Assessing cigarette butt pollution on recreational beaches: A comparative study of two sampling methods and their impact on metal release

Discarded cigarette butts (CBs) are a significant source of environmental pollution. In areas with large amounts of cigarette waste, environmental hazards may arise due to the leaching of chemicals from filters and smoked tobacco. Accurately estimating the number of CBs on beaches requires a standardized method. Additionally, estimating the release of metals from these pollutants can provide important insights into beach pollution. This study compares two sampling methods to estimate CB waste on recreational beaches and evaluate the potential release of metals. In this combined experimental and meta-analysis study, circular methods with diameters of 5, 10, and 15 m were compared to a Flood Accumulation Zone (FAZ) method (1 m by 10 m, parallel to the waterline). Systematic study methods and meta-analysis were applied to estimate the release of metals along the Caspian Sea beaches. The Kruskal-Wallis test revealed significant differences in the averages of at least one sampling method (P < 0.006). Follow-up Mann-Whitney U tests showed no significant differences among the circular methods, but all circular methods significantly differed from the FAZ method (P < 0.05). The difference between the circular methods was smaller than the difference with the FAZ method. The minimum and maximum metal concentrations, in micrograms per square meter of Caspian Sea beaches, were associated with mercury and manganese. Circular methods with different diameters did not significantly differ and are effective in reducing CB accumulation due to coastal waves and wind. These methods can be considered standard for estimating CBs on beaches. Cigarette waste acts as a point source of metal pollution, with rapid leaching of metals increasing the risk of acute harm to coastal and marine organisms.