Cigarettes are risky even after use


Cigarette butts are among the most common forms of litter in the world. Although a plethora of studies have clarified the impact of cigarette smoke on human health, the environmental impact of cigarette butts is still underestimated and poorly known. Cigarettes, and their remains, contain thousands of chemicals, such as nicotine. Among them, more than 50 are well-known human carcinogens. However, their toxic effects don’t end once smoked; in fact, if cigarette butts reach the waterways, their leachate can be acutely toxic to aquatic organisms, including microorganisms.

A research coordinated by Prof. Alessandra Negri (Università Politecnica delle Marche) and executed by Dr. Anna Sabbatini (Università Politecnica delle Marche) and colleagues, tested the acute effects of cigarette butts’ leachate on marine benthic organisms such as foraminifera.
Foraminifera are microbial eukaryotes widespread inhabitants of coastal sediments forming part of a key link in marine trophic chains. In particular, they react to change in abiotic and biotic factors and are often among the last eukaryotic organisms to disappear completely from polluted sites, making them exceptional bioindicators.
For this research, foraminiferal cultures of common coastal benthic species were used to investigate cellular stress after acute toxicity assay and potential effects on the biocalcification processes.

Rosalina globularis, one of the foraminifera used in the study

Naturally smoked cigarette butts were collected from the respective disposal units of the author’s department to make a leachate with artificial seawater where cultured benthic foraminifera were grown. Fourier Transform Infrared Imaging (FTIR) executed at the SISSI-Bio beamline at the Italian CERIC Partner Facility at Elettra Sincrotrone Trieste, allowed to better quantify, among others, the relative loss in calcium carbonate in the foraminifera.

The results of this study suggest the potential harmfulness of cigarette butts’ leachate that appears to have an acidifying effect on the solution, causing possibly damage to the marine bio calcifying organisms. Decalcification could depend on the pH reduction measured in the cigarette butts leachate and on the toxicity of other dissolved substances, in particular nicotine, which lead to physiological alterations and in many cases cellular death.

Further studies in this field are highly needed to better understand the adverse secondary effects of cigarette smoke affecting the environment.

Below the radio interview with Dr. Anna Sabbatini and Dr. Giovanni Birarda on their research work:


Cigarette butts, a threat for marine environments: Lessons from benthic foraminifera (Protista). Caridi F., Sabbatini A., Birarda G., Costanzi E., De Giudici G., Galeazzi R., Medas D., Mobili G., Ricciutelli M., Ruello M.L., Vaccari L., Negri A., Marine Environmental Research, 2020.