05/05/2026
PDX-Earth Tip: Mouthwash is a common household product used for oral hygiene and nearly 200 million American make it a regular part of their daily routine. But your breath is minty fresh due to a mixture of chemicals and alcohol and that doesn’t even consider what happens to the residue you spit down the drain.
Mouthwash is increasingly under scrutiny for its harmful environmental impact. The cumulative effects of its production, packaging, and disposal can contribute to significant ecological issues, and many mouthwashes contain harmful chemicals and alcohol that can harm aquatic life when they enter waterways through wastewater systems.
Additionally, the plastic bottles and caps used for packaging often end up in landfills or oceans, exacerbating plastic pollution. The environmental concerns surrounding mouthwash highlight the need for consumers to consider eco-friendly alternatives and for manufacturers to adopt sustainable practices in production and packaging.
The extraction of fossil fuels for plastic production, the energy-intensive manufacturing process, and the lack of widespread recycling infrastructure for such small bottles all exacerbate its environmental footprint. A single 500ml mouthwash bottle requires approximately 100ml of crude oil to produce, a resource cost that multiplies with every purchase.
Mouthwash often contains chemicals that can damage aquatic ecosystems. Triclosan is an antibacterial agent commonly found in personal care products and studies have shown that even low concentrations of triclosan (as little as 0.05 parts per billion) can disrupt algae growth, a foundational element of aquatic food chains.
Chlorhexidine, often used in prescription mouthwashes for its potent antimicrobial properties, persists in water systems and can accumulate in sediments. Research indicates that prolonged exposure to chlorhexidine can harm aquatic invertebrates.
Alcohol, a common ingredient in mouthwashes, biodegrades more readily than triclosan or chlorhexidine, but its presence in water systems can disrupt microbial communities responsible for breaking down organic matter. This can lead to imbalances in nutrient cycling, potentially causing algal blooms or oxygen depletion in water bodies.
Certain mouthwashes also include microplastics as part of their formulation for texture, visual appeal and cosmetic purposes. These tiny microbeads do not break down easily and persist in the environment for decades, eventually degrading into even smaller nanoplastics. While the amount of microplastics in a single mouthwash use is small, repeated daily use contributes to cumulative exposure.
Research indicates that microplastics can accumulate in human tissues, including organs, breastmilk and urine.
Luckily, mouthwash can be made easily at home and eliminate the plastic waste and chemical exposure. Mixing 1 teaspoon of baking soda, 1 teaspoon of hydrogen peroxide, and 1 cup of water creates an effective and eco-friendly alternative.
Also, opting for alcohol-free mouthwashes or natural alternatives like oil “pulling” – the ancient Indian practice of swishing a natural oil like sunflower, coconut or sesame – around in your mouth can be a practical step.
For more, visit kpsu.org.
