Release of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) from cigarette butts into the aquatic environment: Levels and ecotoxicity.

Discarded cigarette waste may leach toxic elements and can contaminate different environments. In this study, the levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in cigarette butts (CBs) leachates were determined, and the release rate of these pollutants from three CBs types such as smoked CBs with and without tobacco (SCBs and SFs) and unsmoked filters (USFs) were examined. The mean concentration levels of PCBs compounds were <LOD-1.36, <LOD-1.02 and <LOD-0.86 μg/L in SCBs, SFs, and USFs leachates, respectively. The concentrations of OCPs in SCBs and SFs leachates were <LOD-0.14 and <LOD-0.10 μg/L, respectively. The toxic equivalent (TEQ) of the dioxin-like PCBs from the CBs leachate samples ranged from 2 × 10-6-1 × 10-4 ng/L. Notwithstanding the insignificant TEQ values in CBs leachates, continuous discharge and the toxicities of the PCBs in the aquatic environments could have harmfully impacts on the water boddies and/or human health. Globally, considering all the littered CBs and their chemical contents, further efforts are needed to investigate address, and mitigate this type of contamination.