholstery 2. Minimize dust w/ vacuum, HEPA filters 3. Reduce use of old couches which stirs up dust until you replace it 4. Minimize polyurethane foam products - polyster foam is better 5. Paper/biodegradable takeout containers and fast food packaging have PFAS lined so the paper doesn't absorb oil etc.
- l30n4da5 5y ago
  > HEPA filters This is probably the most important. If you work from home, it might be prudent to at least have a one-room HEPA filter in your home office.
  - intrasight 5y ago
    I have in furnance airflow and also one in bedroom.
    - barbazoo 5y ago
      I'm having trouble figuring out what kind of filter I can use for my furnace. I've read a little bit about it and it seems that a residential furnace might not be able to handle the HEPA filter due to the higher airflow resistance. Even MERV 13 might already be too high.
      - bradfa 5y ago
        The MERV or other rating of a filter is not what's important to your furnace (it's what's important to the humans) but what matters is how much airflow through the filter can be achieved by the furnace fan and how much pressure drop the filter induces. If you get a MERV 12 filter with LOTS of filter material, it may flow more air at a lower pressure drop than a MERV 6 filter with minimal filter material. Look for more pleats in the filter or modify (or hire an HVAC contractor to modify) your furnace filter cabinet to accept a thicker filter cartridge. For reference, in my furnace during an HVAC consultation, we saw the same 0.5 inches of water pressure drop from a cheap 3M Filtrete MERV 7 filter as with a K&N reusable MERV 12 filter. The K&N has MUCH more filter material. You don't want to restrict the airflow to your furnace any more than is necessary. Most furnaces will have their required maximum pressure drop from the duct work and filter printed on a label inside. You can get a differential pressure meter to measure the actual pressure drops yourself, or hire an HVAC technician to do an audit of your furnace (often they'll do lots of other neat tests and give you lots of data and reports and info, too).
doitLP 5y ago
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, etc) many of which had even worse safety profiles, while proudly proclaiming their products were "BPA free". 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.
- ashildr 5y ago
  > from "safe until proven otherwise" to "unsafe until (independently) proven safe" That’s about how the EU does it.
  - ironmagma 5y ago
    How can you prove anything safe without data on its use? Isn't that sort of a chicken and egg problem?
    - sooheon 5y ago
      Should the data be collected without consent by exposing the public to it for decades or provided by clinical trials funded by the company that wants to bring it to market?
      - qweqwweqwe-90i 5y ago
        You are asking for the impossible. It can be impossible to tell with things that only have no - to mild effects. Proving a negative ("this is not dangerous") is hard :)
        sooheon 5y ago
forgotmypw17 5y ago
,,cleaning,, products, even dish and hand soap new furniture and clothes any sort of spray or solvent ... read the ingredients if available avoid if it smells synthetic avoid places where you encounter them ... edit: for the downvoters, try googling "indoor air pollution voc" example: https://www.bbc.com/future/article/20200909-why-indoor-air-pollution-is-an-overlooked-problem https://www.bbc.com/future/article/20200909-why-indoor-air-p...
ffhhj 5y ago
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?
- camgunz 5y ago
  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-perfluorooctanoic-acid-pfoa.html https://www.cancer.org/cancer/cancer-causes/teflon-and-perfl... [2]: https://www.healthline.com/health/body-modification/is-silicone-toxic#symptoms https://www.healthline.com/health/body-modification/is-silic...
  - deleted 5y ago
    [deleted]
- calvinmorrison 5y ago
  Rubber?
magwa101 5y ago
Do HEPA filters capture PFAS particles?
cjlars 5y ago
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 gallon drum of activated carbon to do anything on the chemical front. A quick solution is to crack the windows, or if you live in a non-temperate climate, install an energy recovery ventilating system.
- bumby 5y ago
  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 intake. That's why many designs (e.g., heat recovery wheels) are generally banned in some applications like healthcare. With the crowd that HN attracts, I'd be interested if anybody has implemented some sort of demand-control ventilation in their home.
  - cjlars 5y ago
    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 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.

200 points by hiddencache 5y ago

defaulty 5y ago

Are there air purifiers that filter these? I have not seen them on list of what air purifiers can filter

Cthulhu_ 5y ago
Regular HEPA filters should be able to filter these, but I'll admit I don't know what size these particles are. If they're single molecules it may be a problem.
neom 5y ago
"HEPA filters capture pollen, dirt, dust, moisture, bacteria (0.2-2.0 μm), virus (0.02-0.3 μm), and submicron liquid aerosol (0.02-0.5 μm).[8][9][10] Some microorganisms, for example, Aspergillus niger, Penicillium citrinum, Staphylococcus epidermidis, and Bacillus subtilis are captured by HEPA filters with photocatalytic oxidation (PCO). HEPA is also able to capture some viruses and bacteria which are ≤0.3 μm." "Eleven particle-size-segregated samples were taken to investigate the particle-size distribution of perfluoroalkyl substances (PFASs) using two five stage impactors in parallel. ... Particle-size distribution varied between perfluorooctane sulfonate (PFOS) and other perfluoroalkyl sulfonates (PFSAs), perfluorooctane carboxylate (PFOA) and other perfluoroalkyl carboxylates (PFCAs) and n-methyl-perfluorooctanesulfonamido ethanol (MeFOSE). Whereas PFOA and MeFOSE were predominantly observed in smallest size fraction (<0.14 μm), maximum PFOS mass fractions were observed in the coarser size fractions between 1.38 and 3.81 μm." https://en.wikipedia.org/wiki/HEPA https://en.wikipedia.org/wiki/HEPA https://www.sciencedirect.com/science/article/abs/pii/S0045653514008169 https://www.sciencedirect.com/science/article/abs/pii/S00456...
- pdabbadabba 5y ago
  For those uninterested in digesting these details, the upshot of this seems to be: Yes. HEPA filters should capture these. Edit: Though perhaps inefficiently. See the replies below.
  - DoingIsLearning 5y ago
    Hold on, that is very much the opposite of my interpretation. HEPA filters are typically designed with 0.3μm pores this is mostly a legacy of medical applications (i.e. to guarantee they catch bacteria). Submicron performance (< 0.3μm) is kind of down to luck. You need the submicron particle to travel on a larger liquid particule for it to adhere to the filter lattice. The PFAS is a group of substances, the article is specifically talking about 6:2 FTOH (one of many PFAS substances) that is found in carpets etc. 6:2 FTOH specifically is a sub-micron compound, from the GP article the closest particle to it is PFOA which is <0.14 μm. So unless your 6:2 FTOH compound is travelling on a moisture particle it is unlikely it would be filtered. To answer GGP question, a high MERV rating filter will probably catch some of these compounds but not the totality. Open your windows frequently (if outside air pollution allows wherever you live) and make sure you understand what products you have in your house.
    - tzs 5y ago
      > You need the submicron particle to travel on a larger liquid particule for it to adhere to the filter lattice That's what intuition would suggest, but intuition turns out to be wrong when dealing with filters for microscopic things. There are at least four mechanisms by which a filter can trap particles, three of which work on particles smaller than the pores [1]. Briefly: 1. Big particles don't fit between the fibers of the filter. Think fish in a fish net. This is called sieving. 2. Particles too small for sieving but heavier than the surrounding flow don't make the turns as well as the surrounding flow when the flow goes around the fibers. The particles can get embedded in the fibers. This mechanism is called inertial impaction. 3. The smallest might be too small to actually be affected much by the flow of the surrounding fluid through the filter. The move by diffusion, and many will randomly hit the fibers and get stuck. 4. Particles too big for diffusion but too light for inertial impaction still can run into fibers and get stuck. This is called interception. The effectiveness of sieving, inertial impaction, and interception all follow S shaped curves that start out low for small particles, then at some point start rising, and then level out. The sieving curve's rise is almost vertical. The rise for inertial impaction is steep but not nearly as steep as it is for sieving. The curve for interception's rise is much more relaxed. The effectiveness for diffusion goes the other way. Much more effective for very small particles, then above some size drops down and is low from then on. When you put all these together, you get a curve that is effective at the small end, and at some point as size goes up effectiveness drops, reaching a minimum, and then rises again to reach high effectiveness for particles above some certain size. There is also a fifth mechanism in some filters where electrostatic attraction between the fibers and the particles catches some particles. [1] https://donaldsonaerospace-defense.com/library/files/documents/pdfs/042665.pdf https://donaldsonaerospace-defense.com/library/files/documen...

q_andrew 5y ago

This contributes to the theory that PFAS is affecting ambient obesity rates in the modern world: https://slimemoldtimemold.com/2021/07/26/a-chemical-hunger-part-vi-pfas/ https://slimemoldtimemold.com/2021/07/26/a-chemical-hunger-p...

nradov 5y ago
There appears to be a similar issue with other endocrine disruptor chemicals like phthalates (plastic softeners) possibly increasing the risk of obesity. But those are typically polluting food rather than air. https://www.endocrine.org/topics/edc/what-edcs-are/common-edcs https://www.endocrine.org/topics/edc/what-edcs-are/common-ed...
- deleted 5y ago
  [deleted]
GuB-42 5y ago
It may be a contributor but there are so many "obvious" things that cause obesity in the modern world that a paper needs really strong arguments with a rigorous statistical analysis with confounding factors in order to draw conclusions. The obvious include: high availability of energy-rich, cheap food, lower amount of physical activity, food designed to be addictive (usually with lots of sugar),... There is also a strong correlation between obesity and low socioeconomic status, that can be also explained by "obvious" factors, like irregular meals, less physical activity, cheap, energy-rich, nutrient-poor food and poor education regarding healthy habits.
- smallerfish 5y ago
  The slimemold series addresses those. It's worth a read.
thatfrenchguy 5y ago
As someone who immigrated from France to the US, it’s pretty obvious why people in the US are obese: people don’t know / don’t have the time to know how to eat properly and eat junk food, all the time, at any hour, and don’t move around. It’s pretty obvious when you realize that there is a lot less overweight people in upper middle class areas.

detcader 5y ago

I can't stomach the science "journalism" here. Most of the statements about the research is that studies "found" the chemicals here or there. Ok, I can "find" various sources of cancer-related radiation in my sock drawer. Particularly annoying: "It found particularly high levels in several kindergarten classrooms and also checked the supply room of an outdoor clothing store, offices, several university classrooms, university labs and an elevator." Thank goodness we the public have the crucial information that the study checked these places.

ashildr 5y ago
Yes, this is disappointing.

slumdev 5y ago

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.

nradov 5y ago
In California now it seems like we have an extended wildfire season every summer where no one wants to open the windows due to bad air quality.
- sgc 5y ago
  But we are also running hepa filters inside for the same reason.
nate_meurer 5y ago
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 medical implants. You can eat it. In no case that I'm aware of have these things resulted in detectable fluorinated compounds in someone's blood stream.
- atom_arranger 5y ago
  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.
  - gruez 5y ago
    >I personally would not take the risk given the benefit is just a pan that things stick to less. Being able to use less cooking oils is a material benefit, especially considering the obesity rates we see in the developed world.

hmm320 5y ago

How does one know if their clothing is PFAS-free if it doesn't specifically say?

chamsom 5y ago
If your clothing is waterproof or has some kind of exercise "moisture wicking" material, it is common to have PFAS.
- strict9 5y ago
  An absurd challenge: walk to into a target or some other large retail store and try to find mens briefs that do not have moisture wicking treatment. It feels like I'm in a strange dystopia trying to find undergarments not treated with some sort of PFAS additives.
  - AlgorithmicTime 5y ago
    I don't think PFAS are for moisture wicking. More water/moisture repelling. Also, go to Costco and there's a 3 or 4 pack of 100% cotton boxer-briefs on sale.
  - dd36 5y ago
    Me too but for undershirts! I didn’t see your comment before making mine.
  - ashildr 5y ago
    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.)
    - strict9 5y ago
      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).

chamsom 5y ago

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 and we don't know what those do either. Here's what you can do: 1. Open windows to your house, but also your car which contains PFAS in the upholstery 2. Minimize dust w/ vacuum, HEPA filters 3. Reduce use of old couches which stirs up dust until you replace it 4. Minimize polyurethane foam products - polyster foam is better 5. Paper/biodegradable takeout containers and fast food packaging have PFAS lined so the paper doesn't absorb oil etc.

l30n4da5 5y ago
> HEPA filters This is probably the most important. If you work from home, it might be prudent to at least have a one-room HEPA filter in your home office.
- intrasight 5y ago
  I have in furnance airflow and also one in bedroom.
  - barbazoo 5y ago
    I'm having trouble figuring out what kind of filter I can use for my furnace. I've read a little bit about it and it seems that a residential furnace might not be able to handle the HEPA filter due to the higher airflow resistance. Even MERV 13 might already be too high.
    - bradfa 5y ago
      The MERV or other rating of a filter is not what's important to your furnace (it's what's important to the humans) but what matters is how much airflow through the filter can be achieved by the furnace fan and how much pressure drop the filter induces. If you get a MERV 12 filter with LOTS of filter material, it may flow more air at a lower pressure drop than a MERV 6 filter with minimal filter material. Look for more pleats in the filter or modify (or hire an HVAC contractor to modify) your furnace filter cabinet to accept a thicker filter cartridge. For reference, in my furnace during an HVAC consultation, we saw the same 0.5 inches of water pressure drop from a cheap 3M Filtrete MERV 7 filter as with a K&N reusable MERV 12 filter. The K&N has MUCH more filter material. You don't want to restrict the airflow to your furnace any more than is necessary. Most furnaces will have their required maximum pressure drop from the duct work and filter printed on a label inside. You can get a differential pressure meter to measure the actual pressure drops yourself, or hire an HVAC technician to do an audit of your furnace (often they'll do lots of other neat tests and give you lots of data and reports and info, too).

doitLP 5y ago

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, etc) many of which had even worse safety profiles, while proudly proclaiming their products were "BPA free". 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.

ashildr 5y ago
> from "safe until proven otherwise" to "unsafe until (independently) proven safe" That’s about how the EU does it.
- ironmagma 5y ago
  How can you prove anything safe without data on its use? Isn't that sort of a chicken and egg problem?
  - sooheon 5y ago
    Should the data be collected without consent by exposing the public to it for decades or provided by clinical trials funded by the company that wants to bring it to market?
    - qweqwweqwe-90i 5y ago
      You are asking for the impossible. It can be impossible to tell with things that only have no - to mild effects. Proving a negative ("this is not dangerous") is hard :)
      - sooheon 5y ago

forgotmypw17 5y ago

,,cleaning,, products, even dish and hand soap new furniture and clothes any sort of spray or solvent ... read the ingredients if available avoid if it smells synthetic avoid places where you encounter them ... edit: for the downvoters, try googling "indoor air pollution voc" example: https://www.bbc.com/future/article/20200909-why-indoor-air-pollution-is-an-overlooked-problem https://www.bbc.com/future/article/20200909-why-indoor-air-p...

ffhhj 5y ago

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?

camgunz 5y ago
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-perfluorooctanoic-acid-pfoa.html https://www.cancer.org/cancer/cancer-causes/teflon-and-perfl... [2]: https://www.healthline.com/health/body-modification/is-silicone-toxic#symptoms https://www.healthline.com/health/body-modification/is-silic...
- deleted 5y ago
  [deleted]
calvinmorrison 5y ago
Rubber?

magwa101 5y ago

Do HEPA filters capture PFAS particles?

cjlars 5y ago

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 gallon drum of activated carbon to do anything on the chemical front. A quick solution is to crack the windows, or if you live in a non-temperate climate, install an energy recovery ventilating system.

bumby 5y ago
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 intake. That's why many designs (e.g., heat recovery wheels) are generally banned in some applications like healthcare. With the crowd that HN attracts, I'd be interested if anybody has implemented some sort of demand-control ventilation in their home.
- cjlars 5y ago
  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 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.