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Objectives In this study, the absorption of heavy metals in the soil from smoking areas using indoor plants and electrical grounding was investigated to increase the utility of indoor plants for soil decontamination. Methods Soil from plant pots in a smoking area was collected for the experimental plant pot preparations. Some of the prepared pots were connected to electrical ground via an electrode. Kidney beans (Phaseolus vulgaris) were seeded, and their growth were observed. After 30 days of the cultivation, TOC (Total Organic Carbon), and metagenomics profiles in the soil was analyzed. To estimate the behavior of the heavy metals in soil and plants, Cadmium concentrations in the samples were analyzed using ICP-MS (Inductively Coupled Plasma-Mass Spectrometry). Results and Discussion The connection of the electrical ground to the plant pot induced the rapid growth of plant (48.2 ± 2.3% increase in stem growth), compare to the plant in the pot without the electrical ground. TOC analysis showed that the soil from the grounded pots showed the highest value, compared to the control soil (3.08 ± 1.22%), and the soil from the pot without ground connection (2.3 ± 0.1%). The ICP-MS analysis indicated that the plant body in the grounded pot had the highest cadmium concentration at 0.33 ± 0.018 μg/kg. Using the metagenomic analysis, biomineralization related bacterial species (Nocardioides sp., Streptomyces sp., Sphingomonas sp. etc.) were identified from the grounded soil sample. These results suggested that the indoor plant cultivation with the electrical ground connection as an electrical fertilizer enhances the cadmium absorption by plant, exudate secretion from the plant root, and bacterial flora change in the rhizosphere. Conclusion Cadmium in the soil from the smoking area was absorbed by indoor plant with the electrical ground. Therefore, the application of the electrical ground connection (earth) to the electrically insulated outdoor plant pots might enhance the plant growth rate and physiological activity. This application could be a novel soil decontamination method using plants.

Objectives The purpose of this study was to investigate the effect of plants on smoking area and its environment. For this purpose, two different smoking areas (with and without plants) were selected, and the number of smokers and spitting behaviors were monitored. Soil and leaves samples of each smoking area were taken to analyze the concentration of cadmium and distribution of soil microorganisms. Through this investigation, the role of plants in smoking area for the cadmium and microorganisms was estimated. Methods In the selected smoking areas, number of smokers and the number of spitting behaviors were monitored. Cadmium (Cd) concentrations of leaves, topsoil and rhizosphere obtained from the smoking areas were analyzed with inductively coupled plasma mass spectrometry (ICP-MS). The microorganisms in soil samples were analyzed using denaturing gradient gel electrophoresis (DGGE) and 16s rRNA amplicon sequencing based metagenomics. Results and Discussion In the case of smoking area with plants, number of smokers and number of total spitting behaviors were 176.67 ± 7.85 and 918.67 ± 40.8 times per hour, respectively. In smoking area without plants, the 153.67 ± 5.44 (smokers) and (829.8 ± 29.36 (spitting behavior) per hour were observed. Among the collected samples from the smoking areas, the highest Cd values (347.117 ± 24.542 μg/kg) were found in leaves of smoking area. In the case of smoking area without plants, the top soil samples showed the highest Cd concentration (295.77 ± 16.64 μg/kg). The results indicate that Cd released from cigarette ash, saliva and smoke can be accumulated in plants and soil. The results suggested that the presence of plants in the smoking area protect the accumulation of Cd in surrounding environments (soil and atmosphere). The metagenomic analysis of the soil samples showed that smoking and spitting behavior also affected microbial system in the smoking areas. The results showed that the microorganisms in smoking area were closely related to the heavy metal removing activities. Conclusion Results suggested that the cadmium distribution in the smoking areas was significantly affected by the presence of live plants. In addition, the presence of plants in the smoking area induced the difference species microorganisms. These results suggested that the presence of plants in smoking area can protect the spread of cadmium to the surrounding environment.

Objectives:The purpose of this study was to investigate the effect of spitting behavior on microbial public health in smoking areas. Through this investigation, bacterial concentration and spread of bacteria from the smoking areas were evaluated for the prospective public health and environment. Methods:The number of spitting and the spitting location in the smoking areas were measured visually by observers. For the microbial analysis, filter papers (5×5 cm) as sample collectors had been attached to the surface of the smoking areas for a given time. Using the collected filter paper, ATP bioluminescence measurement (RLU), colony forming unit (CFU) were measured. For the estimation of spitting behaviors in the smoking area on the spread microorganisms, saliva containing filters were selected from the areas, and fluorescent powder (0.01 g/cm2) was added to the papers. After 4 hours, the papers around the smoking areas were collected and the fluorescence activity was measured. Results and Discussion:The results showed that there was a clear relationship between the spitting behavior and the microbial activity in the smoking areas. In the case of sampling area A, the highest number of spitting was observed at the lunch hour (102 ± 16 times), and the RLU from the sample collected near the smoking area showed about 5,139 ± 1,267 RLU. When the RLU around the smoking area was measured, the lowest values were found at distance of 11 and 17 m from the cigarette bin (1,329 ± 148 and 1,204 ± 203 RLU), and it was confirmed that smoking and spitting did not occur at this sampling points. In the case of sampling area B, the highest number of spitting (45 ± 6 times) was observed at evening hour, and the RLU from the sample collected near the smoking area showed about 5,274 ± 1,297 RLU. The lowest value was in the sampling area B shown at 11 and 18 m (1,181 ± 243 RLU and 1,148 ± 168 RLU) from the cigarette bin, and it was also confirmed that smoking and spitting did not occur at this sampling points. The results indicate that the spitting during the smoking induced the increases of the microbial contamination of the public environment. The fluorescence powder diffusion analysis indicated that the saliva on the ground surface would enhance the spread of the microorganisms from the smoking area. Conclusions:Spitting in smoking areas can pose a high risk of microbial infection for smokers and non-smokers in smoking areas. Thus extensive and systematic attention related to the smoking manner must be paid to protect our public health.