For several years, Russian scientists have been monitoring the decomposition of cigarette butts in different climatic zones, and have found that earthworms and microorganisms play a much larger role in this process than previously thought.
According to the journal Regions.ru, researchers from the Institute of Ecology and Evolution of the Russian Academy of Sciences have found that earthworms and other microorganisms can accelerate the decomposition of cigarette filters in nature. Their findings indicate that the presence of earthworms speeds up the loss of mass from cigarette butts by consuming the paper lining of the filter.
The study involved burying samples of regular cigarette filters and those with carbon filling in the soil, monitoring changes in their mass over three years. The results showed that the rate of decomposition of cigarette butts is directly dependent on climatic conditions. In cold regions, such as the tundra and northern taiga, decomposition was slow, with the mass loss of the filters not exceeding 20% throughout the study period. However, in warmer and wetter regions, such as the southern taiga and broadleaf forests, the loss reached approximately 70% during the same period.
The researchers also discovered that microscopic fungi play a key role in the decomposition process. At a deep lake near Moscow, they identified more than 30 different types of microscopic fungi on cigarette butts just two months after the experiment began. Earthworms also contributed to the process, reducing the mass of cigarette butts by about 15% by consuming the papery part of the filter, which constitutes roughly a quarter of its mass. Without these worms, this decomposition phase would have taken between one and two years.
The researchers emphasize that the study's findings do not mean that cigarette butts are now environmentally safe, as the primary plastic material in the filters, cellulose acetate, may remain in the environment for many years, especially in cold and dry regions.
The researchers noted that the study is still ongoing, and they hope to reach definitive conclusions regarding the time required for the complete decomposition of cigarette filters after the end of the multi-year experiment.
