Investigation on Toxicity of Leachate of Cigarette Butts Collected from Addis Ababa on Swiss Albino Mice

Abstract

Background: Cigarette butts are the most common form of litter in the world. They are toxic to microorganisms, fish and other marine organisms and birds, but no studies have been done on their toxicity to mammals. The aim of the study was to test the toxicity of cigarette butt leachate on mice. Methods: A total of 10,20,30,40 and 75 cigarette buttes with remaining tobacco at the end and/or without were used to prepare leachates. Two Swiss albino mice (adult and baby) groups were allowed to drink the prepared leachates by soaking in water with different number of buttes’ according to study protocol used for adult and baby mice. The weights of the mice, as well as the amount of food and fluid consumed were followed and compared over time. Necropsies were performed and tissues were weighed and evaluated by histological staining with eosin and hematoxylin. Blood glucose and liver function tests (Alanine Aminotransferase, Aspartate Aminotransferase and Alkaline Phosphatase) were also measured. Data was collected from the respective experiments, and analyzed using SPSS version 21 software. Results: The mean water only intake of the mice was 35; the mean fluid intake of 10 butt leachate with tobacco was 18; the mean fluid intake of 30 butt leachate with tobacco was 12 and the mean fluid intake of 75 butt leachate with tobacco was 10ml. All fluid intake values were reported in mL/5mice/day. The body weight of experimental mice has shown statistically significant difference in those arms, taking 75 cigarette butt leachate with associated tobacco (pvalue, 0.00078).  The lung tissue of the mice that drank leachates made with tobacco-associated butts showed increased air space volumes and alveolar fibrosis.  Conclusion: Cigarette butts resulted in reduced weight gain during growth, reduced mass and size of tissues and organs, and pulmonary emphysematous changes in mice. Since there are few studies on effect of cigarette butt on mice, more studies should be done in this area.  

Keywords: Cigarette Butt, Leachate, Nicotine, Lung Toxicity