Cigarette butts as a microfiber source with a microplastic level of concern

Area of Science:

• Environmental Science
• Polymer Science
• Ecotoxicology

Background:

• Microplastic pollution is a significant environmental concern, with microfibers (MFs) being a prevalent type.
• Cigarette butts, commonly found in clean-ups, are a major source of hazardous debris and can release MFs.

Purpose of the Study:

• To quantify the detachment rate of MFs from cigarette butts (SFs).
• To assess the acute aquatic toxicity of SF-derived MFs.
• To evaluate the degradability (aquatic, thermooxidative, photo) of SF-derived MFs.

Main Methods:

• Quantification of MF detachment from SFs.
• Acute aquatic toxicity testing using Daphnia magna.
• Degradability assessment via ATR-FTIR analysis and gravimetry.

Main Results:

• SFs detach approximately 100 MFs (<0.2 mm) per day, potentially contributing 0.3 million tons annually to aquatic environments.
• Significant acute aquatic toxicity was observed, with Daphnia magna EC100 and EC50 values of 0.620 SF/L and 0.017 SF/L, respectively.
• SF-derived MFs demonstrated low degradability under aquatic, thermooxidative, and photo-degradation conditions.

Conclusions:

• Microfibers from cigarette butts represent a substantial, under-addressed source of microplastic pollution.
• The low degradability and toxicity of these MFs raise concerns for aquatic ecosystems.
• Effective management of cigarette butt waste is crucial to mitigate microplastic contamination.