Solid Waste Samples Research Articles

Conventional and fourier transform infrared characterization of waste and leachate during municipal solid waste stabilization

Solid waste and leachate samples from bench-scale anaerobic bioreactors and flushing bioreactors (FBs), containing mature waste were characterized using Fourier Transform Infrared Spectroscopy (FTIR) to provide a better understanding of the changes in waste characteristics when waste transitions from mature to stabilized. Humic acid (HA) extracted from mature waste and waste removed from the FBs were characterized using FTIR and 13C nuclear magnetic resonance. FBs were operated under three different treatment scenarios (flushing with clean water, recirculation of leachate treated by chemical oxidation, and recirculation of leachate treated by chemical oxidation with waste aeration. FTIR spectra of FB waste and leachate supported the stabilization of waste that occurred after the additional treatment. There was a shift in the dominance of organic to inorganic functional groups when compared to changes in conventional parameters that aligned with published values on waste stability. HA extracted from the mature waste were dominated by aliphatic carbon and aromatic carbon was less intense. Treatment by flushing resulted in a decrease in aliphatic carbon and an increase in aromatic carbon. HA extracted from reactors with oxidized leachate recirculation and aeration decreased in aliphatic carbon content, with minimal change in aromatic carbon. Therefore, the additional treatment did not result in an increase in the reactivity potential of the HA which aligns with FTIR and principal component analysis. Results suggest that spectroscopic techniques could be used to assess the stability of waste samples as opposed to more time-consuming analyses.

Contribution of Each Combustible Waste to the Element Content of MSW Incineration Residue

To investigate the origin of toxic/beneficial metals in incineration residues, we tried to estimate the contribution of each combustible waste to various elements in incineration residue. Municipal solid waste (MSW) sample to be incinerated was collected from a waste pit of incineration plant A by a crane and compressed according to the quarter method. After excluding metals and incombustibles, the MSW sample was divided along with the material such as kitchen waste, vinyl and plastic, wood, rubber, and so on. Each sample was dried at 105°C for 2 hours to obtain the water content, and cut into small piece. Each sample was placed in a magnetic crucible and closed with a lid, then, heated at 650°C in a muffle furnace to obtain constant weight after ignition loss. After the heat-up and cool down, two-stage extraction consisting of aqua regia decomposition and alkali fusion was carried out on each ash. Each extract was subject to ICP-OES and ICP-MS to determine the element content in each combustible. Element composition of the ash was well correlated with the element composition of actual incineration residues collected at the same incineration plant on the same day of sampling. As a source of toxic metals, 68% of Pb was proved to originate from vinyl and plastic. As for Cd, woods accounted for 38% and rubber and leather accounted for 29%, respectively.

A comparison of methods for early prediction of anaerobic biogas potential on biologically treated municipal solid waste

Anaerobic gas production tests, generically Biochemical Methane Potential (BMP) or Biogas Potential (BP) tests, are often used to assess biodegradability, though long duration limits their utility. This research investigated whether simple modelling approaches could provide a reliable earlier prediction of total biogas production. Data were assessed from a non-automated biogas test on a large number of both fresh and processed municipal solid waste (MSW) samples, sourced from a mechanical biological treatment (MBT) plant. Non-linear models of biogas production curves were useful in identifying a suitable test endpoint, supporting a test duration of 50 days. Biogas production at 50 days (B50) was predicted using the first 14 days of test data, using (a) linear correlation, (b) a new linearisation process, and (c) non-linear kinetic models. Prediction errors were quantified as relative root mean squared error of prediction (rRMSEP), and bias. Predictions from most models were improved by removing the initial exponential increase phase. Linear correlation gave the most precise and accurate predictions at 14 days (rRMSEP = 2.8%, bias under 0.05%) and allowed acceptable prediction (rRMSEP <10%) both at 8 days, and at 6 days using separate correlations for each sample type. Of the other predictions, the new linearisation process gave the lowest rRMSEP (10.6%) at 14 days. More complex non-linear models conferred no advantage in prediction of B50. These results demonstrate that early prediction of anaerobic gas production is possible for a well-optimised test, using only basic equipment and without recourse to external data sources or complex mathematical modelling.

Physical, chemical and geotechnical characterization of fly ash, bottom ash and municipal solid waste from Telangana State in India

Utilization of fly ash, bottom ash and municipal solid waste in the field of geotechnical engineering necessitates determination of its physical, chemical, morphological and engineering properties. This paper presents detailed physical, chemical and geotechnical characterization of fly ash, bottom ash and municipal solid waste from Telangana State in India. Fly ash and bottom ash samples were collected from Kakatiya thermal power station in India. Municipal solid waste (MSW) sample was collected from Borabanda municipal dump site in the city of Hyderabad, India. From the experimental results, it is noticed that specific gravity of fly ash, bottom ash and municipal solid waste were found to be 1.86, 1.77 and 2.2 respectively. Presence of quartz and mullite; quartz, mullite and calcium carbonate; and quartz and corundum are found to be predominant in fly ash, bottom ash and MSW respectively. The peak friction angle of fly ash, bottom ash and municipal solid waste were found to be 37.02°, 33.77° and 35.23° respectively. Permeability characteristics of fly ash, bottom ash and municipal solid waste were observed to be 1.01E−04 cm/s, 2.01E−04 cm/s and 1.16E−04 cm/s respectively. From the observation of experimental results, it can be concluded that fly ash, bottom ash and municipal solid waste from Telangana state are effective material to be used as backfill material, filter material and embankment construction.

Gross Calorific Value of Combustible Solid Waste in a Mass Burn Incineration Plant, Benin City, Nigeria

Some solid waste incinerators burn waste that does not possess enough calorific value that justifies the installation of an energy recovery facility, this implies that a substantial amount of energy would be provided by an auxiliary burner. Hence, the presentation of this paper was to evaluate the feasibility of setting up a mass burn incinerator with energy recovery facility using the gross calorific value (GCV) of waste generated in Benin City of Nigeria which is considered as case study. Solid waste samples (wood, leather rubber, plastic, paper, textile material etc.) were collected from Benin metropolis and their GCV were determined in a laboratory using an XRY-1A digital oxygen bomb calorimeter. The average calorific value of the waste samples calculated from the experiment was 20,198.89kJ/kg, this value is higher than the 7,000kJ/kg minimum average calorific value of solid waste required for setting up an incineration plant with energy recovery.Keywords: Incineration, Solid waste, Gross calorific value, Energy recovery

Physico-Chemical Properties In Degradation Of Oil Palm Solid Waste By Microbial Inoculant And Palm Oil Mill Effluent

Composting fiber ex-fibercyclone and oil palm midrib are the alternative method in waste management and the yielded organic residues that have potential to enhance soil and to assists plant growth. The aim of this study was to evaluate the physico-chemical properties of oil palm midrib and fiber composted by palm oil mill effluent (POME) and microbial inoculant provided commercially. This study was arranged in randomized block design (RBD) and the design was divided into 2 groups based on the type of solid waste samples used. Within each group the solid waste (SW) was tested as follows: P1 = SW was inoculated by activator A (Control); P2 = SW was mixed with cow manure and inoculated by activator B; P3 = SW was mixed with cow manure and inoculated by POME; P4 = SW inoculated by activator B; and P5 = SW inoculated by POME. Physico-chemical status were periodically tested along the experiment. The results of this research showed that composting process had formed mesophilic temperature with the highest at 39.25°C; with a range of pH 6.02 – 8.29 and conductivity 0.35 – 1.84 mS/cm at week 16. The C/N ratio of compost product at the end of composting was 7.05 – 12.41. Results revealed that the final of compost C:N ratio <20 and the macronutrient content fulfilled the requirement of Indonesian Standard Quality of Compost which potentially used as an alternative growing media for plant.

A Study on Solid Waste Composition in Kanchanpur District, Nepal

Background: Solid waste is a by-product of human activities. It has become an alarming challenge during recent decades in many cities of Nepal. Quantity and characteristics of solid waste have changed as a result of the modification in people’s lifestyle. The purpose of this study is to characterize the composition of solid waste in Bhimdatta Municipality of Kanchanpur district, Nepal.Methods: In between July to September 2015, a total of 45 households, 15 commercial places, 15 institutions were selected randomly. Solid waste samples were collected in recommended plastic bags. The collected wastes were categorized and weighted. Direct observation of municipal solid waste collection and its disposal practices were also performed. Qualitative information was collected from focus group discussion.Results: A total of 446.7 kg of solid waste was collected and the highest proportion (66.4%) was organic in composition. In the daily production of overall solid wastes, households were ranked the first (23.3%) and followed to the hotels and lodges (20.4%). The commercial centers produced the highest amount of all types of wastes. The crude waste dumping practice in the open and vacant areas was found a threat to human health, causing ecological imbalances and also bringing land, water, and air pollution.Conclusions: The rapidly growing population in the urban region of the study area has become an urgent issue in the production of several types of solid wastes. The organic waste was generated in the highest amount and maximum proportions of solid waste were produced from commercial centers.

KARAKTERISTIK PADATAN ANAEROBIK HASIL PENGELOLAAN TERINTEGRASI SAMPAH KOTA SEBAGAI PUPUK ORGANIK

The issue of municipal waste is a serious problem that threatens environmental sustainability. One of the efforts to overcome this problem is integrated city waste management in the bioreactor. Integrated management leaves a problem, namely the presence of waste in the form of anaerobic solids. The study aimed to analyze the waste content of anaerobic solids in municipal waste in bioreactors and the potential use as organic fertilizer. The method used in the study was analyzing anaerobic solid waste samples from 5 bioreactors containing various sizes of municipal wastes. Sampling by opening the control hole in the middle part of the bioreactor were A: slury, B: 1-3 cm, C: 4-6 cm, D: 7-9 cm, E: without treatment. The sampleswere packed using plastics, then analyzed in laboratory. Observations included analysis of the density of anaerobic solids during the 150-day conversion process in the laboratory. Parameters analyzed included pH, C/N ratio, total solid (TS), volatilesolid (VS), moisture content, nitrite (NO2-N), temperature, and ash content. The results showed that the conversion of anaerobic solids in all sizes of municipal waste in bioreactors showed differences and decreased values indicated by C/N ratio, total solid, volatile solid, nitrite (NO2-N), and moisture content, while ash content increasedand temperature of the material fluctuate during the bio-conversion process. All parameters met the standards and were safe to return to the environment as an organic fertilizer. Keywords: anaerobic solids, municipal waste, oganic fertilizer, bioreactor, bio-conversion

Development of an eco-friendly method for the determination of total polychlorinated biphenyls in solid waste by gas chromatography-mass spectrometry

A simple and efficient solvent-free method for the quantification of total polychlorinated biphenyls (PCBs) in solid waste matrices by gas chromatography-mass spectrometry is proposed. Solid waste matrices spiked with Aroclor 1242 and Aroclor 1254 were used in this study. In this new approach, the cavity of the rotating disk device is loaded with the solid waste sample and water is used as leaching solvent allowing desorption of the analytes. Concomitantly a solid phase microextraction fiber is directly immersed in the water to extract the analytes. In order to improve the extraction efficiency, parameters such as pre-equilibrium, extraction time, temperature, ionic strength and the presence of an organic solvent were optimized. The values obtained for limits of detection (LOD) and limits of quantification (LOQ) are suitable for the determination of total PCBs in solid wastes and, subsequently, the most appropriate destination for the disposal of the waste can be selected. The accuracy and precision of the method exhibited satisfactory results, providing relative recoveries of 80.2–96.0% for total PCBs (at three spiked levels) and the relative standard deviations were between 2.5% and 15.5%. These results showed that the proposed method is a promising alternative for the determination of PCBs in solid wastes.

Electricity Generation Potential of Municipal Solid Waste of Nepal and GHG Mitigations

This research is carried out to assess the current status of municipal solid waste of municipalities of Nepal and its potential for energy recovery. During the year 2016, solid waste samples were collected by door-to-door collection method and the total energy content of the municipal waste was calculated using Bomb Calorimeter in the laboratory. During the study period, the total waste generated at Kathmandu metropolitan city was 566 tons per day with 0.3 kg per capita contribution. The major waste constituent was the organic with 67.77% of the total waste volume. Other bulk wastes were plastic and paper constituting 10% and 5% by volume respectively. Rest of the wastes (8%) was categorized as “other". In average, the total moisture content in the wastes was 49.93%. Total waste generation of all municipalities was found 1435 tons per day. The calorific value of the plastic wastes had highest energy content (40.61 MJ/kg). The organic (15.68 MJ/kg) and paper (15.61MJ/kg) wastes had similar energy content while the other wastes had slightly higher energy content (17.57MJ/kg). The net energy available and, thus, lost after dumping of the solid waste was 71,895,056 MJ which is equivalent to 4262 MWh which can run 52 MW plasma arc gasification power plant. The waste to energy potential of Kathmandu Metropolitan city was found to be 19 MW. Total reduction in GHG emission was found 220,690 kg CO2 eq kg per day.Journal of the Institute of Engineering, 2018, 14(1): 151-161

Utilization of Municipal Solid Waste Ash in Concrete by partial Replacement of Cement

The problem of solid waste is being emerged increasingly due to the increased quantity of solid waste as a result of population’s increase .From the point of view of environmental and energy concerns, it is preferable to reuse the organic and inorganic components of solid waste in order to minimize the cost. In this investigation, the possibility of using solid waste ash (SWA) as a partial replacement of cement and its effect on the mechanical properties of concrete was studied. Samples of municipal solid wastes were collected were burring and changed to ash. A total of 50 cubes, 15 small cubes, and 30 cylinders, as well as 5 prisms were prepared .Various properties of solid waste ash are added to the cement mistures with percent's of 5, 10, 15 and 20 percent by weight of solid waste ash. A concrete mix with a percent solid waste ash was used as reference. Pozzolanic activities of all mortars, and setting times of all pastes, and workability of all mixes were investigated .Compressive strength, splitting tensile strength, absorption, and drying shrinkage for reference for reference and solid waste concrete specimens were investigated at various ages. Results demonstrate that the pozzolanic activity was within ASTM requirements for the cases of 5% and 10% ash replacement. For 15 and 20 percent replacement this activity was only slightly less than the ASTM value. The 90-day compressive strength rose, in comparison with control specimens, with 5 percent replacement and was only slightly lower at 10 percent replacement. In splitting tensile strength was at least equal to reference specimens for all replacement ratios. The rise in these values, over the reference specimens, ranged between 0 to 21 percent for the case of 20 and 5 percent replacement, respectively.

Evaluation of combustibility and energy potential of municipal solid waste: The case of Esenler Municipality

Waste management legislation has been amended and a policy has been set up to reduce the amount of waste sent to landfills within the framework of the EU regulations adoptions in Turkey. In this respect, the disposal of biodegradable wastes on landfills have been introduced and restricted with The Regulation on Landfilling of Wastes. For this purpose, the use of mechanical, biological and thermal processes to reduce waste amounts is envisaged. In this study, solid wastes produced in Esenler Municipality is characterized. Representative municipal solid waste (MSW) samples were collected and calorific values of MSW obtained from different socio-economic regions within the study area were examined.

Quantity, Components, and Value of Waste Materials Landfilled in the United States

SummaryThe current system of production and consumption needs end‐of‐life disposal to function, but the linkage between upstream production‐consumption with the downstream landfill as terminus is, at best, a tenuous, one‐way relationship, suggesting a partial system failure. A starting point to fix this link is to confront, systematically, the messy “black box” that is mixed waste landfilling, interrogate its contents locally, and determine a baseline that can be used to scale up results. Here, we develop a detailed model characterizing landfilled municipal solid waste (MSW) in the United States across the dimensions of material quantity, quality, location, and time. The model triangulates measurements spanning 1,161 landfills (representing up to 95% of landfilled MSW) and 15,169 solid waste samples collected and analyzed at 222 sites across the United States. We confirm that landfilled quantities of paper (63 million megagrams [Mg]), food waste (35 million Mg), plastic (32 million Mg, textiles (10 million Mg), and electronic waste (3.5 million Mg) are far larger than computed by previous top‐down U.S. government estimates. We estimate the cost of MSW landfill disposal in 2015 (10.7 billion U.S. dollars [USD]) and gross lost commodity value of recyclable material (1.4 billion USD). Further, we estimate landfill methane emissions to be up to 14% greater (mass basis) than the 2015 U.S. inventory. By principally relying on measurements of waste quantity and type that are recorded annually, the model can inform more effective, targeted interventions to divert waste materials from landfill disposal, improve local, regional, and national emission estimates, enhance dissipative loss estimates in material flow analyses, and illuminate the dynamics linking material, energy, and economic dimensions to production, consumption, and disposal cycles.

DETERMINATION OF PROPERTIES AND ELEMENTAL COMPOSITION OF MUNICIPAL SOLID WASTE IN ORDER TO PROPOSAL OF WASTE-TO-ENERGY PROJECT IN BINH DUONG PROVINCE

Domestic solid wastes are classified into 10 samples of 04 groups with different sizes: 2 samples with sizes under and over 120 mm (M1-1, M1-2); 2 samples with sizes under and over 80 mm (M2-1, M2-2); 2 samples with sizes under and over 40 mm (M3-1, M3-2); 4 samples with sizes under 40 mm, 40 to 80 mm, 80 to 120 mm and over 120 mm (M4-1, M4-2, M4-3, M4-4). Results of sorting 10 solid waste samples into food, cloth, wood, plastic, paper, rubber/leather, metal, glass, other organic and inorganic components shown that recycled combustible, non-recycled combustible portions are ranged from 15,46 to 93,90 %, from 5,34 to 80,17 %, respectively. The density of 10 compressed garbage samples is ranged from 525,9 to 2016,7 kg/m3; moisture contents are ranged from 18.03 to 20.92 %. Ash content is ranged from 1.12 to 9.49 % dry weight; Calorific value is ranged from 3164,9 to 5757,0 kcal/kg of garbage. The volume of leached water from 10 kg wet garbage pressed by 250 kg load in 2 days is 300 ml (equivalent to 327,1 g). Results of elemental composition analysis shown that the contents of C, H, N, Cl, S are ranged from 35,00 to 51,96, from 6,01 to 6,23, from 0,41 to 0,88, from 0,44 to 0,56, from 0,14 to 0,84 %, respectively. On this basis, the author have proposed a waste-to-energy plant with capacity of 250 tons of waste/day to generate the electricity with capacity of 17,0 MW/day.

Characterization and composition analysis of municipal solid waste in Kano, Nigeria

Municipal Solid Waste (MSW) is produced through human activities and in the last two decades, management of MSW has become a major concern due to considerable increase in its production. The amount of MSW produced increases with economic growth and this demands for efficient solution. This paper reports the characterization and composition analysis of MSW in Kano metropolis. Solid waste samples were collected and analysed from the four major dumpsites in Kano metropolis during the months of September, 2016- January, 2017. The results showed that light plastic had the highest mean values of 8.63kg/50kg sample, Organics 7.22kg/50kg, Heavy plastic 4.15kg/50kg, Fabric 3.91kg/50kg, paper 2.70kg/50kg, metal 2.05kg/50kg, glass 1.89kg/50kg, Bone 1.47kg/50kg, styrofoam 0.19kg/50kg, others 1.06kg/50kg and wood -0.25kg/50kg. There was significant correlation between estimated population and volume of trash collected. We offered suggestion for effective management strategies and efficient policies for waste reduction, disposal and recycling practices. Keywords: Waste Characterization, Municipal Solid Waste, Waste Composition, Kano, Nigeria

TESTING OF 24 POTENTIALLY HAZARDOUS WASTES USING 6 ECOTOXICOLOGICAL TESTS

The ecotoxicological characterization of wastes according to the European Waste List (EWL) is part of their assessment as hazardous or non-hazardous. Despite inclusion in national laws no methodological details have been fixed concerning the hazard property HP 14 (“ecotoxic”).This paper intends to discuss the classification of wastes by ecotoxicological testing, using 24 representative samples of solid wastes (identified by their EWL number) with different properties. They were sampled according to standard methods, and, with one exception (galvanic sludge), ecotoxicologically tested. No chemical investigation of the samples was performed but they were characterized according to their properties in the ABANDA data base. Nearly all of these wastes were “mirror entries” in the EWL (i.e., they can be hazardous or not depending on the concentration of hazardous substances). For the ecotoxicological characterization three aquatic tests with eluates (genotoxicity, Algae, Daphnia) as well as three terrestrial tests with solid wastes (bacteria, plants, earthworms) were conducted. All investigations were performed as limit tests with three dilution steps. Algae, plants and terrestrial bacteria were the most sensitive organisms. Since no waste eluate showed any indication of genotoxicity, the genotoxicity test should be replaced by the luminescent bacteria test (ISO 11348-3). Proposals for toxicity criteria as well as hazard classifications were taken from the literature but they were modified according to own experiences. Using these concentration limits for the classification whether these wastes are ecotoxic or not, and using different versions of the hazard classification approach, 15-19 waste samples out of 23 waste samples were classified as ecotoxic (64-83%). It is proposed to perform a plausibility check of the respective HP 14-classification. The procedure used in this contribution (i.e. sampling of the wastes, their ecotoxicological testing as well as their hazard classification) could form the basis of a standardized hazard classification approach as proposed recently in the literature. In summary, this works confirms that ecotoxicological tests are practical and sensitive in order to be used for the ecotoxicological hazard classification of very different wastes.

Assessment of applicability index for better management of municipal solid waste: a case study of Dhanbad, India

ABSTRACTSelection of suitable municipal solid waste management (MSWM) options is one of the major challenges in urban areas of the developing countries. Success of MSWM requires accurate data of generation rate, composition and physico-chemical characteristics of solid wastes. Improper handling of solid waste can have significant environmental and aesthetical impacts. The present study proposes a new method (applicability index – Pik values) for identifying the most appropriate disposal option with the help of applicability values of Composting-CP, Incineration-IP and Landfill-LP for individual components of MSW based on the results of the physico-chemical analysis of the collected representative solid waste samples from the study area, Dhanbad, India. The mean values of moisture content, carbon, hydrogen, oxygen, nitrogen, sulfur, volatile organic carbon, fixed carbon, ash content, density and calorific values (CV) of individual components were used as input values in this process. Based on the proposed applicability index (Pik), the highest Pik values were obtained for incineration (IP) for plastics, polythene, paper, coconut shell, wood, cardboard, textile, thermocol (polystyrene), rubber, sugarcane bagasse, cow dung and leather wastes (IP > CP > LP) due to high CV of these solid waste components; the highest Pik values were obtained for composting (CP) of kitchen waste (CP > IP > LP); and the highest Pik values for inert wastes were obtained for landfill option (LP > IP > CP). The highest Pik value for a particular waste for a specific treatment option signifies that the waste is suitable for treatment/disposal using that option.

Determination of Commonly Used Pharmaceuticals in Hospital Waste of Pakistan and Evaluation of Their Ecological Risk Assessment

In this study, six human pharmaceuticals in wastewater, sediments, and solid waste samples of five hospitals in Gujrat, Pakistan, were detected by a validated high performance liquid chromatography‐ultraviolet method and then their ecological risk assessment was conducted. The pharmaceuticals include paracetamol, naproxen, diclofenac, ibuprofen, amlodipine, and rosuvastatin and were chromatographed on a C‐18 column at 254 nm using liquid–liquid extraction. The highest concentration obtained was of paracetamol and it was also detected in all the five hospitals and all the sample matrices (max. 696 ng/mL) whereas, the concentration of other pharmaceuticals were also very high although they were not detected in all the sample matrices. Maximum concentrations of other pharmaceuticals detected were naproxen (220 ng/mL), diclofenac (186 ng/mL), ibuprofen (596 ng/mL), amlodipine (303 ng/mL), and rosuvastatin (104 ng/mL). Risk assessment in terms of risk quotient (RQ) was also calculated based on maximum measured concentration and the RQ values were very high for all pharmaceuticals. The maximum RQ values obtained from different pharmaceuticals were paracetamol (696 against daphnia), naproxen (84 against fish), diclofenac (9300 against Oncorhynchus mykiss), ibuprofen (16 000 against Oryzias latipes), and amlodipine (471 against green algae). The results from this study demand for comprehensive monitoring of pharmaceuticals from different points sources and treatment of all type of wastes including hospital waste.

Physicochemical Composition of the Household Solid Waste and Prospect for Biogas Production

Solid waste management is now one of the big challenging issues in Bangladesh. With increasing population, volume of solid waste is increasing enormously. Production of biogas from organic solid waste is an environment friendly energy source as well as great management strategy of solid waste. The purpose of this current study is to determine the physicochemical composition of solid waste to determine the prospect of biogas production. Results reveal that, temperature and pH of the solid waste should be controlled for the maximum production of biogas. On the other hand, collected solid waste samples contained sufficient amount of moisture for the production of biogas. Appropriate temperature controlling system and buffer for pH maintenance can play a great role to maximize biogas production.J. Environ. Sci. &amp; Natural Resources, 9(2): 151-154 2016

Genetic Analysis of Norovirus Strains that Caused Gastroenteritis Outbreaks Among River Rafters in the Grand Canyon, Arizona.

Toilet solid waste samples collected from five outbreaks among rafters in the Grand Canyon were subjected to sequencing analysis of norovirus partial capsid gene. The results revealed that a GI.3 strain was associated with one outbreak, whereas the other outbreaks were caused by GII.5 whose sequences shared>98.9% homology.