9 ms·

Biodegradable or not means much less than it sounds like, if micro- and nano- plastics still bioaccumulate in animals disrupting their endocrinology

throwawayboise 5y ago
Biodegrade does not mean "chew up into tiny pieces" it means chemically break down. Biodegraded plastic would end up being much simpler molecules, probably CO2 and methane mostly.
mlyle 5y ago
> Biodegradable or not means much less than it sounds like Long-term stability of plastics means that the problems from microplastics today could still be problems in a million years. It's worse than nuclear waste in that regard: at least the hottest isotopes degrade quickly and the less hot still halve on a predictable schedule. Currently, for a lot of plastics, all you've got removing them from circultion are UV degradation and weathering processes, along with processes burying them in sediments for unknown periods. But the microbial environment could at least confine this to be a very bad problem for our time, instead of forever.
- hanniabu 5y ago
  Companies will just create bacteria resistant plastic and continue to fuck us
  - freemint 5y ago
    And nature (maybe with our hand) will catch up. It's playing cat and mouse with a mouse that stands still once the plastic is produced.
  - trulyme 5y ago
    "and continue to provide what we want", you mean? It's not the companies that are the (sole) problem.
    - soperj 5y ago
      I don't know. For a while the major toothpaste companies were putting plastic beads in toothpaste as grit. I would say that's a company issue.
      - heurisko 5y ago
        It's the 21st century version of lead in makeup. I'm certain in 100-150 years it will be viewed in the same way. https://en.m.wikipedia.org/wiki/Victorian-era_cosmetics https://en.m.wikipedia.org/wiki/Victorian-era_cosmetics
    - hackarimoo 5y ago
      The problem is the system. You can expect one or two persons to act rational, but at the scale of 100s, 1000s, millions, it's just crowd dynamics following statistical processes, just as the market itself is. If we want anything to change, we need systemic changes to what behavior is incentivized by the world we live in - and I can not think of anything that would do the job other than abolishing or at least heavily restraining capitalism.
dclowd9901 5y ago
It is with complete ignorance that I'm asking this, but isn't it the case that, at a molecular level, plastics are just like any other material? That they can be broken down to such a point that their molecular composition no longer matters, and they are, once again, "raw" molecules by which other things (even living things) can be composed? What does "accumulation" even mean in that context?
- mlyle 5y ago
  Anything can be broken down, but many things are effectively stable in the environment-- including in organisms-- for nearly forever, because nothing breaks them down or the rate of degradation is low enough that it doesn't matter. What I believe he's saying is: even if it looks like bacteria may eventually begin to chip away at the microplastics problem, we still face the prospect of having them accumulate for decades or longer in bigger lifeforms and cause problems. (But at least today's plastic releases wouldn't be a problem forever). That is, this improves the situation greatly but doesn't remove any of the nearer term suck.
  - politician 5y ago
    On long enough time scales, the all of the plastic on Earth will be incinerated, regardless of whether microbes evolve to make use of it sooner.
  - ars 5y ago
    > we still face the prospect of having them accumulate for decades or longer in bigger lifeforms and cause problems. That's not really accurate - if an organism can breakdown (digest) plastic to any extent, it can do so all the way to water and CO2. There are a few exceptions: Teflon and PVC are the main ones, but most plastic is pretty simple, and once digested it will not accumulate.
    - mlyle 5y ago
      > That's not really accurate - if an organism can breakdown (digest) plastic to any extent, it can do so all the way to water and CO2. I can't breakdown most plastic to any significant extent. If I ate small pieces of plastic, some would be excreted in poop and some would accumulate in my body. If I ate animals that have eaten small pieces of plastic, being high up the foodchain, this may be exacerbated (biomagnification). If bacteria learn to degrade plastic--- that may improve the situation for my grandchildren but it probably doesn't reduce how much is accumulating in marine life now that much.
ch4s3 5y ago
Single celled organisms don't have endocrine systems, if they are able to break plastics down and metabolize them, then that's the end of those big thorny molecules.

throwawayboise 5y ago

Biodegrade does not mean "chew up into tiny pieces" it means chemically break down. Biodegraded plastic would end up being much simpler molecules, probably CO2 and methane mostly.

mlyle 5y ago

> Biodegradable or not means much less than it sounds like Long-term stability of plastics means that the problems from microplastics today could still be problems in a million years. It's worse than nuclear waste in that regard: at least the hottest isotopes degrade quickly and the less hot still halve on a predictable schedule. Currently, for a lot of plastics, all you've got removing them from circultion are UV degradation and weathering processes, along with processes burying them in sediments for unknown periods. But the microbial environment could at least confine this to be a very bad problem for our time, instead of forever.

hanniabu 5y ago
Companies will just create bacteria resistant plastic and continue to fuck us
- freemint 5y ago
  And nature (maybe with our hand) will catch up. It's playing cat and mouse with a mouse that stands still once the plastic is produced.
- trulyme 5y ago
  "and continue to provide what we want", you mean? It's not the companies that are the (sole) problem.
  - soperj 5y ago
    I don't know. For a while the major toothpaste companies were putting plastic beads in toothpaste as grit. I would say that's a company issue.
    - heurisko 5y ago
      It's the 21st century version of lead in makeup. I'm certain in 100-150 years it will be viewed in the same way. https://en.m.wikipedia.org/wiki/Victorian-era_cosmetics https://en.m.wikipedia.org/wiki/Victorian-era_cosmetics
  - hackarimoo 5y ago
    The problem is the system. You can expect one or two persons to act rational, but at the scale of 100s, 1000s, millions, it's just crowd dynamics following statistical processes, just as the market itself is. If we want anything to change, we need systemic changes to what behavior is incentivized by the world we live in - and I can not think of anything that would do the job other than abolishing or at least heavily restraining capitalism.

dclowd9901 5y ago

It is with complete ignorance that I'm asking this, but isn't it the case that, at a molecular level, plastics are just like any other material? That they can be broken down to such a point that their molecular composition no longer matters, and they are, once again, "raw" molecules by which other things (even living things) can be composed? What does "accumulation" even mean in that context?

mlyle 5y ago
Anything can be broken down, but many things are effectively stable in the environment-- including in organisms-- for nearly forever, because nothing breaks them down or the rate of degradation is low enough that it doesn't matter. What I believe he's saying is: even if it looks like bacteria may eventually begin to chip away at the microplastics problem, we still face the prospect of having them accumulate for decades or longer in bigger lifeforms and cause problems. (But at least today's plastic releases wouldn't be a problem forever). That is, this improves the situation greatly but doesn't remove any of the nearer term suck.
- politician 5y ago
  On long enough time scales, the all of the plastic on Earth will be incinerated, regardless of whether microbes evolve to make use of it sooner.
- ars 5y ago
  > we still face the prospect of having them accumulate for decades or longer in bigger lifeforms and cause problems. That's not really accurate - if an organism can breakdown (digest) plastic to any extent, it can do so all the way to water and CO2. There are a few exceptions: Teflon and PVC are the main ones, but most plastic is pretty simple, and once digested it will not accumulate.
  - mlyle 5y ago
    > That's not really accurate - if an organism can breakdown (digest) plastic to any extent, it can do so all the way to water and CO2. I can't breakdown most plastic to any significant extent. If I ate small pieces of plastic, some would be excreted in poop and some would accumulate in my body. If I ate animals that have eaten small pieces of plastic, being high up the foodchain, this may be exacerbated (biomagnification). If bacteria learn to degrade plastic--- that may improve the situation for my grandchildren but it probably doesn't reduce how much is accumulating in marine life now that much.

ch4s3 5y ago

Single celled organisms don't have endocrine systems, if they are able to break plastics down and metabolize them, then that's the end of those big thorny molecules.