The Graduate School of Public Health (SDSU) has received a grant for a three year study of the environmental impact of tobacco product waste. Funded by California Tobacco- Related Disease and Research Program (TRDRP), it is the first large-scale project to investigate the environmental impact of tobacco product waste.
The study, “Assessing Toxicity of Tobacco Product Waste to Humans,” is being led by Principal Investigator Dr. Eunha Hoh, associate professor, and Dr. Rick Gersberg, a professor and the interim director of the Graduate School of Public Health, who were awarded the research project award of over half a million dollars for three years, beginning December, 2014.
The study focuses on discarded cigarettes butts. Discarded cigarette butts are the most prevalent litter found in ocean and inland water ways. However, their contribution to environmental damage has not been evaluated. Cigarette filters are made of non-biodegradable plastic. The filters trap particulates and less volatile chemicals in main stream cigarette smoke.Therefore, it is reasonable to expect that cigarette butts contain harmful chemicals due to the trapped chemicals in filters and chemicals in unburned tobacco. An essential question is whether harmful chemicals found in discarded butts leach into environments, such as surface waters, soil, and sand. If so, what are the short- and long-term fates of these chemicals? Are they toxic, and if so, in what ways? Moreover, the recalcitrant nature of cigarette filters make them a long-lasting carrier of harmful chemicals in their journey beginning as discarded trash and ending as a source of waterborne contamination.
Drs. Hoh and Gersberg propose to identify leachable chemicals and estimate the fate and possible bioaccumulation and toxicity of these of the leachable chemicals. Toxicity of cigarette butt leachate will be tested by in-vitro bioassays which can provide biological mode of actions at very low concentrations, through collaboration with Daniel Schlenk, professor at University of California Riverside. It is also important to determine whether chemicals can enter food chains, especially in aquatic environments. If so, this will provide a major pathway of human exposure. This will be tested by doing EPA-standard bioaccumulation testing in freshwater fish and saltwater fish.
Ultimately, they hope to identify and rank those constituents that may be harmful to humans. Co-investigator Dr. Thomas Novotny who has been working on the environmental impacts of tobacco use, considers that the study results will be critically important to determine the identity of cigarette butts as a hazardous waste.