The simple act of flossing is a universally recommended practice for maintaining oral health and preventing gum disease. Considering the billions of yards of floss discarded annually, its widespread use raises questions about its environmental footprint. It is worth examining if this necessary hygiene item contributes significantly to the global plastic waste crisis.
The Materials Causing Environmental Concern
Conventional dental floss is primarily manufactured from petroleum-based synthetic polymers, most commonly Nylon or Polytetrafluoroethylene (PTFE). Nylon floss is known for its strength and durability, while PTFE, often marketed as “glide” floss, is a single-filament plastic that resists shredding. Both materials are forms of plastic that are not biodegradable and can persist in the environment for hundreds of years.
The manufacturing of these synthetic flosses is a resource-intensive process that begins with crude oil, contributing to the product’s carbon footprint. Some PTFE flosses are also made using per- and polyfluoroalkyl substances (PFAS), a group of long-lasting chemicals. Beyond the floss itself, the small, hard-plastic dispensers are typically made from mixed plastics that are rarely accepted by municipal recycling programs. This packaging waste adds to the overall environmental burden.
Disposal and Microplastic Pollution
Once discarded, the non-biodegradable nature of conventional dental floss initiates a long process of environmental degradation. Unlike organic materials, these plastic strands do not decompose chemically; instead, they break down physically into smaller and smaller pieces. This physical fragmentation generates what are known as secondary microplastics, which are tiny plastic particles less than five millimeters in size.
The small, thin profile and tear-resistant design of floss mean it is easily carried into the environment, often bypassing traditional solid waste streams. When floss is improperly flushed, it enters the wastewater treatment system, but its minute size allows microplastics to pass through filtration processes. These particles then flow into rivers, lakes, and the ocean, becoming a pervasive form of pollution.
In aquatic environments, these microplastics are ingested by marine life, from zooplankton to larger fish and sea mammals. Accumulation in the digestive tracts of animals can lead to false feelings of fullness and starvation, disrupting the food web. Since humans are at the top of this chain, consuming seafood containing microplastics creates a pathway for these contaminants to enter the human body.
Environmentally Responsible Flossing Options
Consumers looking to reduce their environmental impact have several actionable options that maintain effective oral hygiene. Biodegradable floss made from natural materials provides a direct solution to the plastic waste problem. Silk floss, for example, is a protein fiber that is fully compostable and breaks down quickly at the end of its life.
Other plant-based alternatives include floss made from bamboo fiber or corn-starch-based polylactic acid (PLA). These options are coated with natural waxes, such as candelilla, instead of petroleum-derived coatings. Consumers should look for products packaged in refillable glass or stainless steel dispensers with compostable refill spools to minimize packaging waste.
For those considering reusable tools, water flossers use a pressurized stream of water to clean between teeth and are an alternative to single-use string. While they eliminate discarded string, these devices have their own environmental footprint due to the resources required for manufacturing the plastic housing, motors, and electronics. They also require electricity and water for daily operation. For maximum environmental benefit, a combination of sustainable string floss and a durable water flosser, used a few times a week for deeper cleaning, can balance oral health and ecological concerns.