Toxicity of cigarette butts and possible recycling solutions-a literature review.

Tobacco is a worldwide-consumed product, which in addition to causing public health-related issues is responsible for the most common form of litter in the world-smoked cigarette butts (CBs). A large attention has been drawn to this question, since this specific waste type tends to end up in terrestrial and aquatic ecosystems, posing serious threat to a range of life forms. Decomposition may take several years to occur because cellulose acetate is hardly accessible, before deacetylation, by bacteria and fungi. This review concerns the toxicity derived from smoked cigarette butts, as well as innovative ecological solutions for solving the CB litter problem. Toxicity studies have demonstrated the critical influence of chemicals present in smoked CBs to the environment as a whole, but also the physical contaminating potential considering micro- and nanoparticles derived from CB material. Nevertheless, several technological approaches were aimed at unveiling hidden value within used CBs, as well as propositions for incorporation of this residue in large volume production items or direct recycling. In summary, several methods are available to alleviate CB pollution, while appropriate and efficient collection logistics by consumers appears as the main bottleneck for an effective recycling. It is also clear that while considerable progress has been made recently in light of CB recycling solutions, there is still a vast research capacity in this regard.