Some single-stream systems have stopped taking glass. Paper/cardboard seems to be cost-effective so there isn't a real pressure to remove that. If anything it's

Some single-stream systems have stopped taking glass. Paper/cardboard seems to be cost-effective so there isn't a real pressure to remove that. If anything it's one of the few things (along with metal) that the recycling systems actually get decent recovery rates from. The reasons for removing glass in particular seem to be: 1) it's the heaviest component, so removing it decreases transportation/processing costs, 2) after China stopped accepting exported glass, there's a lack of processors who will take it, and 3) broken glass shards contaminate more valuable things in the stream, plus damage machinery. Plastic isn't really cost-effective either and has low recovery rates, but it's at least lighter than glass and doesn't break into shards as easily, so a lot of places still take it, if only to make people feel good. Links: https://wamu.org/story/19/04/26/arlington-ends-curbside-glass-recycling/ https://wamu.org/story/19/04/26/arlington-ends-curbside-glas..., https://www.fairfaxcounty.gov/news2/glass-containers-no-longer-required-in-curbside-recycling-program/ https://www.fairfaxcounty.gov/news2/glass-containers-no-long..., https://www.recyclingtoday.com/article/recycling-programs-phase-out-glass-2018/ https://www.recyclingtoday.com/article/recycling-programs-ph...