Many studies have been conducted on hospital solid waste management (HSWM) throughout the world, especially developing countries. This interdisciplinary study aims to summarize the available ...knowledge on the health and environmental risks of hospital solid waste (HSW) and also, develop a dynamic associational assessment among hospital solid waste generation rate (HSWGR), hospital solid waste composition (HSWC), gross domestic product (GDP) per capita, and environmental performance index (EPI) in some developing countries for the first time. The results of this study showed that researchers from India, China, Pakistan, Brazil, and Iran had found more evidence about the health, economic, and environmental issues in HSW than the other developing countries. The literature showed that the highest and lowest reported HSWGR (in national average level) belonged to Ethiopia (6.03) and India (0.24) kg bed −1 day−1, respectively. It has also been shown that all studied countries except Serbia, have higher levels of hazardous waste in their HSWC, based on the WHO's standard. Furthermore, the quantity and quality of HSW in developing countries depend on the service provided by the hospital, type of hospital, HSWM system, and the level of regional economic and culture. The association analysis showed that the EPI and GDP per capita of developing countries were significantly (p-value <0.05) associated with HSWGR, non-hazardous HSW, and hazardous HSW by the Spearman coefficients equal to 0.389, 0.118, −0.118, and 0.122, 0.216, and −0.346, respectively. However, it can be concluded that GDP per capita and EPI have a weak correlation with hazardous HSW and non-hazardous HSW. Moreover, HSW has many hazardous health and environmental risks such as dioxin and furan, that must be controlled and managed through implementing programs and policies based on sustainable development. As a final point, we believed that the present study can be considered to be a guide for future studies on HSWM in developing countries.
•Hospital waste is one of the most threating issue for health and the environment.•Developing countries are more vulnerable to hospital waste threats.•The main elements of hospital waste management in developing countries are reviewed.•The main threats of hospital waste management in developing countries are highlighted.
From a health prospective, it is critical to provide a comprehensive model which integrates all the parameters involved in virus transmission and its consequences on human body. In order to estimate ...the health risks, for workers and residents, associated with an exposure airborne viruses emitted from a wastewater treatment (WWTP), the concentration levels of viruses in emitted bioaerosols over a twelve-month period were measured by real-time polymerase chain reaction (RT-PCR). A combined Gaussian plum dispersion model and quantitative microbial risk assessment (QMRA) with Monte-Carlo simulation served as suitable explanatory tools to estimate the risk of acquiring gastrointestinal illness (GI) due to exposure to air containing Rotavirus (RoV) and Norovirus (NoV) bioaerosols. Additionally, DALY metric was applied to quantify the disability and mortality for workers and residents. RoV and NoV were detected above aeration tank with annual mean concentration 27 and 3099 (Viruses/m3.h), respectively. The medium calculated DALY indicator based on viral loads in contaminant source (RoV:5.76 × 10−2 and NoV:1.23 × 10−1) and estimated in different distances away (300–1000 m) (RoV:2.87 × 10−2- 2.75 × 10−2 and NoV:1.14 × 10−1-1.13 × 10−1) were markedly higher than the threshold values recommended by US EPA (10−4 DALY pppy) and WHO (10−6 DALY pppy). The sensitivity analysis highlighted dose exposure and disease burden per case (DBPC) as two most influential factors for both workers and residents following exposure to two pathogens of concern. Due to high resistance and high concentration in the environment, the presence of RoV and NoV can intensify the consequences of diarrhea especially for children under five years of age; A comprehensible and transparent presentation of DALYs and QMRA can help decision makers and responsibilities to justify the priorities of exposure to wastewater in comparison with other risks of daily life.
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•RoV and NoV were monitored with annual mean concentration 27 and 3099 (Viruses/m3h), respectively.•Pinf for RoV(8.3 × 10−3-2.3 × 10−3) and NoV(9.8 × 10−2-9.4 × 10−2) decreased at distances 300–1000 m.•The medium DALY for workers for exposure to RoV and NoV were 5.7 × 10−2 and1.2 × 10−1.
Capsule: Proposing a comprehensive model for measured RoV and NoV in WWTP air and their atmospheric dispersion to calculate corresponding QMRA and DALY for workers and residents.
The COVID-19 pandemic has an adverse effect on the environment. This epidemic’s effect on the waste composition and management and the impacts of municipal solid waste management (MSWM) on disease ...transmission or controlling are considered a compelling experience of living in the COVID-19 pandemic that can effectively control the process. This systematic review research was conducted to determine the effects of COVID-19 on the quantity of waste and MSWM. Searches were conducted in three databases (using keywords covid 19, coronaviruses, and waste), and among the published articles from 2019 to 2021, 56 ones were selected containing information on the quantity and waste management during the COVID-19 pandemic. The results showed that COVID-19 caused the quantity variation and composition change of MSW. COVID-19 also has significant effects on waste recycling, medical waste management, quantity, and littered waste composition. On the other hand, the COVID-19 pandemic has changed waste compounds’ management activities and waste generation sources. Recognizing these issues can help plan MSWM more efficiently and reduce virus transmission risk through waste.
Challenges on the recycling of cigarette butts Yousefi, Mahmood; Kermani, Majid; Farzadkia, Mahdi ...
Environmental science and pollution research international,
06/2021, Volume:
28, Issue:
24
Journal Article
Peer reviewed
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.
Abstract
Antibiotics are resistant compounds with low biological degradation that generally cannot be removed by conventional wastewater treatment processes. The use of yolk-shell nanostructures in ...spinning disc photocatalytic reactor (SDPR) enhances the removal efficiency due to their high surface-to-volume ratio and increased interaction between catalyst particles and reactants. The purpose of this study is to investigate the SDPR equipped to Fe
3
O
4
@void@CuO/ZnO yolk-shell thin film nanostructure (FCZ YS) in the presence of visible light illumination in the photocatalytic degradation of amoxicillin (AMX) from aqueous solutions. Stober, co-precipitation, and self-transformation methods were used for the synthesis of FCZ YS thin film nanostructure and the physical and chemical characteristics of the catalyst were analyzed by XRD, VSM,, EDX, FESEM, TEM, AFM, BET, contact angle (CA), and DRS. Then, the effect of different parameters including pH (3–11), initial concentration of AMX (10–50 mg/L), flow rate (10–25 mL/s) and rotational speed (100–400 rpm) at different times in the photocatalytic degradation of AMX were studied. The obtained results indicated that the highest degradation efficiency of 97.6% and constant reaction rate of AMX were obtained under LED visible light illumination and optimal conditions of pH = 5, initial AMX concentration of 30 mg/L, solution flow rate of 15 mL/s, rotational speed of 300 rpm and illumination time of 80 min. The durability and reusability of the nanostructure were tested, that after 5 runs had a suitable degradation rate. Considering the appropriate efficiency of amoxicillin degradation by FCZ YS nanostructure, the use of Fe
3
O
4
@void@CuO/ZnO thin film in SDPR is suggested in water and wastewater treatment processes.
Understanding the new insight on conversion of organic waste into value-added products can improve the environmental activities driven by microorganisms and return the nutrients to environment and ...earth. Here, we comprehensively review the available knowledge on application of garbage enzyme (GE) for different environmental activities including waste activated sludge, composting process, landfill leachate treatment, soil remediation and wastewater treatment with special focus on their efficiency. To identify peer-reviewed studies published in English-language journals, a comprehensive search was performed across multiple electronic databases including Scopus, Web of Science, Pubmed, and Embase. The search was conducted systematically using relevant keywords. The eligible studies were analyzed to extract data and information pertaining to components of GE, fermentation process operational parameters, type of hydrolytic enzymes and improved environmental performance. The findings derived from this current review demonstrated that GE produced from the fruit and vegetable peels, molasses or brown sugar (carbon source), and water within fermentation process contain different hydrolytic enzymes in order to facilitate the organic waste degradation. Therefore, GE can be considered as a promising and efficient pathway in order to improve the environmental activities depended on microorganism including, composting, wastewater and leachate treatment and bioremediation process.
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•A comprehensive review was performed on garbage enzyme application in environmental activities.•GE is a promising approach to convert the organic waste into value-added products.•Hydrolytic enzymes in GE facilitate the organic degradation and solubilization in environmental matrix.
Millions of tons of plastic are consumed annually in the world due to its significant characteristics such as durability, flexibility, and low weight. High consumption has made plastic one of the ...most important municipal solid waste compounds, the quantity of which has increased in recent decades. Plastic solid wastes are known as a threat to the environment, and its efficient management in various aspects such as cost–benefit requires decision-making tools. This study was assessing the cost–benefit of plastic solid waste management by development of an economic model, and definition of different scenarios to change plastic solid waste management status. The results showed that 8971 tons of plastic solid waste were generated annually in the studied city. The plastic solid wastes were finally transferred to either recycling or landfilling site through 5 identified routes. 83 percent of the total recycled plastic solid waste was due to post-separation routes, and only 7.7 percent of the total plastic solid waste was recycled from the source separation route. The economic comparison of scenarios showed that with the aggregation of post-separation routes, the net revenue of plastic solid waste management increases by 334,000 euro per year while increasing the public participation and the ratio of source separation route raises net revenue by 875,000 euro per year, which was the best economic condition among the scenarios. Using life cycle cost method and it’s respected developed economic model truly satisfied the conditions of both, the current plastic solid waste management and the alternative scenarios, and hence can be adopted as a tool for decision-making.
Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to ...remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe
O
@SiO
-NH
@CuO/ZnO core-shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV-Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O
played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.
Abstract
Environmental destruction, water crisis, and clean energy are among the very important challenges worldwide based on sustainable development goals. Photocatalytic fuel cell, a potential ...candidate for converting chemical energy into electrical energy through a pollution-free method, holds promise in addressing these challenges. In this regard, we investigated the response of a photoanode covered with UiO66-NH
2
-TiO
2
/NiF on a porous nickel foam as an attractive electrochemical response to remove antibiotics from aqueous solution and simultaneously produce electricity using a one-step hydrothermal synthesis. Nickel foam with its fine structure provides a suitable space for the interaction of light, catalyst, and efficient mass transfer of reactive molecules. It appears that it can be used as a competitive electrode in fuel cells. In order to investigate the properties of the photocatalyst, structural analyses including XRD, FESEM, FTIR, and UV–vis DRS were utilized. Additionally, polarization and electrochemical tests such as chronoamperometry and EIS were measured to further examine the electrochemical features of the PFC photoanode system. The obtained results under optimal conditions (SMZ concentration = 20 ppm, pH = 6, irradiation time = 120 min) were as follows: removal efficiency of 91.7%, P
max
= 16.98 μW/cm
2
, J
sc
= 96.75 μA/cm
2
, V
oc
= 644 mV. The light-induced current flow in UiO66-NH
2
-TiO
2
/NiF exhibited prominent and reproducible photocurrent responses, indicating efficient and stable charge separation in TiO
2
/NiF composite materials, which is a promising strategy for pollutant removal and simultaneous electricity generation.
Over the recent years, ever-increasing population growth and higher wastewater production has been a challenge for decentralized wastewater treatment plants (WWTPs). In addition, sludge treatment due ...to high cost for equipment and place make authorities to find a sustainable approach in both of economical and technical perspectives. One of the proposed solutions is transferring the sludge produced from decentralized WWTP to centralized WWTP. However, the appropriate proportional ratio of raw sludge to raw sewage is a challenge, otherwise, it make anaerobic conditions and sewage rotting along the sewer network based on permissible limit of dihydrogen sulfide (H
S) gas (5 ppm). In the present study, seven reactors with different ratios of sludge to raw sewage (0, 15, 20, 25, 50, 75, 100) were used to stimulate the feasibility of transferring Shahrake Gharb WWTP sludge along the wastewater transfer pipe to the centralized sewage treatment south Tehran WWTP plant in Tehran, Iran. The septic situation and H
S emission of different reactors within 7 h (Time to reach the compound in the south treatment plant) was analyzed by gas meter. The results indicated that the optimum ratio of sludge to raw sewage was 15% without H
S production during 7 h. In addition, due to the high volume of sludge produced by the Shahrake Gharb WWTP, the optimal ratio of lime to total solids (TS) in sludge (gr/gr) (0.6) increased the sludge loading rate from 15 to 30% without any H
S emission during the stimulation study period. Therefore, the lime stabilization and transfer of sludge from a decentralized WWTP to a centralized WWTP is a feasible way to manage the sludge and enhance the treatment capacity in local WWTP.