As long as the plastic is not subjected to high heat or pressure, their "passive" use should not impact plant health (or your own). I would be more concerned about the plastics you use every day, such as the pour spout in your Coffee Maker, where heat can leach out bad things. Trash bag liners in your container should not be a worry. Raybo

I received my order of UV-resistant green sandbags produced by DeWitt. I thought that it would be the same polypropylene fabric that they use as a weed barrier; but I now doubt it. In other words, I expected a small hole (for water drainage) at each cross weave (the "thread" is about 1/8 to 1/12 wide, flat, and thin). Water drains quite well through the stitching at the bottom of the bag. In contrast, drainage from the fabric wall is slow. Water leakage through the fabric is best observed if a jet of water from the hose is aimed at the wall; otherwise, leakage from the wall only by gravity is slow and rare. I can't tell if the fabric has a thin film laminated coating. The surface of the fabric is smoother than I expected if there was no lamination, but more water drains out than I expected if there was a laminated coating. In no way is any possible laminated coating present on the DeWitt bag similar to that pictured for the long lasting sandbags offered by Dayton Bag Company. Making pots out of these sandbags would involve folding the bottom, and securing such folds with a few dabs hot melted glue. These would be loose folds to form a more cylindrical bottom, just strong enough to make it easier to fill the bags with dirt. UV-resistant hot glue sticks are available (I don't know where), but since these will be in the bottom of the bag, shielded from UV by dirt, sticks from the Craft section of Wal-Mart should be fine. Since such pots would be too tall given their diameter, the tops could be rolled inside out, to reduce the height. I'll go ahead and make some pots out of a few of these, since I got them anyway. But I can't really recommend them at this point: First, I doubt that any pinholes in the fabric are large enough to cause roots to branch. Second, I don't think that the oxygen diffusion rate through the bag would be that much better than a solid plastic pot. I previously suspected the first, but I was really hoping for a much improved oxygen situation. If you are currently a user of pots made from black plastic film (these have holes in the bottom, otherwise they are similar to normal plastic bags, except that they are sold as nursery pots); these DeWitt sandbags may be competitive. It is possible that if I subjected these sandbags to a small amount of wear and tear (as a transport bag), the fabric will loosen up and become more porous for oxygen. In which case, I would post an update. Here is a link that might be useful: DeWitt Sandbags

There is a fast growing industry in collecting and composting organic waste, especially food scrap. So bagged compost is not just going to be manure anymore, it's yard trimmings, tree limbs and food scrap. Some contamination is inevitable. Lots of the food scrap haulers use compostable can liners, but not all, so you may find bits of plastic now and then. Plastic itself is merely a nuisance in the garden, not a toxic problem. If you're concerned about what else goes in, keep bugging the producer and ask them what their inputs are.

it is winter time now. i wonder if i can cover it with a plastic bag, and leave it outside? i am here in the southern california.