3 ms·

Does this mean I shouldn't be doing my dishes with hot water?

by jzelinskie 3y ago

lotsofpulp 3y ago
I assume if you have a newer house with PVC or PEX piping, this is not a concern.
- doubled112 3y ago
  Should we worry about plastics instead?
  - stephen_g 3y ago
    PEX (and polyethylene in general) is one of the least concerning plastics, it’s not worth worrying about on that front. (I wouldn’t want to drink out of PVC though since it often contains phthalates as a plasticiser).
    - exmadscientist 3y ago
      Rigid PVC has few if any plasticizers. (This makes sense: it isn't very plastic!) This is the type usually used for water pipe, at least around here. It's probably not very dangerous. Flexible PVC is nasty.
  - lazide 3y ago
    Almost certainly, though most of the problematic plasticizers (anecdotally) probably work themselves out in the first couple years. We likely won't see any real studies on it for awhile though, but [https://www.sciencedirect.com/science/article/abs/pii/S004896972101442X https://www.sciencedirect.com/science/article/abs/pii/S00489...] is concerning. "In the US, PEX pipe manufacturers often request a pipe to be certified in accordance with the NSF International/ANSI 61 Standard leaching procedure (NSF International, 1988). However, the results are not made public and the water that contacts the pipe for its first 90 days is discarded and not tested. Therefore, there is a general lack of available data to be used for an LCA on US PEX pipe products." Water in plastic pipes is pretty stanky at first, especially the first couple months/weeks. PEX has issues with permeability - it's highly oxygen and chemical permeable. Also contaminants from manufacture working themselves out. PVC has a lot of plasticizers and stabilizers, and warmer temps make it leach faster. Many of them endocrine disruptors. That said, no such thing as a free lunch. And as long as the water is kept moving, chances are it's fine after awhile. Avoid the 'stanky water fountain' effect by letting the water run a bit before drinking/using it if you're worried.
    - SoftTalker 3y ago
      > Water in plastic pipes is pretty stanky at first, especially the first couple months/weeks. This is mostly from the glue used at the pipe joints, which has a lot of volatile components.
      - lazide 3y ago
        unfortunately not, the pipes themselves are also an issue. PEX doesn’t use any glue, and all 62 distinct chemical compounds identified in that paper I linked came straight from the pipes themselves. PVC is even worse in my experience.
  - rdtsc 3y ago
    I remember that one of the plumbers or house inspectors recommended plastic pipes to us and I thought the same thing: lead solder or plastic leaching into the water.
- ericcumbee 3y ago
  this is more about the distribution lines running to houses than the plumbing in the house.
  - oooyay 3y ago
    There are no safe levels of lead exposure and there plenty of homes with lead piping as well as lead service lines: https://www.nrdc.org/resources/lead-pipes-are-widespread-and-used-every-state https://www.nrdc.org/resources/lead-pipes-are-widespread-and...
BurningFrog 3y ago
I really doubt any relevant amounts remain on the cleaned dishes. If you drink the dish water OTOH...

Does this mean I shouldn't be doing my dishes with hot water?

lotsofpulp 3y ago

I assume if you have a newer house with PVC or PEX piping, this is not a concern.

doubled112 3y ago
Should we worry about plastics instead?
- stephen_g 3y ago
  PEX (and polyethylene in general) is one of the least concerning plastics, it’s not worth worrying about on that front. (I wouldn’t want to drink out of PVC though since it often contains phthalates as a plasticiser).
  - exmadscientist 3y ago
    Rigid PVC has few if any plasticizers. (This makes sense: it isn't very plastic!) This is the type usually used for water pipe, at least around here. It's probably not very dangerous. Flexible PVC is nasty.
- lazide 3y ago
  Almost certainly, though most of the problematic plasticizers (anecdotally) probably work themselves out in the first couple years. We likely won't see any real studies on it for awhile though, but [https://www.sciencedirect.com/science/article/abs/pii/S004896972101442X https://www.sciencedirect.com/science/article/abs/pii/S00489...] is concerning. "In the US, PEX pipe manufacturers often request a pipe to be certified in accordance with the NSF International/ANSI 61 Standard leaching procedure (NSF International, 1988). However, the results are not made public and the water that contacts the pipe for its first 90 days is discarded and not tested. Therefore, there is a general lack of available data to be used for an LCA on US PEX pipe products." Water in plastic pipes is pretty stanky at first, especially the first couple months/weeks. PEX has issues with permeability - it's highly oxygen and chemical permeable. Also contaminants from manufacture working themselves out. PVC has a lot of plasticizers and stabilizers, and warmer temps make it leach faster. Many of them endocrine disruptors. That said, no such thing as a free lunch. And as long as the water is kept moving, chances are it's fine after awhile. Avoid the 'stanky water fountain' effect by letting the water run a bit before drinking/using it if you're worried.
  - SoftTalker 3y ago
    > Water in plastic pipes is pretty stanky at first, especially the first couple months/weeks. This is mostly from the glue used at the pipe joints, which has a lot of volatile components.
    - lazide 3y ago
      unfortunately not, the pipes themselves are also an issue. PEX doesn’t use any glue, and all 62 distinct chemical compounds identified in that paper I linked came straight from the pipes themselves. PVC is even worse in my experience.
- rdtsc 3y ago
  I remember that one of the plumbers or house inspectors recommended plastic pipes to us and I thought the same thing: lead solder or plastic leaching into the water.
ericcumbee 3y ago
this is more about the distribution lines running to houses than the plumbing in the house.
- oooyay 3y ago
  There are no safe levels of lead exposure and there plenty of homes with lead piping as well as lead service lines: https://www.nrdc.org/resources/lead-pipes-are-widespread-and-used-every-state https://www.nrdc.org/resources/lead-pipes-are-widespread-and...

BurningFrog 3y ago

I really doubt any relevant amounts remain on the cleaned dishes. If you drink the dish water OTOH...