In order of impact: lightweighting the bottle (-15 to -25% material directly reduces the footprint), switching to 50 to 100% post-consumer recycled PET, which divides the bottle’s carbon footprint by 2 to 3 if the supplier documents the actual content, adopting single-material packaging to prepare for PPWR compliance, and offering refills, effective only beyond 3 actual cycles. Switching to glass is rarely a good choice: a 50 ml glass perfume bottle emits 3 to 5 times more CO2e than an equivalent plastic bottle. Each option is quantified in a preliminary LCA before launching the moulds.
Read the source article: What is the environmental impact of cosmetics?