They're specifically sold on the basis that they don't leach into the soil - that's why they're used in organic farms/orchards.
(Although, after 50 years, who know what might happen).
It seems to me that with plastics we've been told they're safe and inert and yet have repeatedly been proven not to be (latest stuff about PFAS comes to mind.)
I'm not sure I would trust plastics exposed to the elements for 50 years to not have _something_ occur to them. There's just way too much chemistry that can happen when you're in contact with water and sunlight for such long periods of time.
Of course they claim there is no leeching: there is no way to prove it ex ante so even if the claim is false it will be decades before any downside to making the claim arises.
As the other commenter notes, this is pretty common among new chemical products.
"There is no harm" -> "The harm is marginal" -> "The harm is manageable" -> "Remediation is too expensive for the private sector, the government needs to fund the fix"
I'm sure they do - wear and tear to anything outdoors is inevitable (except maybe if your fence is titanium, in which case the wear and tear probably amounts to individual electrons!) but I would still very much prefer that those plastic bags be put to use rather than decompose - at broadly the same rate - uselessly in a landfill site.
> but I would still very much prefer that those plastic bags be put to use rather than decompose - at broadly the same rate - uselessly in a landfill site.
Well, to be honest, if the landfill is properly managed, protected from leaching into the water table, I would personally prefer those plastic bags to be exactly there -- in the landfill. If they're going to break down, I would rather have everything be concentrated in a single area rather than in thousands of fence posts near farms and ranches. We definitely should find ways to reuse those materials, but not at the cost of diffusely polluting things.
I agree. Landfill has been demonized as a solution to plastic waste but is likely optimal. If stuff is in landfill we can just leave it there until better recycling tech becomes available. Problems like plastic leeching are ignored by recycling proponents because it is a hard problem to measure, so it is more convenient to ignore.
