I'm really into 3D printing and have studied all sorts of plastics as part of my research into making perfect prints for various objects. One thing that astound

I'm really into 3D printing and have studied all sorts of plastics as part of my research into making perfect prints for various objects. One thing that astounds me is the complete lack of information/disclosure requirements by plastic pellet manufacturers and filament manufacturers. They can basically put whatever the fuck they want in these batches and never have to tell anyone about it other than provide the safety sheet (MSDS) which tells you very little about the actual properties of these materials. Let alone their lifetimes! For example, Polylactic Acid (PLA) is the most popular type of filament for 3D printing. It's made from (the non-edible parts of) corn (and other plants) and is considered "eco friendly" but this isn't entirely certain! In order to actually break down into harmless components PLA needs to be eaten by one of two species of bacteria. These bacteria only live in soil. As in, they don't exist in the ocean. Having said that, there's been no studies of PLA in ocean water! So we don't really know how long it will take or even if PLA will break down if it ends up in the ocean. Not only that but there's all sorts of additives being added to PLA that make it less likely to break down. Things like UV stabilizers and who-knows-what substances that increase its melting point and/or shrinkage/warping during heat-treatment/annealing. I suspect that PLA is indeed much better for the environment and will break down safely and reasonably quickly in the ocean but there's no data to back this up and it drives me nuts! I can't say that it's much better than, say, PET(G) or Polypropylene with no research to back up such a claim. Why do I think it's probably better? Because the hydrocarbon chains that make up PLA are shorter than traditional plastics. Shorter chains are easier to break and we know that once broken (down) PLA becomes a harmless charcoal-like substance (and water and a bit of CO2 after bacteria finalize their digestion). This same process is likely to occur over time all by itself thanks to UV degredation from the sun but if UV stabilizers are added to the PLA does that mean it will behave similarly to ABS, PET, and PP when it winds up in the ocean? Let's hope that it doesn't!