[omnicognate]

Glass is awesome. It's reusable many times over and recyclable after that. We used to have systems to allow that reuse (bottle return) before somehow we ended up throwing away a plastic bottle (recycled at best) every time we buy a pint of milk.

And contrary to sibling comment, glass containers don't leach heavy metals (or anything else) into food.

[jdietrich]

Plastic bottles are more environmentally friendly.

Glass requires massively more energy to manufacture, even using 100% recycled glass. Glass is heavy, so it's more expensive to transport. Collecting and washing bottles for re-use consumes a substantial amount of energy, which greatly increases the number of trips required to break even on the higher manufacturing impacts. The lifespan of a re-usable glass bottle is relatively very short, because glass is fragile. Glass compares poorly to HDPE when we factor in a realistic lifespan for glass and a realistic recycling rate for HDPE.

[omnicognate]

They are currently, but only because we're crap at reuse. Glass bottles are highly reusable - 15 times or more on average - before they need to be recycled (i.e. melted).

Minimising the transport costs is part of the design of the reuse process. Milk floats are a great example of this. Milk delivered to the door by an electrical vehicle daily and empties collected by the same vehicle, washed and refilled. This was the standard way to get milk (and often juice, eggs, etc) in my childhood but nowadays people throw a plastic bottle into a generic recycling stream every time and I highly doubt it's an improvement.

Online grocery shopping reduces fuel usage and pollution for getting goods to homes by consolidating many deliveries in one vehicle round. It would be great to see this being used (again) as a way of improving packaging efficiency too, one way or another.

[doubleg72]

I think microplastics are a much greater concern than the extra energy used to transport either of these materials.

[sneak]

It's much heavier to cart around, which must be factored in. There's absolutely nothing inherently harmful in single use plastics if they get properly disposed of in landfill.

Driving heavy glass back and forth from the bottling plant burns a lot of diesel unnecessarily.

[morsch]

In either case it's better not to transport bulk liquids more than necessary. Tap water, locally brewed beer.

[devoutsalsa]

To "recycle" glass, all you have to do is wash it.

[morsch]

That's what the grandparent sensibly referred to as reuse; you can do that, but you after you're done reusing it, you can also recycle it, that is, melt it down and make new glass from it.