Impact of composting conditions on the nicotine degradation rate using nicotinophilic bacteria from tobacco waste

Abstract

In the past several decades, due to the increased population, the planet has faced immense problems with waste management. The need for recycling and upcycling is increasing. It has become imperative to extract maximum value from discarded products. There are nearly one billion smokers on the planet. Tobacco butts are toxic, and they pollute the environment. In this paper, the research objective was the bio-augmentation of waste in the context of composting tobacco and vegetable waste mixtures, and the determination of nicotine degradation rate depending on the composting conditions. Low-grade Virginia tobacco leaves that were discarded from further processing were used as base material. The experiment was conducted in triplicate. To each sample, bacteria from the species Brevibacillus were added, and then, samples were composted under diferent conditions (controlled, semi-controlled and non-controlled). Two more samples were formed as the control group, one without bacteria and one with only tobacco waste. The research was conducted over the period of one month with monitoring of the process parameters. The tobacco waste had a baseline nicotine level of 17,363 mg/kg. In all samples containing nicotine-degrading bacteria, the level of nicotine dropped below 10 mg/kg. There was a direct positive relationship between the rate of nicotine degradation, temperature and moisture content in the samples, as well as environmental temperature and relative humidity. The content of macro- and micronutrients makes the compost appropriate for organic fertilization in agricultural production.