Why the same bag has two different thresholds
Whether the plastic bag gets a second life as a bin liner nearly doubles the reuse count a tote must reach.
A disposable plastic bag used once and thrown away carries a small but real impact. Used again as a bin liner, it delivers two services from one bag, so the tote has to work harder to stay ahead: 131 becomes 327 for cotton, 11 becomes 26 for recycled polypropylene.
This is the single largest lever a shopper controls. Keeping the plastic bag as a liner raises the bar for every reusable alternative; discarding it immediately lowers the bar.
- Plastic bag discarded after one use: lower reuse threshold for the tote
- Plastic bag reused as a bin liner: threshold rises by roughly 2.5 times for cotton and 2.4 times for polypropylene
- Thresholds are life-cycle figures: they count production, transport and disposal, not just the bag in hand