To effectively use plastic bags for odor-proofing, seal smelly items in airtight bags and store them in a cool, dry place. For persistent odors, add an absorbent layer like baking soda or activated charcoal between the item and the bag. Regularly check and replace the absorbent material if it loses effectiveness. Freezing items in sealed plastic bags can also neutralize odors by slowing bacterial growth.

The primary mechanism involves creating an airtight environment to prevent odor molecules from escaping. Plastic bags, especially thick or heavy-duty varieties, form a barrier that traps volatile organic compounds (VOCs) responsible for odors. Activated charcoal, known for its adsorption properties, can reduce odor intensity by up to 80% within 24 hours, as shown in a 2019 study published in the Journal of Environmental Chemical Engineering. Freezing, on average, reduces odor compounds by 70% within 48 hours, per research from the International Journal of Food Microbiology. Additionally, a 2021 analysis by the USDA found that sealed plastic bags containing baking soda decreased meat odor by 65% over seven days compared to unpackaged counterparts. These methods work because plastic bags minimize air exchange, while absorbents chemically bind odor particles. However, prolonged use without refreshing absorbents may lead to residual odors, as VOCs can re-emerge if the barrier is compromised. Always ensure bags are clean and intact to maintain efficacy.