Smoked cigarette butts: Unignorable source for environmental microplastic fibers.

The pollution of microplastics and their potential environmental hazards have attracted considerable attention of the public. Cigarette butts, composed of cellulose acetate, are one of the most common plastic pollutants in the environment. Of all the litter that is discarded at will, cigarette butts are the most acceptable. Cigarette butts are dangerous pieces of plastic, but are usually not handled properly and consist of more than 15,000 detachable strands of plastic fiber. Discarded cigarette butts may be carried into rivers and lakes, and finally into the ocean. The plastic fibers will continuously release microplastic fibers into the environment. About 300,000 tons of potential microplastic fibers may enter the aquatic environment from this source per annum. Additionally, toxic substances, such as nicotine, carcinogenic tar, and polycyclic aromatic hydrocarbons, have strong toxic effect, which will cause serious damage to aquatic organisms. However, the mechanism and rate of microplastic fibers release from smoked cigarette butts and the joint toxicity of microplastic fibers and toxic pollutants to aquatic organisms are still in the initial stage. Therefore, it is necessary to understand the mechanism of cigarette butts releasing microplastic fibers, the potential impact on the environment and possible measures to reduce the impacts of cigarette butt litter. The aim of this paper is to evaluate the potential sources of smoked cigarette butts as environmental fiber microplastics and the potential ecological effects of the released microplastic fibers on the ecosystem. In addition, some ways which could help to tackle problem of smoked cigarette butts pollution have also been proposed.