It’s always best to reuse, recycle, or compost when possible. However, some waste will inevitably end up in landfills. Landfills are designed to prevent biodegradation, because when materials do degrade in them, they produce more methane. Because of this, recycled plastic is the more sustainable option since it generates very minimal methane over long time periods. Compostable starch plastic bags have a large climate impact when put into landfills since they generate methane when they biodegrade, and should only be used when they end up at a compost facility.