A better reason to recycle plastics?

[Jarhyn]

Not too long ago, a friend of mine posted a thing on Facebook saying that plastic should be recycled because it'll just stay in a landfill forever if we do not. In other places, I've seen it said that 'who cares, it's cheaper and easier to make new rather than recycle.

But looking at both, a thought hit me: evolution doesn't care. Plastic burns hot, sooty, and for a long time. There's a lot of chemical energy in most plastics, and that means that something, eventually, will evolve to eat them. Then I thought of the applications we use plastics for. Sure, they're used for disposables because plastics are generally cheap, but they're also used for structure, piping, insulation, and a lot of other applications that are expected to last decades, if not centuries. The more evolvers are exposed to plastics, the more opportunity that one which happens to have a mutation to eat them will have the opportunity to succeed with that evolution. Landfills expose a lot of plastic to a lot of bacteria. Ergo, throwing plastic away isn't viable, not because it doesn't biodegrade, but rather because we can't afford to let it START biodegrading. It is not it's expensiveness which should drive us to recycle, but the expensiveness of losing the ability to count on plastics AT ALL.

Thoughts?

 

[skepticalbip]

A few thoughts:

There are several different kinds of plastic. A plastic that is useful for one application is not for other applications.

Some plastics are designed to biodegrade. The plastic used for milk jugs springs to mind.

There is already bacteria that consume plastic.

ETA:
One final thought:

Anything that doesn't breakdown and biodegrade is no problem for the environment except that it takes up space in the landfill. It is the things that do break down that cause environmental problems like some of the chemicals released when breaking down leaching into the groundwater or escaping into the atmosphere.

 

[Kharakov]

The plastic eating bacteria apocalypse. I've thought about it in the past. However, moisture and other things are generally needed for bacteria to consume whatever they like munching on. Check out this article on nature.com (googled plastic eating bacteria):
[h=1]Marine microbes digest plastic[/h]

 

[Jarhyn]

Simply put, the septic stack in the house I'm buying is mostly plastic. PVC or the similar. It'd suck if that started to actually rot.

 

[rjh01]

One problem with plastic is that some animals do eat it. However they cannot use the energy from it and it builds up in their stomach. This is not good for the animals. This is another good reason to reduce plastic bags and other plastics.

 

[Jarhyn]

That's a pity for the animals, but I'm talking reasons which don't assume the animal's death actually matters. Imagine how destructive that animal will be should it gain gut flora which allow it to gain energy from the plastics it eats. Then it'll stop being a minor pest with the occasional dead specimen, but instead, a blight on our entire species .

 

[Kharakov]

Simply put, the septic stack in the house I'm buying is mostly plastic. PVC or the similar. It'd suck if that started to actually rot.

 Polyvinyl_chloride#Degradation

 

[Jimmy Higgins]

How is recycling plastic going to stop that? There is already a ton of it in the environment, either as refuse or in use for the evolved plastic eating beaver to destroy the world.

 

[Kharakov]

 

[doubtingt]

How is recycling plastic going to stop that? There is already a ton of it in the environment, either as refuse or in use for the evolved plastic eating beaver to destroy the world.

Evolution is about probabilities, which in this case is about the number of molecules of plastic that are in contact with existing bacteria that could produce a random mutation that happens to consume plastic and cause that bacteria to proliferate. Whatever the current probability is of such an evolutionary adaption, that probability will basically double if the number of molecules of plastic in contact with bacteria doubles. So, every new gram of plastic produced increases the probability that such an evolution would occur. That means the every gram of plastic recycled and thus replacing the gram that would have otherwise been produced "from scratch" prevents that increase in probability. In addition, I think (though not sure) that there are many times more bacteria cells in soil than just about anywhere else that plastics are used. Thus, throwing plastics into landfills puts more plastic into contact with potentially evolving bacteria than most ways in which plastics are used. So, that is another way that putting a piece of plastic back into use rather than in the soil reduces the probability of a plastic eating bacteria that goes beyond any that currently exist and could pose a serious threat to their current functions they serve for us.

 

[Elixir]

How is recycling plastic going to stop that? There is already a ton of it in the environment, either as refuse or in use for the evolved plastic eating beaver to destroy the world.

Evolution is about probabilities, which in this case is about the number of molecules of plastic that are in contact with existing bacteria that could produce a random mutation that happens to consume plastic and cause that bacteria to proliferate. Whatever the current probability is of such an evolutionary adaption, that probability will basically double if the number of molecules of plastic in contact with bacteria doubles. So, every new gram of plastic produced increases the probability that such an evolution would occur. That means the every gram of plastic recycled and thus replacing the gram that would have otherwise been produced "from scratch" prevents that increase in probability. In addition, I think (though not sure) that there are many times more bacteria cells in soil than just about anywhere else that plastics are used. Thus, throwing plastics into landfills puts more plastic into contact with potentially evolving bacteria than most ways in which plastics are used. So, that is another way that putting a piece of plastic back into use rather than in the soil reduces the probability of a plastic eating bacteria that goes beyond any that currently exist and could pose a serious threat to their current functions they serve for us.

I'm predicting ocean-spawned plasticophiles. Landfill is too static to fulfill as many of the possibilities that could arise from contact. An unfortunate bit of plastic can drift around in the ocean for years, experiencing a level of diverse contacts (and sequences of contact) that its landfill-dwelling brethren could only dream about.

 

[doubtingt]

Evolution is about probabilities, which in this case is about the number of molecules of plastic that are in contact with existing bacteria that could produce a random mutation that happens to consume plastic and cause that bacteria to proliferate. Whatever the current probability is of such an evolutionary adaption, that probability will basically double if the number of molecules of plastic in contact with bacteria doubles. So, every new gram of plastic produced increases the probability that such an evolution would occur. That means the every gram of plastic recycled and thus replacing the gram that would have otherwise been produced "from scratch" prevents that increase in probability. In addition, I think (though not sure) that there are many times more bacteria cells in soil than just about anywhere else that plastics are used. Thus, throwing plastics into landfills puts more plastic into contact with potentially evolving bacteria than most ways in which plastics are used. So, that is another way that putting a piece of plastic back into use rather than in the soil reduces the probability of a plastic eating bacteria that goes beyond any that currently exist and could pose a serious threat to their current functions they serve for us.

I'm predicting ocean-spawned plasticophiles. Landfill is too static to fulfill as many of the possibilities that could arise from contact. An unfortunate bit of plastic can drift around in the ocean for years, experiencing a level of diverse contacts (and sequences of contact) that its landfill-dwelling brethren could only dream about.

But there are about 40 times as many bacteria cells in a gram of soil than a gram of ocean water. Also, there is millions of times more plastic contacting soil than in the ocean.

 

[bilby]

If this is a risk, then it is too late to prevent it; there is enough plastic unrecoverably exposed to the environment that we cannot fix the problem, and increased recycling efforts are futile.

Even if we could recover all the waste plastic in the environment, including in landfills, and recycle it, the problem still wouldn't go away - that PVC septic pipe is itself an environment where such a problematic bacterium could evolve - what should we do to prevent that? Perhaps we could wrap all buried plastic pipes in steel, to protect them from bacteria; and then put a layer of plastic over the steel to protect it from corrosion, and then...

Anyway, the cost of un-recycled plastics is a possible future risk of bacterial erosion of useful plastic parts; but the benefit is immediate and lasting - plastics that are landfilled and never break down are a good way to sequester carbon. I would rather all the world's coal and oil ended up as solid, non-biodegradable plastic in landfill for eternity, than it ended up in the atmosphere as greenhouse gasses.

 

[Kharakov]

I'm predicting ocean-spawned plasticophiles. Landfill is too static to fulfill as many of the possibilities that could arise from contact. An unfortunate bit of plastic can drift around in the ocean for years, experiencing a level of diverse contacts (and sequences of contact) that its landfill-dwelling brethren could only dream about.

But there are about 40 times as many bacteria cells in a gram of soil than a gram of ocean water. Also, there is millions of times more plastic contacting soil than in the ocean.

There are some articles on ocean species of diatoms and bacteria munching on plastic.

There are a couple of fungus, yeast, or lichen land based species that munch on plastics too. You just have to consider that plastic is a totally new food source, and it is going to take more than 60 years for the kids to start liking it.

First article is interesting.

http://www.abc.net.au/environment/articles/2013/11/13/3888603.htm

It's on IO9 as well..

 plastisphere

http://www.nature.com/news/2011/110328/full/news.2011.191.html

 Nylon eating bacteria

 

[doubtingt]

If this is a risk, then it is too late to prevent it; there is enough plastic unrecoverably exposed to the environment that we cannot fix the problem, and increased recycling efforts are futile.

Even if we could recover all the waste plastic in the environment, including in landfills, and recycle it, the problem still wouldn't go away - that PVC septic pipe is itself an environment where such a problematic bacterium could evolve - what should we do to prevent that? Perhaps we could wrap all buried plastic pipes in steel, to protect them from bacteria; and then put a layer of plastic over the steel to protect it from corrosion, and then...

Anyway, the cost of un-recycled plastics is a possible future risk of bacterial erosion of useful plastic parts; but the benefit is immediate and lasting - plastics that are landfilled and never break down are a good way to sequester carbon. I would rather all the world's coal and oil ended up as solid, non-biodegradable plastic in landfill for eternity, than it ended up in the atmosphere as greenhouse gasses.

Read my prior post.

Every ounce of plastic recycled, reduces the probability of this happening. The mutation that could make plastic a highly effective source of energy for a bacteria will occur randomly. If there is no plastic in contact with the bacteria cells that randomly produce this mutation, then it will not take hold. Thus, the probability that such a mutation will take hold is directly a function of the sheer mass of plastic in contact with bacteria (which disproportionately lives in the soil).

Getting into a deadly car accident requires that you are in car, but just because you already do that sometimes doesn't guarantee that you will get into a deadly accident. If you double the amount of time you are in a car and you drive in the most high traffic areas, then your odds greatly increase.

 

[bilby]

If this is a risk, then it is too late to prevent it; there is enough plastic unrecoverably exposed to the environment that we cannot fix the problem, and increased recycling efforts are futile.

Even if we could recover all the waste plastic in the environment, including in landfills, and recycle it, the problem still wouldn't go away - that PVC septic pipe is itself an environment where such a problematic bacterium could evolve - what should we do to prevent that? Perhaps we could wrap all buried plastic pipes in steel, to protect them from bacteria; and then put a layer of plastic over the steel to protect it from corrosion, and then...

Anyway, the cost of un-recycled plastics is a possible future risk of bacterial erosion of useful plastic parts; but the benefit is immediate and lasting - plastics that are landfilled and never break down are a good way to sequester carbon. I would rather all the world's coal and oil ended up as solid, non-biodegradable plastic in landfill for eternity, than it ended up in the atmosphere as greenhouse gasses.

Read my prior post.

Every ounce of plastic recycled, reduces the probability of this happening. The mutation that could make plastic a highly effective source of energy for a bacteria will occur randomly. If there is no plastic in contact with the bacteria cells that randomly produce this mutation, then it will not take hold. Thus, the probability that such a mutation will take hold is directly a function of the sheer mass of plastic in contact with bacteria (which disproportionately lives in the soil).

Getting into a deadly car accident requires that you are in car, but just because you already do that sometimes doesn't guarantee that you will get into a deadly accident. If you double the amount of time you are in a car and you drive in the most high traffic areas, then your odds greatly increase.

I did read your post. I disagree with your assumption that delaying the issue is worthwhile.

Evolution has literally all the time in the world.

If it can happen, eventually it will, no matter what steps you try to take to delay it.

Delaying the problem for centuries, or even millennia, won't change a thing about the scale of the problem if and when it does arise.

Fortunately, as we can see from our experience with materials that do degrade over time, degradability does not render things totally useless. Most of my house is made from timber; while this does mean it needs protection from the environment and occasional replacement of degraded parts, it is far from being the end of the world. And in these parts, it's not just bacteria and moulds that eat houses - we have termites too. And yet my house still stands, decades after it was built.

Even plastic parts need inspection, repair and replacement from time to time. If plastic could rot, that would need to be more frequent. But that's not a big deal. Humans have a lot of experience of making things work with degradable parts. There is no reason why our civilisation must have non-degradable materials to survive and thrive - we are fortunate to be able to take advantage of them for the last few decades, but non-biodegradability is not the great essential characteristic that you seem to imagine it to be.