Reduction of the environmental and health consequences of cigarette butt recycling by removal of toxic and carcinogenic compounds from its leachate.

Cigarette butt is a hazardous waste, and its management faces many challenges. The generation of leachate containing many pollutants including heavy metals is one of the limitations of recycling cigarette butts. The aim of this study was to reduce organic compounds and heavy metals in leachate resulting from cigarette butt recycling in an electrocoagulation reactor. For this purpose, two samples, including freshly smoked cigarette butts and littered cigarette butts, were processed and the treatment of leachate resulting from them was studied in an electrocoagulation reactor. The efficiency of leachate treatment was investigated in the treatment time of 10-40 min and current intensity of 20-100 mA. The results showed that the minimum reduction of chemical oxygen demand and turbidity was 25.3% and 33.4%, respectively. Increasing the current intensity and treatment time increased the efficiency of removing turbidity and chemical oxygen demand up to 47.1% and 41.2%, respectively, in optimum conditions. The reduction of nickel, chromium, cadmium, and lead in the lowest current density and minimum treatment time was more than 90%, which increased to more than 99% with the increase of the current density and treatment time. The use of electrocoagulation is a suitable solution to reduce heavy metals in leachate resulting from cigarette butt recycling, while the proper reduction of organic compounds in this type of leachate requires further treatment processes.

Quality variations of leachate resulting from cigarette filter recycling as a challenge for its management.

Recycling is known as a solution for cigarette filter management, but this may cause the release of trapped pollutants in it. Cigarette smoke toxins and chemicals that trapped in the cigarette filter can accumulate in the recycling leachate. In this study, littered cigarette filters and freshly smoked cigarette filters were recycled and the resulting leachate was analyzed. The results showed that the minimum and maximum Chemical Oxygen Demand (COD) of the studied leachates were 2100 mg/L and 11,300 mg/L, respectively. The maximum temporal variation in the studied leachate quality was 74.28%, but the maximum spatial variation was 314.2%. COD in the freshly smoked sample was 2600-9200 mg/L more than the littered samples. The average concentration of chromium, lead, nickel, and cadmium in littered samples was 0.023, 0.024, 0.045, and 0.019 mg/L, respectively. Environmental conditions such as humidity, the efficiency of the urban cleaning system in reducing the resistance of littered filters, the difference in the quality of the filter and tobacco, and the difference in smoking behaviors were effective in this variation. Reducing the toxicity of cigarette smoke and improving the efficiency of the urban cleaning system can lead to the same quality, but leachate treatment is necessary to reduce the environmental risk.

Clean environment index: A new approach for litter assessment.

Littered waste is one of the ubiquitous problems in urban environments. In this study, urban environmental pollution was evaluated for the first time using a new developed index. The findings indicated that cigarette butts with an average 58% are the largest share in the composition of littered waste. In addition, the numbers of littered wastes throughout the study area had a spatial variation. According to clean environment index (CEI), the entire study area was found to be in a moderate status. However, 40% of the study areas were classified in a dirty and extremely dirty status. Comparison of the studied urban land-uses showed that residential land use with CEI equal to 3.38 is interpreted in the clean status, while commercial land use with CEI equal to 15.05 can be classified in the dirty status. The application of CEI has a good capability to assess littered waste; this index can be employed to evaluate the pollution of urban sidewalks and other environments such as beaches.

Preparation of a cellulose acetate membrane using cigarette butt recycling and investigation of its efficiency in removing heavy metals from aqueous solution.

This study investigated the recycling of freshly-smoked cigarette butts (FCBs) and unsmoked cigarette filters (UCFs) into a cellulose acetate (CA) membrane. The both samples were prepared by means of a combination of seven cigarette brands, and the phase inversion method was used to recycle each sample into a membrane using N-methyl-2-pyrrolidone. The efficiency of the prepared membranes for the removal of chromium, cadmium, and lead from an aqueous solution in a forward osmosis reactor was investigated. The results showed that the both membranes had a smooth surface and macrovoids. The flux of the prepared membranes from the UCFs and FCBs recycling were 14.8 and 13.2 LMH, respectively. The porosity and reverse salt of the UCFs membrane were 61% and 3.5 gMH, while those for FCBs membrane were 58% and 3.9 gMH. The observed metal removal efficiency of the both membranes was in the range of 85 to 90%. However, increasing the concentration of metals up to five times caused a slight decrease in the removal efficiency (less than 5%).

The potential osteoporosis due to exposure to particulate matter in ambient air: Mechanisms and preventive methods.

Air pollution and health consequences associated with exposure to air pollutants, such as particulate matter, are of serious concerns in societies. Over the recent years, numerous studies have investigated the relation of many diseases with air pollutants. This review used a search strategy to provide the comprehensive information on the relationship between particle matters and osteoporosis. To this end, three search databases were used to find the articles focused on particle matters and osteoporosis. After the screening process, 13 articles related to the purpose of the study were selected and the relevant data were extracted. The results indicated that osteoporosis is significantly associated with PM10. However, this association with PM2.5 remains unclear. In addition, particle materials indirectly lead to the osteoporosis and bone fractures as a consequence of reduced UV-B, reduced adsorption of vitamin D. Furthermore, they can lead to other diseases by use of drugs with adverse effects on bone health, and creating conditions that may increase the risk of falling in the elderly. This review shows that although more accurate research is needed to determine the mechanism and risk of exposure to particulate matter in the air on bone health, the negative effects of this pollutant on bone mineral density (BMD) are evident.Implications: PM is usually classified by its size or aerodynamic diameter; PM10 denotes particles < 10 µm in diameter; PM2.5 particles are <2.5 µm in diameter. Many epidemiological studies have shown that short-term exposure to PM might reduce lung function. However, short-term effects might be reversible, and the main concern is attributed to long-term exposure. A major public health concern that may be affected by numerous metabolic and even environmental risk factors is osteoporosis. The purpose of this systematic review was to investigate the role of PM in the occurrence or exacerbation of osteoporosis in citizens.

Estimation of the heavy metals released from cigarette butts to beaches and urban environments.

Cigarette butts (CB) are considered as a commonly littered waste. This hazardous waste contains a variety of pollutants. This study was developed to estimate the release of some heavy metals from CBs to the environment in different climatic conditions in different scenarios. To this end, CBs samples were obtained through artificial smoking from 10 high-consumption brands in the Iranian market, and their samples in urban areas were taken and analyzed in terms of heavy metals pollution. The results showed that the average concentrations of Lead, Cadmium, Chromium, Zinc, Copper, Nickel in the studied CBs were 1.71, 0.36, 1.59, 24.61, 12.83, and 2.66 µg/g, respectively. The long persistency of CBs in the environment leads to increased release of all heavy metals to 9.7%. In addition, the rainfall can accelerate the leaching of heavy metals to 17.7% compared to the control scenario. The total mean concentrations of the studied metals in the CBs samples collected from the urban areas in rainy and non-rainy conditions were measured to be 32.67-51.81 µg/g, respectively. According to the data obtained for the amount of each heavy metal releases in four scenarios, 147.5 kg/year and 57.3 kg/year heavy metals are released to the environment in the worst and the best-case scenarios. This study showed that CBs littering lead to the release of heavy metals into the environment; it is necessary to reduce the density of CBs in urban and public environments by training the smokers as well as increasing the efficiency of the urban cleaning system.

Development a new index for littered waste assessment in different environments: A study on coastal and urban areas of northern Iran (Caspian Sea).

The coastal pollution has been evaluated using indexes like Clean Coast Index (CCI) in many countries. In this study, several coasts and urban areas in northern of Iran along the Caspian Sea, were assessed in terms of number and composition of litters. Furthermore, Clean Environment Index (CEI) was used for the first time to interpret the results. The results indicated that 60% of the coasts and 50% of the urban areas were in a dirty status and only 22% of the total surveyed areas were found to be in a clean status. The highest number of litters observed in the study areas was cigarette butt. Due to the impact of risk factor of different types of littered waste, it was obviously clear that CEI offers a more realistic and rigorous interpretation than CCI. Therefore, this new index can be considered to evaluate litters pollution in various areas.

Application of ultrasound irradiation in landfill leachate treatment.

Landfilling is known to be the most widely used method in municipal solid waste management in many countries. Landfill leachate containing different recalcitrant compounds are recognized to contaminate the soil and water and accordingly threat both the human health and environment. A variety of chemical and biological methods have recently been employed for landfill leachate treatment, one of which is the ultrasonic process. In this review, the efficiency of the ultrasound-assisted method for leachate treatment, factors influencing the treatment process are studied by defining a search protocol. The results showed that ultrasound can reduce pollutants by creating cavitation, microstreaming, and microturbulence. Increasing turbidity in initial of irradiation time and increasing the cost of treatment are the disadvantages of using ultrasonic in leachate treatment. Moreover, ultrasound-assisted method leads to improve the leachate quality, especially the COD/BOD. Therefore, ultrasound can be considered a good pretreatment for biological processes. Although, the application of this process in combination with other treatment processes such as biological processes and advanced oxidation increases the efficiency of leachate treatment, its efficiency depends on several factors such as exploitation features and leachate quality.

Effect of cigarette butt on concentration of heavy metals in landfill leachate: health and ecological risk assessment.

Cigarette butt is known as hazardous waste with numerous toxic and carcinogenic pollutants which impose serious concern for both the environment and human. Heavy metals are recognized as the most common pollutant in the cigarette butts. The concentration of some heavy metals (cadmium, chromium, nickel, lead and zinc) in leachate obtained from the pilot landfill with commingled waste and freshly smoked cigarettes butts were analyzed. The results showed that the addition of 0.76% (in weight) freshly smoked cigarette butts in landfilled waste increased total heavy metal concentration by 4.8%, while addition of 1.3% (in weight) freshly smoked cigarette butts leads to increased 3.72% of total heavy metals concentrations. An increased 10.52% and 3.43% health risk values were found from the leachate of the landfill pilot, where 1% freshly smoked cigarette butt and a littered cigarette were added, respectively. Overall, it can be concluded that cigarette butt landfilling is not recommended for management of this type of waste and is necessary to be replaced with less hazardous ways such as recycling.

Airborne particulate matter in Tehran's ambient air.

In recent decades, particulate matter (PM) concentrations in Tehran have exceeded the World Health Organization's (WHO) guideline on most days. In this study, a search protocol was defined by identifying the keywords, to carry out a systematic review of the concentrations and composition of PM in Tehran's ambient air. For this purpose, searches were done in Scopus, PubMed, and Web of Science in 2019. Among the founded articles (197 in Scopus, 61 in PubMed, and 153 in Web of Science). The results show that in Tehran, the annual average PM10 exceeded the WHO guidelines and for more than 50.0% of the days, the PM2.5 concentration was more than WHO 24-h guidance value. The PM concentration in Tehran has two seasonal peaks due to poorer dispersion and suspension from dry land, respectively. Tehran has two daily PM peaks due to traffic and changes in boundary-layer heights; one just after midnight and the other during morning rush hour. Indoor concentrations of PM10 and PM2.5 in Tehran were 10.6 and 21.8 times higher than the corresponding values in ambient air. Tehran represents a unique case of problems of controlling PM because of its geographical setting, emission sources, and land use. This review provided a comprehensive assessment for decision makers to assist them in making appropriate policy decisions to improve the air quality. Considering factors such as diversity of resources, temporal and spatial variations, and urban location is essential in developing control plans. Also future studies should focus more on PM reduction plans.

Challenges on the recycling of cigarette butts.

Cigarette butt (CB) is a crucial litter in urban communities because it may contain various toxicants. Due to serious limitations on incinerating or landfilling CB, recycling of this hazardous waste is essential. The objective of this study was to investigate the most important challenges in CB collection and recycling. To this end, a search was done on Scopus, PubMed, and Web of Science by defining a search protocol and identifying appropriate keywords. At the end of the screening process, 52 appropriate papers were selected. In this review, all methods for the CB recycling were considered. This review showed that nine categorizations of different products have been produced from the recycling of CBs, but three important challenges were identified for the recycling of this hazardous waste. It should be noted that finding solutions to these challenges may be helpful in better management of CB as a toxic litter.

Effect of COVID-19 pandemic on medical waste management: a case study.

Covid-19 Pandemic leads to medical services for the society all over the world. The Covid-19 pandemic influence the waste management and specially medical waste management. In this study, the effect of the Covid-19 outbreak on medical waste was evaluated via assessing the solid waste generation, composition, and management status in five hospitals in Iran. The results indicated that the epidemic Covid-19 leads to increased waste generation on average 102.2 % in both private and public hospitals. In addition, the ratio of infectious waste in the studied hospitals increased by an average of 9 % in medical waste composition and 121 % compared with before COVID-19 pandemic. Changes in plans and management measurement such as increasing the frequency of waste collection per week leads to lower the risk of infection transmission from medical waste in the studied hospitals. The results obtained from the present research clearly show the changes in medical waste generation and waste composition within pandemic Covid-19. In addition, established new ward, Covid-19 ward with high-infected waste led to new challenges which should be managed properly by change in routine activities.

Assessment of littered cigarette butt in urban environment, using of new cigarette butt pollution index (CBPI).

Cigarette butts (CBs) are hazardous wastes usually littered by smokers and are of the prevalence wastes in the environment. Although various studies have been done regarding the quantity of CBs on the coast, few studies have been conducted on its density and distribution in urban areas. Therefore, the objective of this study was to assess the quantity and distribution of CBs in urban areas to define an index to convert the results into comparable data in various conditions and cities. The data were obtained by visual surveys using field CB counts in the summer of 2019 in the city of Qazvin, Iran. Cigarette butt pollution index (CBPI) was defined by considering CB density, weather conditions, urban characteristics including the structure of the walkways, and distance from groundwater. The findings indicated that the average cigarette butts density in urban areas were found to be in range of 0.01 and 0.51. Spatial variation of CB was observed in the city due to urban characteristics like land use, differences in municipal services, and population density. The CBPI index calculated for a park showed the highest number whereas an administrative (official) area had the lowest CBPI of 0.15. Given the significant pollution of the city studied with CBs and the proper performance of CBPI in classifying various parts of the city, using this method and index can be a good way to assess CBs in the streets of most of the cities.

Municipal solid waste management during COVID-19 pandemic: a comparison between the current activities and guidelines.

The COVID-19 pandemic has affected everyone's lifestyle and this has resulted in a change in the quantity and composition of municipal solid wastes. Moreover, the post-pandemic waste management is very important as a bad management may lead to the more spread of the disease. The objective of this study was to evaluate the application of guidelines presented for the era of the COVID-19 pandemic in proper solid waste management. To this end, the data were collected by using interviews and field researches and then the obtained data were compared with the international guidelines presented by international organizations. By investigating the municipal waste management during this pandemic and its changes compared to pre-COVID-19, coordination of the plans with the guidelines was investigated. The activities of storage, collection, transportation, recycling, final landfill, as well as the observation of the health instructions by staff and informal sections were assessed in the current research. Although the results showed that the situation was satisfactory in the sections like health and safety of waste management operators due to the existence of protocols and general educations, the waste management plans have not been changed much from before the epidemic of the Coronavirus. The absence of a national policy and plan for waste management in the era of a pandemic and ignoring the guidelines developed by other countries and organizations were observable. Therefore, the codification of new policies for municipal waste management during an epidemic is necessary.

Study of littered wastes in different urban land-uses: An 6 environmental status assessment.

Littered waste is a severe environmental problem. Although there have been many studies on wastes littered in the environments like beaches and seas, there is insufficient information on littered wastes in the urban settings. In this research, employing visual survey by the field litter counts method, littered wastes in six urban land uses in Qazvin, Iran were studied. The results showed that administrative and recreational land uses, by an average of 5.22 and 9.59 items per 100 m, respectively, had the lowest pollution, while low-density commercial land use had the maximum pollution by 185.96 items per 100 m. Urban littered waste ratios were not the same in various land uses: cigarette waste and paper and cardboard accounted for higher than 80% of the whole littered wastes in most studied land uses. The cigarette butt was also the most frequently litter in the city. In terms of environmental status, administrative and recreational areas can be defined as places with good conditions, while low-density commercial land use had bad conditions. Consequently, urban land use was acknowledged as a significant factor in the density of littered waste. More attention to cleaning the commercial land use to reduce the density of littered waste, and also finding methods to decrease littering waste by citizens, is a need in urban environment.

Littered cigarette butt as a well-known hazardous waste: A comprehensive systematic review.

Most of cigarettes used in the world have filters. Following smoking, the cigarette butts (CBs) are often littered as wastes in the environment. CBs generally contain several toxic substances that are trapped in the cigarette filter. Filters are made of non-biodegradable materials and remain in the environment for a long time. Within this study, it is attempted to systematically review the articles on CBs and find out the answers to the problems associated with the factors including quantity, distribution, origin and toxicity of CBs in the environment. It is estimated that approximately 5.5 trillion cigarettes are being produced annually in the world and the CB wastes would reach 1.2 million tons and increase by 50% until 2025. CBs contain thousands of dangerous chemicals such as arsenic, benzene, hydrogen cyanide, PAHs, pyridine, heavy metals and so forth. It is also believed that eachCB can pollute 1000 liters of water. Given the inadequacy of mechanical equipment as well as the cost of collecting these wastes, there should be a special focus on these items as follows: producing cigarettes with degradable filters, reducing the rate of smoking in the world, reducing the toxic and chemical substances in the process of plant growth, processing and production of cigarettes, training people to discard CBs properly, putting legal and financial pressures on cigarettes production, and the last but not least, providing effective solutions for collecting CBs.

A systematic review on cigarette butt management as a hazardous waste and prevalent litter: control and recycling.

Annually, over 5.5 trillion cigarettes are produced worldwide, and it is estimated that 4.5 trillion cigarette butts (CBs) are still being littered in the world. The dispersal of the CBs has caused this hazardous waste to be considered as one of the most important litters and environmental risks all over the world. This systematic study with the search protocol definition and keyword identification was developed to find the CBs control and recycling methods by searching in five scientific databases. Founded articles were monitored and finally, 35 related articles were selected and studied by the authors. The results of this study showed that CBs recycling methods have been tested in 10 specific categories all over the world. The CBs have been applied without any pre-processing methods in the bricks and asphalt production. However, other applications of the CBs such as the absorbent material production, vector control, and use as a biofilm carrier in wastewater treatment need various processing methods. The researchers also presented models and suggestions such as taxes, penalties, and public education for the control of CBs littering. Despite the innovative methods applied for the CBs recycling in previous studies, CBs have not received much attention in terms of pollutant control and environmental issues in recycling processes.