Optimization of Buffer Conditions for Nicotine Detection in Soil by Using HPLC/UV During Campus Tobacco-Free Promotion

Nicotine from discarded cigarette butts can leach into the soil with the aid of rainwater. Nicotine will not degrade easily and becomes a harmful mixture in the environment, where non-smokers are dangerously exposed to those hazards. This is called “third-hand smoke” (THS). As public properties, such as Emporia State University (ESU), begin implementing tobacco-free polices, it is expected that analyzing soil samples for nicotine will help determine the nicotine exposure in such a public environment.The data was collected in the spring and summer semesters of 2018 during the period in which the tobacco-free policy was implemented on campus. To extract nicotine, soil samples were mixed with mobile phase solution and centrifuged. High performance liquid chromatography (HPLC) was used to separate the molecules within the supernates, and those molecules were analyzed with ultraviolet (UV) detection. The retention time of nicotine peak was substantially shortened by half from 7 minutes to 3 minutes. The limit of detection of 46 ppb for nicotine was achieved by using HPLC/UV.The findings of this research showed that in the spring of 2018 when the tobacco-free policy was enforced on the ESU campus, there was a significant decrease in the nicotine concentration in ESU soil. Further, the methods that were developed in the project can be adapted to similar types of research, such as determination of nicotine or cotinine contaminations in soil samples, which could enhance the knowledge of the soil and water qualities.