Japan and China Joint Symposium Sustainable Sanitation and Environment and Human Health Risk Management Date: October 15th, 2012 Venue: Hokkaido University Conference Hall (学術交流会館) Organizers: Main Organizer: Faculty of Engineering, Hokkaido University Co-organizer: Xi’an University of Architecture & Technology, JST Outline: Poverty is considered to contribute to increased incidence of all waterborne diseases, which in turn perpetuate and exacerbate the cycle of poverty. This symposium will discuss solutions to water and sanitation problems around the world based on achievements made by research groups in Japan and China on the Strategic International Research Cooperative Program implemented by JST. Language: English Program: 12:30-13:00: Registration 13:00-13:15: Opening Session Welcome address by Prof. Naoyuki Funamizu (Faculty of Engineering, Hokkaido University) Opening address by Prof. Xiaochang Wang (Xi’an University of Architecture & Technology) 13:15-14:00:Session1: Urine and its application (Chair: Mr. Charchalac Ochoa) Moustapha Sene: Effect of Human Urine Application Volume in Komatsuna Growth Shanqing Jiang: Characteristics of nitrogen and phosphorus absorption by soil particles for urine disposal and fertilizer production Hideaki Miyai: Investigation into determination method of anti-malarial drugs in agricultural soil and plant assumed as human urine reuse 14:00-15:00:Session2: Pathogen and Toxicity (Chair: Ms.Zhang) Shuji Ozawa: Detection, Quantification and Isolation of Escherichia coli O157 with Flow Cytometry and Fluorescence-Activated Cell Sorting Zhenzhen Yu: Comparison of strain culture and real-time PCR for identification of Escherichia coli in environmental water Takashi Yoshimura: Bacterial extracellular polymeric substances as a novel adsorbent for human noroviruses Maoni Wu: Comparison of bioassays using algae and luminescent bacteria for ecotoxicity assessment of reclaimed water 15:00-15:30: Coffee Break 15:30-16:15:Session3:Gray & Wastewater Treatment (Chair: Mr. Sene) Jialing Tang: Isolation and characterization of membrane fouling substances from a membrane bioreactor Sebastian Ignacio Charchalac Ochoa : Evaluation of Intermittent Sand Filtration for Removal of Greywater-related Micropollutants Yucong Zheng: Comparative study of constructed wetlands of various types for treating polluted river water 16:15-17:15:Session4:Composting (Chair: Ms. Wu) Qian Li : Characteristics of fecal organic decomposition and nitrogen transformation in an aerobic composting reactor with sawdust as bulky matrix under two typical temperatures Natsuru Yamauchi: Investigation on maturing period of compost from composting toilet Yongmei Zhang: Anaerobic digestion of kitchen wastes for the production of carbon source for a membrane bioreactor Rui Tezuka: Inactivation mechanism of pathogenic bacteria using lime and ash in composting toilet 17:15-17:45:Session5: Design (Chair: Mr. Yamauchi) Yosuke Deguchi: Design of resource recycling sanitation system based on relationship between fertilizer demand and potential supply of human excreta as fertilizer in Indonesia Kenta Yabui: Design of composting toilet for practical application in Burkina Faso 17:45-18:00 closing, photo session *One presentation: 10minutes presentation followed by 5 minutes discussion Effect of human urine application volume in Komatsuna growth Moustapha SENE*, Nowaki HIJIKATA*, Ken USHIJIMA*, Naoyuki FUNAMIZU* 1/2/3/4 Department of Environmental Engineering, Hokkaido University. (Kita13,Nishi 8,Kita-ku,Sapporo-shi,Hokkaido,060-8628,Japan) Keywords: Human urine, application volume, agriculture Human urine contains large amount of nitrogen (N), phosphorus (P) and Potassium (K) and can be reuse in agriculture in order to substitute industrial fertilizer. Nevertheless urine contains some salts, pathogen and pharmaceuticals. Considered the salt issue, too much urine application has a potential to inhibit plant growth, since it may cause too much sodium and/or nitrogen accumulation in soil. Therefore, the objectives of this study were to investigate the effect of human urine application volume in Komatsuna cultivation. Pot test was conducted in greenhouse using sandy soil (a) and sandy soil mixed with chaff charcoal compost (b) as media. Considered total nitrogen required to growth “Komatsuna” in (a) (140 mg/pot) and in (b) (28.3 mg/pot). Diluted (1/3) synthetic urine volume application was designed as V0 (34.8 mL/pot) for (a) and V0’ (7.0 mL/pot) for (b) in total 30 days cultivation., 3 different urine treatments volumes and 1 modified Hoagland solution volume (same amount N with plant requirement), those defined as V0, 2V0, 3V0 and Vm-H were applied in different pots in (a). In similar manner V0’, 2V0’, 3V0’, and Vm-H’ were applied in (b). Totally, 4 fertilizer treatments were set in each media and control (5 case/media). 50 experimental pots were used for 10 treatments with 5 replications per condition. Then, plant weight, N concentration in shoot, root and soil were measured. In shoot dry weight of (a), V0 (2.38±0.23 g), 2V0 (2.49±0.88 g), 3V0 (3.10.± 0.43 g) and Vm-H (2.71±0.33 g) had no significant difference but significantly higher than control (0.28±0.23 g) (Turkey Kramer, p<0.05). In the case of (b), shoot dry weight values (V0’) 5.32±0.73, (2V0’) 6.10±0.73, (3V0’) 5.87±0.68 and (Vm-H’) 5.51±0.31 were in the same level but only (2V0’) was higher than (control’) 4.92±0.44 g. Furthermore, N concentration in shoot in (a) were 42.45±2.33 (V0), 63.75±6.22 (2V0), 80.40±1.83 (3V0), 31.74±2.43 (Vm-H) and 10.45±1.73 mg/g plant dry weight (control) and significantly different among them. Besides in (a), N reminded in soil after cultivation for the followed treatments V0, 2V0, Vm-H (0.16±0.02, 0.17±0.01, 014±0.02 mg/g plant dry weight, respectively) was in the same level and significantly lower than 3V0 (0.22±0.01 mg/g plant dry weight). Regarding the (b) case, N reminded in soil after cultivation for all treatment included was statistically in the same level. Moreover in (b), N uptake in shoot (V0’) 30.41±4.56, (2V0’) 31.57±1.47 and (3V0’) 34.41±3.88 mg/g plant dry weight were in the same level but significantly higher than Vm-H’ (22.29±1.89 mg/g plant dry weight). From the results, we concluded that urine volume had no effect for Komatsuna growth. Moreover accumulation of N in soil was not observed. Perhaps, extra N and Na might be leached from the pot in our experimental system. Furthermore, urine volume affects N concentration of Komatsuna in soil (a) but not in soil (b). In soil (a) other nutrients (P or micronutrients likewise Fe, Zn, B and so on) probably supply by compost in soil (b), may limit Komatsuna growth. -1- -2- Characteristics of nitrogen and phosphorus absorption by soil particles for urine disposal and fertilizer production # S.Q. Jiang, X.C. Wang , C. Li Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055 China (E-mail: [email protected]) Keywords: urine; nitrogen and phosphorus absorption; soil particles Background and objectives The current option about the dispose of human excreta is inadequacy for the reason that flush-and-discharge systems require large amounts of water and many investments. Ecological sanitation technology which claims to recover resources such as nutrients, water and energy from human waste and wastewater would be a promising approach (Uno Winblad, 2004). The human urine is of particular interest for which contains most of the nutrients and few disease-producing organisms but makes up less than one percent of the total volume in domestic wastewater. Urine could be separated in a urine diversion dehydrating toilet (UDDT), which can then be treated and used as fertilizer (Katukiza, A.Y., et al., 2012) The aim of the present study was to optimize the recovery nutrients from concentrated urine by air dried soil absorption and ensure minimize ammonia losses in the process. We will also evaluate the nutritional value of the final soil products and discuss the feasibility of its use as an agricultural fertilizer. Materials and methods The urine was collected from the men’s tank of the No Mix system in the office building. During collection and storage under non-sterile conditions, the urea present in the fresh urine was hydrolyzed to ammonium due to microbial activity of the system. The soil for the experiment was excavated from surface 20cm of the ground in the campus and then air-dried outdoor over 2mm sieve to save. Basic phy-chemical properties of the stored urine and the original soil are shown in Table 1. During the first process step, in order to ensure the ammonia volatilization less enough and acid consumption minimum as well, stored urine which adjusted pH to 6,5,4,3 and 2 with 12mol/L hydrochloric acid were concentrated to one-tenth of the original volume and collected the condensate water in lab-scale distillation apparatus, respectively. In the second process step, we alternately dried and milled the mixture of concentrated urine (pH<4) and air-dried soil particles (d<2mm) whose mass ratio 1:2, and detected the absorption status of nutrients in the urine on the soil particles, especially about nitrogen. Table 1 Characteristics of the stored urine and original soil Parameter pH Unite - Stored Urine 9.13 Parameter pH Unite - original soil 8.8 -1 mgNL -1 6172.16 TKN mgNg mgNL -1 5829.21 Water content % Urea mgNL -1 314.45 Water-holding capacity % Ptot mgPL -1 306.03 Ptot mgP2O5g Ktot mgKL -1 2737.42 Ktot mgK2Og TOC mgCL -1 5488 TOC mgCg Ntot + NH4 +NH3 0.3157 1.31 28.5 -1 2.88 -1 20.6 -1 24.9 Results As a result of comparison of the ammonia volatilization rate under the different pH, it was clearly found that the optimum pH adjustment range was pH<4, and the volatilization rate less -3- than 0.4% (Figure1). With the increase of the mixed times, nutrient concentration in the soil productions increase gradually. Contrasted with the idea TKN (Hypothesis non- volatile in the test process) and the actual TKN in the soil productions, the ammonia volatilization rate was about 10%. After 7 times alternately mixed, dried and milled TKN content in the soil production could reach 15% (Figure 2). Referred to the standard of complex fertilizer (GB15063-2009) in China, the total nutrient content (N+P2O5+K2O) in the soil production could up to 25%, which is feasible to use as an agricultural fertilizer. Figure 1 Ammonia volatilization rate under pH between 2 to 6 during the concentration process Figure 2 TKN concentration of the soil during repeated absorption process Conclusion In conclusion, it is a practicable method to recover all nutrients from source-separated human urine and use the production as an agricultural fertilizer by combining concentration and absorption on soil. References Katukiza, A.Y., Ronteltap, M., Niwagaba, C.B., Foppen, J.W.A., Kansiime, F., Lens, P.N.L. (2012) Sustainable sanitation technology options for urban slums – a review. Biotechnology Advances. 30(2012), 964– 978. Uno Winblad (Ed.) (2004) Ecological sanitation (second edition). Stockholm Environment Institute, Stockholm, Sweden. -4- Investigation into determination method of anti-malarial drugs in agricultural soil assumed as human urine reuse 1 1 2 Hideaki. MIYAI* , Nowaki. HIJIKATA , Takashi. KAKIMOTO , Naoyuki. FUNAMIZU 1 2 1 Department of Environmental Engineering, Hokkaido University Department of Water Environment, Center for Environmental Science in Saitama Keywords: urine reuse; anti-malarial drugs; agricultural soil; determination method; LC/MS Although diffusion of appropriate sanitation is one of the big issue in Millenium development goals, one speculation indicates the difficulty in sub-Sahel region in Africa. For this region, it has been expected to introduce an on-site wastewater differentiable treatment system, since the system has advantage for sewer pipe free, water free and recovery of fertilizer components. Several attempts have shown that human urine obtained from the system is available to crops and vegetables as a liquid fertilizer. On the other hands, pharmaceuticals contained in the urine might be widely spread in environment when urine is directly reused. Assumed as urine reuse in sub-Sahel region, behaviors of anti-malarial drugs, which are commonly distributed in the region, in agricultural field should be monitored. However, determination method of anti-malarial drugs in soil has not been developed, so far. In this study, therefore, the determination method using LC/MS and solid phase extraction (SPE) were investigated. Four anti-malarial drugs, chloroquine (CQ), doxycycline (DX), quinine (Q) and artesunate (AS), were focused in this study, since they are highly excreted in urine as unchanged form or commonly distributed in sub-Sahel region. As extract solution from soil, water, methanol and methanol +KCl were compared in the present study. 0.03 mg of anti-malarial drugs were spiked in 10 g of soil mixture (river sand and compost at the ratio of 4:1) and extracted with 30 mL of extract solution by shaking and sonication. The suspension was centrifuged and the supernatant was collected. These procedures were done again. The collected supernatants were filtered through glass filter and set up at 90 ml. Then 30 ml of them were transported in 2000 mL of pure water adjusted pH 2.00±0.05 with HCl. The liquid was load in conditioned SPE cartridge (Oasis HLB, 6 cc/ 500 mg) and washed with 5 mL of pure water. Target compounds in the cartridge were eluted with 5 ml of acetonitrile and 5 ml of mixture of acetonitrile and pure water (1:1). The eluate was filtered and injected into LC/MS system. Separations of the targets were done on a SunFire C18 (2.1 × 50 mm, 3 mm) column with 10 mM ammonium formate in ultrapure water containing 0.3% formic acid and acetonitrile by gradient program. Recovery rate of targets in methanol and methanol +KCl extraction were relatively higher than water extraction. The values of CQ, DX, Q and AS in methanol +KCl extraction were 16±1.3%, 65±2.7%, 80±5.1% and 88±2.7%, respectively, and those in methanol extraction were 9±0.1%, 50±6.3%, 59±0.9% and 90±2.2%, respectively. Recovery rate of CQ, DX and Q in methanol +KCl extraction were significantly higher than that of methanol (t-test, p < 0.05). One reason of high recovery of DX and Q in methanol +KCl extraction might be amide radical, since positive charge of the amide radical would ionically bound with soil. On the other hands, recovery of CQ, which is high log Kow, was not success in the present study. Therefore, extraction with hydrophobic solvent (e.g. acetone, dichloromethane) should be further investigated. -5- -6- Detection, Quantification and Isolation of Escherichia coli O157 with Flow Cytometry and Fluorescence-Activated Cell Sorting S. Ozawa#*, S. Ishii*, S. Okabe* * Division of Environmental Engineering, Faculty of Engineering, Hokkaido university (〒060-8628 North 13, West 8, Kitaku, Sapporo, Hokkaido, Japan) Keywords: E. coli O157; Flow cytometry; Fluorescence-activated cell sorting Several disease incidents have occurred directly or indirectly by drinking water, river water, or recreational water polluted by pathogens. In recent years, enteric diseases caused by the use of polluted irrigation water were reported. Pathogenic bacteria in irrigation water may contaminate vegetables and can cause foodborne diseases. Microbiological safety is also necessary to be verified for reclaimed water that has been used increasingly over the world. Flow cytometry (FCM) and fluorescence-activated cell-sorting (FACS) have been developed as strong tools for detecting, quantifying and recovering microorganisms from aquatic environments. However, it is still challenging to isolate rare pathogens from environmental samples without pre-incubation. Particles in FCM individually flow along laminar sheath fluid. Each particle is irradiated with laser beams, and resulting signals (forward scatter, side scatter, and various fluorescent signals) are monitored. When FCM-FACS is used, particles with specific characteristics are electrically charged, and can be individually sorted by their charge. FCM-FACS has several advantages in environmental microbiology. The use of fluorescentlylabeled antibodies or fluorescent probes enables to detect microorganisms specifically from complex populations. FCM can detect thousands of particles in a second and sort immediately, therefore high throughput assay is available. Cells can be isolated directly from water samples prior to incubation in a medium and bacterial population diversity is preserved. The objective of my study is to develop a method to detect, quantify and isolate rare pathogens from environmental water by using FCM-FACS for estimating contamination source contribution. Optimizing fundamental method by using pure culture samples were implemented. As a result, sufficient amount of antibody was verified. Sorting efficiency from K12 and O157 mixed culture sample (Figure 1) was verified by quantitative PCR (Figure 2, Figure 3). As a future plan, sorting efficiency especially single-cell sorting should be improved. To develop and optimize the method to recover live bacteria from environmental water, several methods reported for aquatic samples and soil samples will be applied. M6 M5 M4 Figure 1 Detection of O157 from K12-O157 mixed cultures by FCM. Samples with different K12/O157 ratio were stained with APC-labeled antibody and FITC-labeled antibody. Horizontal axis means fluorescence from FITC and vertical axis means one of APC. Particles in R2 gate were sorted. M6 contains 52.8%, M5 contains 9.2% and M4 contains 1.1% of O157. -7- M6 77.6% M5 55.1% M4 33.2% Figure 2 Detection rate (i.e. detected O157 cell numbers by qPCR divided by sorted O157 cell numbers) from different ratio of K12 and O157 mixed sample in Figure1. Detection rate was converted based on regression line of colonial PCR (Figure 3). The data over 100% after conversion was considered as 100%. Error bar shows difference between results of duplicated wells. Figure 3 qPCR result of O157 added as control. Horizontal axis shows Log10 O157 cell numbers added as control and vertical axis shows Log10 O157 cell numbers detected by qPCR. Detection rate (i.e. detected O157 cell numbers divided by added O157 cell numbers) were 37.8 % in average References Tani, K. and Nasu, M. (1999) Escherichia coli O157 in Natural River Water, Microbes and Environments. 14(2), 101-105 Centers for Disease Control and Prevention. (2006) Update on Multi-State Outbreak of E. coli O157:H7 Infections From Fresh Spinach, October 6 Biegala, I., & Not, F. (2003). Assessment of picoeukaryotes in the natural environment by using taxonspecific oligonucleotide probes in association with tyramide signal amplification-fluorescence. Applied and Environmental Microbiology, 69(9), 5519. Tanaka, Y., Yamaguchi, N., & Nasu, M. (2000). Viability of Escherichia coli O157:H7 in natural river water determined by the use of flow cytometry. Journal of Microbiological Methods, 228–236. Picot, J., Guerin, C. L., Le Van Kim, C., & Boulanger, C. M. (2012). Flow cytometry: retrospective, fundamentals and recent instrumentation. Cytotechnology, 64(2), 109–30. Ferrari, B. C., Winsley, T. J., Bergquist, P. L., & Dorst, J. V. (2012). Flow Cytometry in Environmental Microbiology: A Rapid Approach for the Isolation of Single Cells for Advanced Molecular Biology Analysis. Methods in Molecular Biology, 881, 3–26. -8- Comparison of strain culture and real-time PCR for identification of Escherichia coli in environmental water # J H Zhou*, X C Wang *, Z Ji*, L M Xu*, Z Z Yu* * Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055, P.R. China # Corresponding author, E-mail: [email protected] Keywords: culture method; real-time PCR; Escherichia coli This study compared a membrane filtration method on MFC agar/culture method and a realtime PCR method to detect Escherichia coli (E. coli) in environmental water. Real-time PCR detection method is incapable of distinguishing between viable and non-viable pathogenic microorganisms while culture method can detect the viable cells. And the influent of Siyuan sewage system and the effluent of MBR were collected to prepare experiment water samples. The E. coli was spiked into water samples as bacterial tracer. The concentration of E. coli was detected both by culture method and real-time PCR. We used 7 concentration gradient of recombinant plasmid as template proceeding real-time PCR, then we could get the standard curve as shown Figure 1.1. The result indicated that 0 6 2 good linear relation was between 10 and 10 copies/µL and R was around 0.993. The detection limit was less than 5 copies/µL. As a result of comparison of the different water samples, we can conclude that different water quality has different influences on recovery rate. The recovery rate of high turbidity of water was 37.3% while that of low turbidity was 63.9% during the protocol of real-time PCR detection. The water samples obtained from the MBR effluent was treated with different pore size membranes and the results were shown in Figure 1.2. It was found that the differences of the E. coli concentration between two methods were found obviously variation with 0.22 µm membranes, whereas the variations were relatively slight when the samples passed through 0.45 µm and 0.65 µm membranes, respectively. We can conclude that different treatments have different influences on the detection of E. coli by two methods. Comparing the result of three parallel tests, the variation of culture method was smaller than that of real-time PCR. The concentration of coagulant added into water samples also had influences on E. coli removal efficiencies and the consequence we could infer from Figure 1.3. It was clear that the removal efficiencies were increased with the increase of concentration of coagulant. The concentration of E. coli measured by culture method was ten times higher than that of realtime PCR. Figure 1.1 Standard curve of real-time PCR -9- Concentration (copies/L) 1.E+06 MFC-Culture Real-time PCR 1.E+05 1.E+04 1.E+03 1.E+02 0.22 μm (a) 1.E+06 MFC-Culture Real-time PCR 1.E+05 1.E+04 1.E+03 Concentration (copies/L) Concentration (copies/L) 1.E+06 1.E+02 MFC-Culture Real-time PCR 1.E+05 1.E+04 1.E+03 1.E+02 0.45 μm 0.65 μm (b) (c) Figure 1.2 Concentration of E. coli treated with different pore size of membranes Concentration (copies/L) 1.E+06 MFC-Culture Real-time PCR 1.E+05 1.E+04 1.E+03 1.E+02 2 mg/L 5 mg/L 8 mg/L 10 mg/L 15 mg/L Figure 1.3 Concentrations of E. coli after using coagulant References Ahmed, W., Tucker, J., Bettelheim, K.A., Neller, R. & Katoulia, M. (2007) Detection of virulence genes in Escherichia coli of an existing metabolic fingerprint database to predict the sources of pathogenic E. coli in surface waters. Water Res, 41, 3785 – 3791. Maheux, A. F., Be´Rube´, E., Boudreau, D. K., Cantin, P., Boissinot, M., Bissonnette, L., Rodrigue, L. & Bergeron, M. G. (2011) Ability of three DNA-based assays to identify presumptive Escherichia coli colonies isolated from water by the culturebased mFC agar method. Water Res, 45, 26382646. O’hanlon, K. A., Catarame, T.M.G., Blair, Ian. S., Mcdowell, D. A. & Duffy, G. (2005) Comparison of a real-time PCR and an IMS/culture method to detect Escherichia coli O26 and O111 in minced beef in the Republic of Ireland. Food Microbiol, 22, 553–560. Toze, Simon (1999). PCR and the detection of microbial pathogens in water and wastewater. Water Res, 33, 3545-3556. -10- Bacterial Extracellular Polymeric Substances as a Novel Adsorbent for Human Noroviruses T. Yoshimura#*, D. Sano*, A. Suenaga*, T. Miura*, S. Okabe* *Division of Environmental Engineering, Faculty of Engineering, Hokkaido university (〒060-8628 North 13, West 8, Kitaku, Sapporo, Hokkaido, Japan) Keywords: human noroviruses, enteric bacteria, extracellular polymeric substances Human norovirus is one of the leading causes of infectious gastroenteritis worldwide, and it has been estimated that up to 200,000 deaths of children are caused by noroviruses in developing countries. For the sake of preventing the infection caused by norovirus, it must be effective to reveal the lifecycle of norovirus and to shut the infectious route of noroviruses. However, the actual infectious ruotes of noroviruses in human society including water environments have remained to be elucidated. In this study, we paid attentions to the two scientific facts concerning noroviruses and some bacteria and hypothesized that some human enteric bacteria can specifically capture human norovirus particles. One scientific fact as the key of this study is an interesting characteristic about the way of norovirus infection. Some recent studies showed that histo-blood group antigens (HBGAs) are exploited by human norovirus as cellular receptors in the infection to human gut epithelial cells. Another important scientific fact is about the characteristic of the substances existing on the surface of some bacteria. It has been proved that some human enteric bacteria have similar structure to human HBGAs on their outer surface. Based on these scientific facts, we hypothesized that human noroviruses recognize bacterial HBGA-like substances as well as human HBGA. If this hypothesis is correct, there is a possibility that norovirus bounded to those HBGA-positive bacteria can be protected from the external stimuli, including disinfection in water treatment processes and sunlight radiation. In order to elucidate these hypotheses, it is necessary to clarify the binding characteristic of noroviruses to those HBGA-positive bacteria. In our laboratory, human enteric bacteria which contain larger amount of HBGAs were isolated. The binding between the strain registered as Enterobacter sp. SENG-6 and norovirus-like particles (NoVLPs) were confirmed by transmission electron microscopy (TEM) (Figure 1), in which NoVLPs were observed mainly in their capsular region. Based on this result, extracellular polymeric substances (EPS), consisting of the capsular, was extracted from this strain and two other strains (Escherichia coli K12 and Staphylococcus epidermidis ATCC 35984), and HBGA-like substances which bound to NoVLPs were detected by enzyme-linked immunosorbent assay (ELISA). As a result, blood group A antigen-like substances were detected from EPS (Figure 2), and it can be said that human norovirus may recognize the A-like substances included in bacterial EPS by the same way as the recognition of human HBGA as their binding site. The binding affinity between NoVLP and EPS was confirmed by quartz crystal microbalance (QCM). The significant affinity was observed in the binding between NoVLP GII.6 and EPS from Enterobacter sp. SENG-6. The binding constant was estimated to be larger than 3.1 x 6 -1 10 [M ] when Langmuir type binding is assumed. This value was quite similar to that of 6 9 antigen-antibody reaction (10 -10 ), so it seemed that the binding between norovirus and the EPS can be significant even in water environments. -11- NoVLP GII.6 Figure 1 TEM image of the binding between NoVLP GII.6 and Enterobacter sp. SENG-6 (x 20,000). 4 A-like substances B-like substances Relative absorbance O(H)-like substances 3 2 1 0 Enterobacter sp. SENG-6 E.coli K12 S. epidermidis ATCC 35984 Figure 2 ELISA for the binding of HBGA-like substances in EPS from each strain of bacteria with GII. 6 NoVLP. References Ming et al. 2005. Norovirus and its histo-blood group antigen receptors: an answer to a historical puzzle. Trends Microbiol. 13: 285-293 Nasir et al. 2009. A study of norovirus-HBGA interactions. Chalmers University of technology, University of Gothenburg. Springer et al. 1961. Blood Group Activity Of Gram-Negative Bacteria. J. Exp. Med. 113: 1077-1092 Huang et al. 2003. Norovirus Bind to Human ABO, Lewis, and Secretor Histo-Blood Group Antigens: Identification of 4 District Strain-Specific Patterns. The Journal of Infectious Disease. 188: 19-31 -12- Comparison of bioassays using algae and luminescent bacteria for ecotoxicity assessment of reclaimed water # Maoni Wu, Xiaochang Wang , Xiaoyan Ma Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055 China # Corresponding author, E-mail: [email protected] Keywords: Chlorella vulgaris; Ecotoxicity; Reclaimed water system Generally speaking, water recycling is that wastwater was treated to achieve the standard of reuse. The standard must meet health, people sensory,equpment structure demands.However, the standard excluded ecotoxicity of reclaimed water.What’s more, ecotoxicity of residual trace toxic substances in reclaimed water is unknow.So in this paper, in order to evaluate ecotoxicity of reclaimed water,a reclaimed water recycle system was set up in a campus. In the reclaimed water recycle system,three lakes and a wasterwater treatment 2 with an A O biological unit and a MBR were set up. The influent of wasterwater treatment was a mixture f black water from toilet flushing, grey water from miscellaneous uses,and kitchen wastewater from the university anteens. The effluent from the MBR was suppied to three lakes which played both the functions of landscaping and storage reservoirs where the water was further supplied to buildings for toilet flushing and to the green belt for gardening and irrigation. In the research, ecotoxicity of MBR effluent and three lakes were detected. Inhibition test with alga growth was the important method to detect ecotoxicity in research. Ecotoxicity of four reclaimed water were detected using Chlorella vulgaris, which reflects the changes of ecotoxicity in reclaimed water recycle system, and compared with luminescent bacteria test. Figure 1 the relationship between standard substances with inhibition according to Chlorella vulgaris test 100 60 40 20 0 60 40 20 -20 0 0 100 200 300 400 100 1 2 60 40 20 0 0.1 0.2 0.3 Concentration of Cu (mg/L) 0.4 20 0 0.1 0.2 0.3 0.4 0.5 Concentration of Ni (mg/L) 100 y = 550.2x + 37.69 R² = 0.838 60 40 20 0 0 40 Concentration of Zn (mg/L) Inhibition(%) Inhibition(%) 80 y = 188.3x + 30.25 R² = 0.996 60 3 80 y = 319.7x + 3.900 R² = 0.992 80 0 0 Concentration of Phenol (mg/L) Inhibition(%) 100 y = 18.56ln(x) + 63.2 R² = 0.986 80 Inhibition(%) y = 0.255x - 0.803 R² = 0.997 80 Inhibition(%) Inhibition(%) 100 80 y = 275.6x + 39.03 R² = 0.891 60 40 20 0 0 0.02 0.04 0.06 Concentration of Cr(mg/L) 0 0.1 0.2 0.3 Concentration of Cd (mg/L) Six standard substances was deteceted with Chlorella vulgarris, which included Phenol, Zn (ZnSou4. 7H2O), Ni (NiCl2. 2H2O), Cu (CuSou4), Cr (K2Cr2O7), Cd (CdCl2). In fig.1, there is 2+ an index relationship between Zn and inhibition and other have a good linear relationship with inhibition. -13- Table 1 Standard substances detection with Chlorella vulgaris and Q67 Zn 2+ Cu 2+ Cd 2+ Cr 6+ 2+ Ni Substances Phenol 1227 EC50(mg/L) 199 0.49 0.14 0.04 0.02 0.10 Q67 EC50(mg/L) 222 0.80 2.74 0.40 2.71 ----- 1227- Chlorella vulgaris ; Q67-Vibrio-qinghaiens Table2 The comparison between inhibition test with Chlorella vulgaris and bacterial test with Q67 Quantity 5 2.0×10 L/ d 5 2.0×10 L/d 0L/d 0L/d Weather EC50(Times) MBR H1 H2 H3 1227 13.53 8.89 7.12 — Q67 13.75 10.47 13.1 7.56 1227 10.86 5.04 5.05 4.04 Q67 — — — — 1227 7.72 4.95 4.62 3.67 Q67 10.75 — — 17.54 1227 12.22 9.92 5.4 6.21 Q67 12.26 7.14 23.39 13.86 Rainy Sunny Sunny Sunny 1227- Chlorella vulgaris ; Q67-Vibrio-qinghaiensis; —Stimulate growth ; H1: lake 1; H2: lake 2; H3: lake 3; Quantity: Quantity of water intake to lakes The result shown that reclaimed water without concentration had no ecotoxicity, but concentrated water by revise osmosis has inhibition to the growth of chlorella vulgaris; MBR effluent in the reclaimed water recycle system was good stability and lowest ecotoxicity; among three lakes, the largest influence from the weather was lake 3, and ecotoxicity of lake 3 was highest. Algae test with chlorella vulgaris is much sensitive than luminescent bacteria test with Q67 by detecting standard substances and reclaimed water in reclaimed water recycle system. References State Environmental Protection Administration, Detection of water and wastewater analysis, Fourth Ed., China Environmental Science Press, Beijing, 2002 (in Chinese). OECD guidelines for the testing of chemicals, freshwater alga and cyanobacteria, growth inhibition test, 2006. Lin J. H., Kao W. C., Tsai K. P., Chen C. Y.(2005), A novel algal toxicity testing technique for assessing the toxicity of both metallic and organic toxicants, Water Res., 39, 1869-1877. Liu Q., Zhang X.F., Li T.W., Su X.R.(2006), Effects of light on growth rate, chlorophyll level and cell cycle in four alga species, Journal of Da Lian fisheries university. 21(1), 24-30. Jayne F. R., Roger V. E., Oliver R. P. Toxicity of haloacetic acids to freshwater algae. Ecotoxicol. Environ. Saf.73 (2010) 56–61 -14- Isolation and characterization of membrane fouling substances from a membrane bioreactor # Y.S. Hu*, X.C. Wang *, Y.M. Zhang*, Y.Y. Li**, H. Chen*, P.K. Jin* *Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055, P.R. China ** Graduate School of Environmental Studies, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan *Corresponding author, E-mail: [email protected] Keywords: A-A-O-MBR process; Extracellular polymeric substances; membrane fouling Membrane fouling is one of the barriers for MBR application which not only influences effluent quality, but also increases operation cost. However, it is a complex process and caused by many factors. EPS are the main foulants which make up of many other substances such as protein and polysaccharides, so it is representative and meaningful to study EPS. What’s more, EPS are produced and can also be utilized by microorganisms, which may contribute to membrane fouling control by providing proper conditions. To understand the membrane foulants (EPS in this study) and their characters, a full scale anaerobic-anoxic-oxic (A-A-O) biological unit followed by a submerged MBR for reclaimed 2 water production was studied. Under a constant flux of 16L/m h, TMP varied narrowly between 12 and 22 kPa in 9-month duration with only enhanced flux maintenance (EFM) operation and high effluent quality. Extracellular Polymeric Substances (EPS) in liquids at different steps was isolated and analyzed, it was found that both protein and polysaccharide concentrations decreased along the A-A-O-MBR train, and there was no apparent EPS accumulation as time elapsed, which indicate that microorganisms can produce and utilize EPS. To analysis the change of foulants in sludge, the variation tendencies of humic-like substances and protein in SEPS were demonstrated by Fluorescent excitation-emission matrix (EEM) and the results showed that these substances did not seem to accumulate on/in the membrane and caused obvious membrane fouling. And the protein can be utilized in anaerobic or anoxic conditions, and produced in aerobic conditions, and can be completely separated by membrane which causes the membrane fouling. While humic-like substances change a little and can be consumed in a very limited scale. To understand the foulants on membrane, SEM was used to observe the membrane, it was found that a thin cake attaches on membrane and cannot be removed by routine aeration, while this fouling cake may contribute to avoid membrane fouling. Fourier transform infrared spectroscopy (FTIR) was used to analyze this fouling cake and demonstrated that proteins, polysaccharides, humic acid and other substance with hydroxyl and amino groups are the main foulants. As a kind of main membrane foulants, EPS in solution and sludge have different behaviors, because, in solution, the concentrations decrease along the system, while in sludge, they change with the conditions. Microorganic activities have an important impact on EPS production and consumption. So to control membrane fouling, proper conditions and operation are very important. -15- 1000 400 B 300 A 220 220 300 400 500 Em. Wavelength [nm] 550 450 (b) Ex. Wavelength [nm] 450 (a) Ex. Wavelength [nm] Ex. Wavelength [nm] 450 400 B 300 A 220 220 300 400 500 Em. Wavelength [nm] (c) 400 B 300 A 220 220 550 300 400 500 Em. Wavelength [nm] 550 -100 1000 (d) B 300 220 220 A 300 400 500 Em. Wavelength [nm] 550 400 450 (e) Ex. Wavelength [nm] 400 450 Ex. Wavelength [nm] Ex. Wavelength [nm] 450 B 300 220 220 A 300 400 500 Em. Wavelength [nm] 550 400 (f) B 300 220 220 A 300 400 500 Em. Wavelength [nm] 550 -100 Fig. 1. EEM spectra of influent, SEPS and effluent. (a) Influent; (b) SEPS of anaerobic tank sludge; (c) SEPS of anoxic tank sludge; (d) SEPS of oxic tank sludge; (e) SEPS of membrane tank sludge; (f) Effluent. References S. Judd, The MBR Book: Principles and Applications of Membrane Bioreactors in Water and Wastewater Treatment, Elsevier, Oxford, 2006. Y. Miura, Y. Watanabe, S. Okabe, Membrane fouling in pilot-scale membrane bioreactors (MBRs) treating municipal wastewater: Impact of biofilm formation, Environ. Sci. Technol. 41 (2) (2007) 632-638. Z. W. Wang, Z. C. Wu, G. P. Yu, J. F. Liu, Z. Zhou, Relationship between sludge characteristics and membrane flux determination in submerged membrane bioreactors, J. Membr. Sci. 284 (2006) 87-94. Z. W. Wang, Z. C. Wu, S. J. Tang, Extracellular polymeric substances (EPS) properties and their effects on membrane fouling in a submerged membrane bioreactor, Water Res. 43 (2009) 2504-2512. R. S. Trussell, R. P. Merlo, S. W. Hermanowicz, D. Jenkins, The effect of organic loading on process performance and membrane fouling in a submerged membrane bioreactor treating municipal wastewater, Water Res. 40 (2006) 2675-2683 J. P. Crou, M. F. Benedetti, D. Violleau, J. A. Leenheer, Characterization and copper binding of humic and nonhumic organic matter isolated from the South Platte river: evidence for the presence of nitrogenous binding site, Environ. Sci. Technol. 37 (2003) 328-336 -16- Evaluation of Intermittent Sand Filtration for Removal of Greywater-related Micropollutants: UV Filter Compounds S. Charchalac#*, K. Ushijima**, N. Hijikata**, N. Funamizu** * Graduate School of Engineering, Hokkaido University, Japan (e-mail: [email protected]) ** Faculty of Engineering, Hokkaido University, Japan Keywords: greywater reuse; UV filters; intermittent sand filtration Reuse of used water is recognized as a necessity rather than an option for a large population worldwide. Decentralized greywater treatment systems have focused on achieving discharge/reuse levels pertaining to standard organics and nutrients (Revitt et al., 2011), however, emergent micro-pollutants and other xenobiotic organic compounds –XOCs– will potentially play an important role in the reuse of wastewater (Hernandez et al., 2011). Intermittent sand filters –ISFs– equipped with geotextile filters have been evaluated previously (Charchalac et al., 2011) as a strong alternative to reclaim domestic greywayer from laundry and shower sources by reducing organics and nutrients to low levels but have not been evaluated for micropollutants. Researchers have claimed the importance of such systems as a barrier to remove specific XOCs from reaching environment (Revitt et al., 2011). UV compounds are among many of the emergent pollutants that might increase in concentration in greywater effluents; they were designed to protect human skin from solar UV radiation and to be used in sunscreen products but are increasingly being included in other personal care products such as shampoos, moisturizing creams, lipsticks and others. Some of these compounds might have potential effects on crops and agricultural fields. Four organic UV filter compounds were selected to be evaluated based on type, market use and the hydrophobic/hydrophilic characteristics (Table 1.1). Table 1.1 Selected UV Filter Compounds Type Compound CAS No. MW(g/mol) LogKow Max% * Aminobenzoic acid 4-p-Aminobenzoic acid (PABA) 150-13-0 137.14 0.83 15% Benzophenones Benzophenone 3 (BP3) 131-57-7 228.24 3.79 6% Cinnamate Ethylexyl methoxycinnamate (OMC) 5466-77-3 290.4 5.8 7.50% Photostabilizer Octocrylene (OC) 6197-30-4 361.49 7.35 10% *Standards form USDA Six intermittent sand filters were prepared with different configurations regarding depth, media size and layers (Table 1.2) and operated for 4 continuous months. All the ISFs were equipped with geotextile (polypropylene nonwoven needle-punched fibers; pore size 0.14 mm) above the sand surface to remove suspended solids. Table 1.2 Configuration of ISFs Sand Media Layers and Particle Size (d10>) ISF Column Depth 0-20 cm 20-40 cm A B C D E F 0.60 mm 0.60 mm 0.60 mm 0.90 mm 0.90 mm 0.60 mm 0.30 mm 0.60 mm 0.60 mm 40-60 cm 0.30 mm The influent greywater consisted of a 40:60 mixture of laundry and shower effluents collected from a single person daily use of a selected set of personal care products. Hydraulic 2 loading rate was a daily 16 ml/cm split into three equal discharges (9 AM, 1 PM and 6 PM). -17- Parameters (TSS, COD, TP, TN) were measured following standard methods and the reduction rates in the Intermittent Sand Filters were observed to evaluate biological activity. UV Filters were determined by solid phase extraction and liquid chromatography coupled with a mass spectrometer following a method developed to detect them in environmental samples (Bratkovics et al., 2011). UV filter compounds were all spiked directly from >99% purity products supplied by chemical companies for a target concentration of 1 ppm in the LLGW. Figure 1.1 Removal of UV Compounds by ISFs After spiking UV compounds for an average concentration of 1 ppm in greywayer, only PABA was recovered in concentrations similar to the expected, the other three compounds were measured in significant lower concentrations, which resemble the theoretical maximum dissolved concentration according to the USEPA EPISuite 2011. This means that a part of the spiked compounds precipitated into a solid due to its hydrophobic nature and was most likely removed by simple filtration. Figure 1.2 Removal of UV Compounds by ISFs Regarding the removal of the dissolved part of the hydrophobic compounds, the concentration reduced above 91% even in the shallowest ISF-A (20 cm), whereas the removal of the hydrophilic one (PABA) was noticed to be better with the increase of depth. Probably the major mechanism is the attachment of the hydrophobic compounds to the sand surface, however the biodegradation and final fate of these compounds in the sand, as well as the interactions with surfactants are still unclear. In conclusion, ISFs showed a very good performance in removing these compounds under the limit of detection in this experiment (0.01 ppm concentration - 99.99% removal). References Bratkovics, S. and Sapozhnikova, Y., (2011) Determination of seven commonly used organic UV filters in fresh and saline waters by liquid chromatography-tandem mass spectrometry. Analytical Methods. 3, 2943-2950. Charchalac. S. (2011) Treatment of LLGW by Intermittent Sand Filter and Geotextile Filter. M.Sc. thesis. Div. Env. Eng. Univ., of Hokkaido, Japan. Hernandez, L., Vieno, N., Temmink, H., Zeeman, G., and Buisman, C. (2010) Occurrence of Xenobiotics in Gray Water and Removal in Three Biological Systems. Env. Sci. Tech. 44, 6835-6842. Revitt, D., Eriksson, E., and Donner, E. (2011) The implications of household greywater treatment and reuse for municipal wastewater flows and micropollutant loads. Water Research. 45, 1549-1560. -18- Comparative study of constructed wetlands of various types for treating polluted river water 1 #1 1 1 Y.C. Zheng , X. C. Wang , J.Q. Xiong , Y.J. Liu , Y.Q. Zhao 2 1 Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055 China 2 School of Civil, Structural and Environmental Engineering, University College Dublin, Belfield, Dublin 4, Ireland # Corresponding author, E-mail: [email protected] Keywords: Comparative study; constructed wetland; polluted river water Abstract With intensive urbanization and rapid industrialization in recent decades, surface water pollution has become a series issue in China. Therefore, finding appropriate ways for improving urban river water quality is highly desirable in many cities. Due to their low cost, simple operation and maintenance, and favorable appearance, constructed wetlands (CWs) are considered to be a very promising technology for various wastewater treatments. The CWs can be constructed in different types such as free water surface (FWS), horizontal subsurface flow (HSSF), and vertical flow (VF) wetlands. In fact, each type of the CWs has its own advantage and disadvantage. Furthermore, the design and operation of the CWs have to deal with circumstances much different from the others wastewater treatment plants. In this study, pilot CWs with different combinations of surface- and subsurface-flow stages were constructed and operated for treating the polluted river water in a northwestern megacity in China. The objectives of the study were to compare the performances of different CW systems and to recommend the most appropriate system for the design and construction of the full scale CWs for treating the polluted stream water. Fig. 1 Photos of the pilot CWs and the flow diagram Five pilot CWs were constructed in the flood land near the confluence of the urban stream to the main river channel. Each CW system has similar substrates and similar plants but different configurations with combination of surface- and subsurface-flow stages as shown in 3 Fig. 1. The total flow of the five CW systems was 350 m /d on average which corresponded to 3 2 an average HRT of 3.72 d and an average surface loading of 0.051 m /m ∙d. The construction of the pilot CWs was completed in August 2010. After 3 months trial operation, they were turn to continuous operation. In the period from November 2010 to October 2011, water samples were collected weekly from the influent, effluent, and water at the outlet of each stage of these CWs. After sampling, the samples were sent to the laboratory and chemical analyses were conducted within 24 h regarding suspended solids (SS), organic contents (COD and BOD5), -19- different forms of nitrogen (TN, NH3-N, NO3-N and NO2-N) and total phosphorus (TP). Standard methods were referred for the chemical analyses (APHA, 1998). The annual average concentrations of SS, COD, BOD, NH3-N, TN and TP were 280.0 mg/L, 325.4mg/L, 104.7 mg/L, 29.9mg/L, 39.6 mg/L and 3.9 mg/L, respectively, indicating a very seriously polluted condition of the river water. During a one-year operation of the five CW systems, though differed each other in the combination of VF, HSSF, and FWS stages, average HRT and surface loading, they did not show much differences in the removals of SS (about 90%), COD (about 70%) and BOD (about 93%). The suspended COD and BOD5 removal was closely related to the suspended solids removal. It seems clear that the aerobic/anoxic states would be a key factor governing nitrification and denitrification. The scheme of pure subsurface-flow seems not to be advantageous for treating the polluted stream water from the viewpoint of nitrogen removal due to its relatively high surface loading which restricted a provision of sufficient DO for nitrification as the important first step for nitrogen removal, nevertheless the shortage of DO seems to be favorable for denitrification. The pure surface-flow CWs in this study could perform nitrification and denitrification well because through the free water surface oxygen would be transferred to the upper substrate layer to form an aerobic zone while the bottom substrate layer could be with low DO concentration so as to form an anoxic or anaerobic zone. TP removal increased as the surface loading decreased, this indicates that chemical precipitation under the action of hydroxides might play the main role. As in the case of sedimentation, surface loading would be an important parameter affecting the process of precipitation. The SS removal tended to be much less temperature dependent than the other pollutants while the influence of water temperature was very strong for the removal of NH3-N and followed by the removals of COD, TN, and TP. The influence of water temperature on the removal of BOD was not as stronger as the formers, possibly due to the good treatability of the biodegradable organic matter in the stream water. Through the one-year study of the five pilot CW systems with different combination of surface- and subsurface-low stages, it was verified that SS, organic substances, nitrogen and phosphorus could be effectively removed from the polluted urban stream water by CWs constructed on the flood land near the confluence of the stream to the large river. As the polluted urban stream water contains large quantity of suspended substances, there is always a fear of clogging of the substrate bed. Comparing with subsurface-flow CWs, the surface-flow CWs are more advantageous for preventing bed clogging and more suitable to be placed in the first stage in a hybrid CW system. A surface-flow followed by a subsurface-flow CWs system would be a suitable option for treating the highly polluted river water. References APHA (1998), Standard Methods for the Examination of Water and Wastewater, twentieth edition. American Public Health Association / American Water Works Association / Water Environment Federation, Washington DC, USA. Bu, H.M., Tan, X.A., Li, S.Y., Zhang, Q.F. (2010). Temporal and spatial variations of water quality in the Jinshui River of the South Qinling Mts., China. Ecotoxicology and Environmental Safety 73, 907–913. Faulkner, S.P., Richardson, C.J. (1989). Physical and chemical characteristics of freshwater wetland soils. In: Hammer, D.A. (Ed.), Constructed Wetlands for Wastewater Treatment, Municipal, Industrial and Agricultural. Lewis Publishers, Chelsea, MI, pp. 41–72. Guo, L. (2007). Ecology-Doing battle with the green monster of Taihu Lake. Science, 317 (5842): 1166. Hammer, D. (1989). Constructed Wetlands for Wastewater Treatment: Municipal. Industrial and Agricultural. Lewis Publishers. IWA (2000). Constructed Wetlands for Pollution Control: Processes, Performance, Design and Operation. IWA Publishing, London, 156 pp. Kadlec, R.H., Reddy, K.R. (2001). Temperature effects in treatment wetlands. Water Environ. Res. 73 (5), 543–557. Shutes, R.B.E. (2001). Artificial wetlands and water quality improvement. Environ. Int. 26, 441–447. -20- Characteristics of fecal organic decomposition and nitrogen transformation in an aerobic composting reactor with sawdust as bulky matrix under two typical temperatures Q. Li, X.C. Wang *, H.L. Shi, T. Hu Key lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an, shaanxi Province, 710055, China *Corresponding author, E-mail: [email protected] Keywords: aerobic composting; nitrogen transformation; microbial communities Aerobic composting has been recognized as an applicable method for sanitary disposal of human feces in a bio-toilet system, this treatment transforms organic waste into substances of safe and stabilized states, thus serving as agriculture fertilizer. Temperature as a key factor for composting processes affect the composting reaction on microbial activity and population o structure. In this study, using sawdust as bulky matrix, under two typical temperatures (35 C o and 55 C), the characteristics of fecal organic decomposition, nitrogen transformation and microbial communities were discussed over two-week aerobic composting. The composing reactor used in this study is showed in Fig.1. Air outlet Agitating blade Agitator shaft Composting reactor(30L) Motor Air heater with the temperature controller Water-cooling device Bottom diffuser Exhausted air Flow meter (1m3/h) Air pump Sodium hydroxide solution Sulfuric acid solution Fig.1 Diagram of the experimental composting reactor Taking COD content as the indicator of the fecal organic matter, the result showed that thermophilic composting could speed up hydrolysis process which partly converted nonsoluble degradable organic matter into soluble substances lead to the soluble COD concentration increasing quickly at the initial stage, and the total removal was higher in the first 4 days than that under mesophilic condition. The main way of total nitrogen (TN) loss was organic nitrogen (Norg) ammonification and o ammonia emission. The mesophilic condition of temperature at 35±2 C was beneficial for ammonifying bacteria growing, and organic nitrogen could be converted into ammonium effectively under the action of ammonifying bacteria. Therefore, the sufficient increase of ammonium (NH4-N) concentration could be observed due to the conversion from Norg. TN loss -1 -1 -1 was 12.71 g·kg (9.74g·kg of Norg, 3.23g·kg of NH4-N), it balanced the amount of ammonia release (11.65 g/kg). Under thermophilic condition, ammonification processes were inhibited -21- due to the high temperature, more organic nitrogen could not be converted into ammonium, -1 and still retained in the compost, the final TN loss was 5.66 g·kg mainly contributed by -1 ammonia emission (4.76 g·kg ). Therefore, thermophilic composting was beneficial for nitrogen retaining. During composting process, pH was an important factor on nitrogen loss. In mesophilic composting, pH decreased at the first 2 days due to the formation of low molecular weight fatty acids with organic matter degradation, while increased quickly with organic acids + decomposition and NH4-N formation. With the pH increasing, the equilibrium (NH4 + OH → NH3 + H2O ) shift towards right and the NH3(g) quickly released in mesophilic composting. Under thermophilic condition, there was no sufficient pH increasing in the composting process may due to the inhibited ammonification process in which Norg could be converted into NH4-N. The NH3 (g) emission was also affected by pH which was still below 7 in composting process. The diversity of microbial communities increased under both two temperatures, but the succession processes were different. The typical fecal pathogens such as Coprococcus, Escherichia and Enterococcus in initial compost died out in the composting process under both two conditions due to the high temperature and aerobic environment. The development of microflora in mesophilic and thermophilic composting may contribute to the difference in organic matter degradation. References Bai, F., Wang X.C., 2010. Nitrogen-retaining property of compost in an aerobic thermophilic composting reactor for the sanitary disposal of human feces. Frontiers of Environmental Science and Engineering in China.4(2), 228- 234. Lopez Zavala, M.A., Funamizu, N., Takakuwa, T., 2004. Temperature effect on aerobic biodegradation of feces using. Water Research. 38, 2406- 2416. Maeda, K., Hanajima, D., Morioka, R., Osada, T., 2010. Characterization and spatial distribution of bacterial communities within passively aerated cattle manure composting piles. Bioresource Technology. 101, 9631- 9637. Stentiford, E.T., 1996. Composting control: principles and practice. The Science of Composting. Chapman Hall, 49- 59. Vitousek, P.M., Aber, J.D, Howarth, R.W., Likens, G.E., Matson, P.A., Schindler, D.W., Schlesinger, H.W., Tilman, D.G., 1997. Human alteration of the global nitrogen cycle: sources and consequences. Ecological Application. 7(3), 737- 750. -22- Investigation on maturing period of compost from composting toilet # Natsuru YAMAUCHI* , Nowaki HIJIKATA*, Ken USHIJIMA*, Naoyuki FUNAMIZU* * Department of Environmental Engineering, Hokkaido University # [email protected] Keywords: composting toilet: Ammonia nitrogen: germination index Composting toilet, which can decompose human excrete with matrix in the reactor, has been proposed as one solution for sanitation issue in developing country due to advantages for low-cost and promoting vegetable production (Ushijima et al., 2007, Ushijima et al., 2011, Ushijima et al., 2012, Hijikata et al., 2011a). To expand the availability of the toilet in all over the world, several matrixes as an alternative to sawdust is required. It has been suggested that several agricultural wastes (e.g. rice husk and bio-charcoal) were effective for fecal decomposition as the matrix (Hijikata et al., 2011b), on the other hands, information about time required for maturation in each matrixes after setting out from the reactor has been limited, so far. Differed from normal compost such as animal manure or sewer (Tiquia et al., 1996, Zhao et al., 2011), compost from composting toilet is produced by unique operation, since small amount of organic solid such as feces is continuously input in matrix for long time. + Therefore, to know its maturing period for safety plant growth, changes of NH4 −N content and germination index (GI) after composting process were monitored in the present study. Besides, the difference of maturation progress among several matrixes was investgated. Sawdust, rice husk and charcoal (made from rice husk) compost were made as continuous mixing with pig feces (as substitution of human feces) for 53 days. The fecal load ratios of these composts were finally 3.5 (total input feces / total input matrix). All compost samples were left in incuvator at 28°C and 50% humidity supposed tropical semi-arid climate. Compost was sampled at day 0, day 4, day 9, and day 13. All samples were stocked in freezer at -20°C. Germination test was carried out with compost extraction using Komatsuna (Brassica rapa var. peruviridis) (Chikae et al., 2006). In germination test, thirty Komatsuna seeds were set on triplicate filter paper in a petri dish. 8 ml of compost extraction, which was extracted from compost samples with hot water at the ratio of 1: 20 (w:v), was applied in the petri-dish. The petri-dish was wrapped with alminum foil and left in incuvator at 23°C. After 24 h, number of the germinated seeds were counted. After further 96h, root length was recorded. The germination index (GI) was calculated using the following expression; GI(%) = (% seed germination ×% root length) / 100. Zucconi et al. (1981) has proposed 50% of GI as an indicator of phytotoxin-free composts. On the other hands, Tiquia et al. (1996) and Sellami et al. (2008) have used 80% of GI as an indicator of the disappearance of phytotoxicity and maturity of compost. In the present study, therefore, we defined that acceptable compost of GI was 50-80% and best compost of GI was more than 80%. GI values of charcoal compost reached 81% at day 0. The value of rice husk compost reached 52% at day 0. The value of sawdust compost was 35% at day 0 and reached 73% at + day 4 (Figure 1.1). NH4 −N content of charcoal compost day 0, day 4, day 9 day 13 after composting procedure were 2.73 mg/g, 1.26 mg/g, 1.35 mg/g and 1.59 mg/g, respectively. + NH4 −N content of rice husk compost day 0, day 4, day 9 day 13 after composting procedure + were 4.62 mg/g, 4.35 mg/g, 3.62 mg/g and 3.96 mg/g, respectively. NH4 −N content of sawdust compost day 0, day 4, day 9 day 13 after composting procedure were 6.22 mg/g, 4.37 mg/g, 1.27 mg/g and 0.91 mg/g, respectively (Figure 1.2). The conclusions resulting from this study are as follows: (1) Using charcoal for matrix, composting toilet can make best compost without maturation period. (2) Using rice husk for matrix, composting toilet can make acceptable compost without maturation period. (3) Using sawdust for matrix, 4 days maturation period is required to be acceptable compost. -23- GI [%] NH₄⁺‒ N content [mg/g] Figure 1.1 Change of germination index (GI) after composting procedure Days of composting period (Continuous input feces) Figure 1.2 Changes of NH4 −N content of compost + Days of maturation period (No input feces) References Chikae M., Ikeda R., Kerman K., Morita Y. and Tamiya E. (2006) Estimation of maturity of compost from food wastes and agro-residues by multiple regression analysis. Bioresource Technology,97, 1979–1985 Hijikata, N., Yamauchi, N., Ushijima, K. and Funamizu, N. (2011a) Effect of bio-charcoal compost made by composting toilet for Brassica rapa var. peruviridis growth in pot cultivation Proc. 2nd Ameli-Eaur International Workshop on Sustainable Water and Sanitation System & 8th International Symposium on Sustainable Water and Sanitation System Part I, pp.109-114 Hijikata N., Yamauchi N., Yabui K., Ushijima K. and Funamizu N. (2011b) Characterization of several agricultural wastes as a matrix of composting toilet –from fecal degradation to reuse as a soil conditioner-. Proc. 8th IWA International Symposium on Waste Management Problems in AgroIndustries, pp.317-324. Sellami F., Hachicha S., Chtourou M., Medhioub K. and Ammar E. (2008) Maturity assessment of composted olive mill wastes using UV spectra and humification parameters. Bioresource Technology, 99, 6900-6907 Tiquia S.M., Tam N.F.Y. and Hodgkiss I.J. (1996) Effect of composting on phytotoxicity of spent pigmanure sawdust litter. Environmental Pollution, 93, 249-256 Ushijima K., Irie M., Sintawardani N., Triastuti J. and Ishikawa T. (2007) Practical model of sustainable th sanitation system for urban slum in Bandung. Proc. 5 international Symposuim on Sustainable Sanitation, 179-188 Ushijima K., Yabui K., Hijikata N., Ito R., Funamizu N. (2011) Development self-buildable simple composting toilet, Proceedings of IWA aspire (USB-memory), October 2-6, 2011, Tokyo, Japan. Ushijima K., Hijikata N., Ito R. and Funamizu N. (2012) Effect Estimation of Dry-Toilet Application for Rural Farmer Family in Burkina Faso. Journal of Arid Land Studies,22(1), in press Zhao L., Gu W., He P. and Shao L. (2011) Biodegradation potential of bulking agents used in sludge bio-drying and their contribution to bio-generated heat. Water Research,45, 2322-2330 Zucconi F., Forte M., Monaco A., and Bertoldi M. (1981) Biological evaluation of compost maturity. Biocycle,7, 27-29 -24- Anaerobic digestion of food wastes for the production of carbon source for a membrane bioreactor Y. M. Zhang, X. C. Wang*, Y.S.Hu Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi’an University of Architecture and Technology, Xi’an 710055 China *Corresponding author, E-mail: [email protected] Keywords: anaerobic; food wastes; carbon source Abstract: Xi’an Siyuan University is confronted with water shortage because of its location which is on a hill about 13 km far from the centre city, so there is an anaerobic-anoxic-oxic and membrane bioreactor combined process which could supply enough reclaimed water for toilet flushing, gardening, road washing and artificial lake replenishment in all the campus. Now the problem is that the ratio of COD loading (80mg/L~250mg/L) to TN loading(15mg/L~40mg/L)about the campus domestic sewage is not enough for better denitrification effect, which could result in nitrogen accumulation in all the reclaimed water cycle system , also eutrophication may occur in the artificial lake. All of them request us to add new external carbon source to improve ratio of COD to TN , finally reduce nitrogen content in the system. The amount of food wastes in campus dinning hall is more every day. There are a large number of carbohydrate and protein in food wastes which could produce various easy-to-use carbon source for biological nutrients removal. So a good idea comes, that is to use food wastes anaerobic digestion for the production of carbon source for membrane bioreactor. Food wastes in campus dinning hall have some character. The TS(total solid) and VS(volatile solid) have not bigger change every day , TS keeps at 15%~20%, VS keeps at 92~98%, VS/TS generally remain fairly constant. The compositon percentage of carbonaceous organic materials is: carbohydrate (11%~13%), protein (1%~4%), lipid (2%~3%). The concentration of nutrient is: TCOD (200 g/L ~300 g/L), TN (2000 mg/L~4000 mg/L), TP (300 mg/L~450 mg/L). The anaerobic fermentation pot is resin material, whose total volume is 12L and valid volume is 10L. To make the feedstock for experiment, raw food wastes was diluted with tap water and then shredded with a grinder. The mixing of raw food wastes to tap water is 2:1(w:w). Then inoculating right proportion anaerobic sludge, and control the temperature of o reactor at 36 C with water bath, the food wastes anaerobic fermentation begins. We need a short-term fermentation process for practical application, so about 5 days are suitable. Experiment shows that when the fermentation time is 5 days, TS and VS haven’t obvious change; the degradation rate of carbohydrate and protein are respectively 36% and 18%; TCOD and SCOD could increase to a stable status, the ratio of SCOD to TCOD generally grow to about 0.3; total nitrogen concentration has slight rise and total phosphorus concentration have slight dropping; ammonia nitrogen concentration have some rise; the growth rate of latic acid reach to about 4g/L one day; also some volatile fatty acids generate (mainly acetic acid), but the amount is less than latic acid. -25- 10mL 10mL 10mL 100mL Measuring cylinder 100mL Measuring cylinder 100mL Measuring cylinder Magnetic stirrer Magnetic stirrer Magnetic stirrer Figure1 Anaerobic digestion pot and sampling method In future right proportion carbon sources with the form of fermentation liquid are added to membrane bioreactor , under the optimal condition controlling, the total nitrogen in A-A-O and MBR system gets better removal effect. References American Public Health Association, 1985. Standards Methods For the Examination of Water and Wastewater, 16th ed. American Public Health Association, Washington, DC Charles J. banks; Michael Chessire. Anaerobic digestion of source-segregated domestic waste: performance assessment by mass and energy balance. Bioresource Technology. 2011,102,612620 Ruihong zhang; Hamed M.el-mashad. Characterization of food wastes as feedstock for anaerobic digestion. Bioresource Technology 2007, 92, 929-935 -26- Inactivation mechanism of pathogenic bacteria using lime and ash in composting toilet Rui TEZUKA#*, Nowaki HIJIKATA*, Shinobu KAZAMA**,Seyram K. SOSSOU*** Naoyuki FUNAMIZU* * Department of Environmental Engineering, Hokkaido University ** Department of Human Environmental Science, Ochanomizu University *** Department of Teaching and Research in Water Efficiency Management and Sanitation, International Institute for Water and Environmental Engineering #:[email protected] Keywords: composting toilet, high pH condition, inactivation mechanism, pathogenic bacteria A composting toilet, which can aerobically decompose human excreta using agricultural waste as matrix, has been proposed as one solution for sanitary issue in developing country, since the toilet is inexpensive to introduce (Winblad et al., 2004) and can contribute to agricultural production (Hijikata et al., 2011). On the other hands, compost from the toilet requires inactivation treatment against pathogenic microorganisms derived from human feces before agricultural reuse (Sossou et al, 2012). Previous study has shown that high pH conditons was effective for lethal inactivation of pathogenic bacteria and viruses (Kazama et al., 2011). However, information about CaO or wood ash requirement per unit compost and target pH level for inactivation has been still limited.Furthermore, inactivation efficiency and inactivation pattern in alternative composting matrixes such as rice husk and charcoal has not been observed. In the present study, therefore, relatioship between applied CaO or wood ash amount and compost pH was investigated, and then, inactivation rate and damage part of Esherichia coli, regarded as a model of pathogenic bacteria, in several alkaline level of compost were observed with three different media.Moreover on the assumption that CaO is applied when matrix is changec, CaO need was calculated from the viewpoint of risk assessment. Compost of rice husk and charcoal were prepared as continuously input of pig feces for 1 month.Alkarine material used were calcium oxide (CaO), regarding as a calcium lime and commercial wood ash. After adding them to the compost, compost pH was measured after mixing with pure water at the ratio of 1:20 (w:v). Inactivation rate constant of E. coli NBRC3301 in three different pH composts, which were about pH 9.5 (without CaO), 10, and 10.5, was also observed in the present study. Adequate CaO or wood ash and 3 g of autoclaved pig feces were mixed in 50 g of autoclaved charcoal compost, and then 0.3 mL of incuvated E. coli suspension were inoculated in the compost mixture. 0.3 g of the compost mixture was appropriately sampled (0-8 h) and E. coli was extracted with 20 mL of 3% (w/v) beef extract. It was reported that the recoveries of E. coli using this method were 70-100% 4 (Otaki et al., 2002).After adequate dilution (10-10 times), the all extracts were applied in Trptic Soy Agar (TSA), Desooxycholate Agar (DESO) and Compact Dry EC (C-EC), respectively. Then, the media were incuvated at 37°C for one day. Followed by a report of Kazama et al (2011), damage part of E. coli was estimated with inactivation rate constant of each sampling time on each media. Finally infection risk was assessed on the assumption that four member family were infected by salmonella used a composting toilet for 3 mounths. Applied CaO amount and compost pH had liner relation at the range of pH 9-12.To lead the 1 g (dry weight) of compost to pH 10, in the case of charcoal, about 16 mg of CaO was required and in the case of rice husk, 23 mg of CaO was required.Compared to CaO case, wood ash slightly incresed the compost pH and this meant larger amount was requred.In the case of charcoal, 2400 mg of wood ash was required to lead the compost pH to 10.0. Fig. 1 shows the inactivation rate constant in each three media.In the case of charcoal, inactivation rate constants in DESO and C-EC media were relatively higher than that of TSA. This suggested that CaO application caused lethal damage of outer membrane and enzyme activities in E. coli. Because DESO selects outer membrane with lactose medium and C-EC selects b-glucuronidase with pepton, pyruvate and lactose medium. In the case of charcoal, inactivation rate constant in C-EC was higher than those of DESO and TSA. This indicated -27- that enzyme activity tended to get lethal damage. As for the wood ash application, tendecy was similar as the case of CaO. Normarized inactivation rate constant, which was mean value of inactivation rate constant with three media was increased as the pH increases in both matrixes and charcoal was more likely to be affected by alkalization. Compared to CaO case, wood ash was more effecient then CaO at the same pH level.Finally from the viewpoint of risk assessment, it was found that by 900 mg of CaO and reacting for four hours, it will enable to -4 decrease the annual infection risk to 10 in both matrixes. It was concluded that CaO and wood ash application increased the compost pH and promoted inactivation of pathogenic bacteria to induce damages of outer membrane and enzyme activities..At the same pH level, wood ash tended to damaged lethally than CaO but -4 larger amount was requred. Thinking to reduce the infection risk to 10 within 4 hours, about 900 g of CaO was required. Fig 1. Inactivation rate constant in each three media under several pH conditions (charcoal and rice husk) References Hijikata N., Yamauchi N., Yabui K., Ushijima K., Funamizu N. (2011) Characterization of several agricultural wastes as a matrix of composting toilet –from fecal degradation to reuse as a soil conditioner-. Proc. 8th IWA International Symposium on Waste Management Problems in AgroIndustries, 317-324. Kazama S. and Otaki M. (2011) Mechanism for Inactivation of Bacteria and Viruses in Sawdust Used in Composting Toilet. Journal of Water and Environment Technology, Vol. 9, No.1, 53 – 66 Otaki M., Nakagawa N. and Ito Y. (2002) The fate of pathogen in composting toilet and risk assessment. Proc. The 57th Journal of Japan Society and Cicil Engneering Annual conference, Sapporo, Japan, 561-562 Sossou S.K., Ito R., Jibia A., Sou M., Maiga A.H. (2011) Survival od indicator bacteria and helminthes eggs in composting toilet using sawdust as matrix, Proc. 2nd Ameli-Eaur International Workshop on Sustainable Water and Sanitation System & 8th International Symposium on Sustainable Water and Sanitation System Part I, 95-102 Winblad U., Hebert M. S., Calvert P., Morgen P., Rosemarin A., Sawyer R. And Xian J. (2004). Ecological sanitation revised and enlarged edition. Stockholm Environment Institution, Stochholm -28- Design of Resource Recycling Sanitation System Based On Relationship Between Fertilizer Demand And Potential Supply Of Human Excreta As Fertilizer In Indonesia Yosuke Deguchi#*, Ken Ushijima*, Naoyuki Funamizu* *Department of Environmental Engineering, Graduate school of Engineering Hokkaido University, Japan Email: [email protected] Keywords: reuse of human excreta; resource recycling sanitation; Indonesia Improving sanitary condition of highly populated area in Indonesia is urgent task. Wastewater effluent from this area contaminates river and it causes bad sanitary condition. Spread of toilet without treatment facility is cause of this problem. On the other hand, Phosphate are limited resources. Half of phosphate rock will be consumed until 2060’s. We need to recover nutrient including phosphate from human excreta in the near future. Installing composting toilet should become one of the solutions to these problems. Composting toilet can recover nutrient from human excreta as compost. Many kinds of technical approach of composting toilet and compost have been tried untill now. Without consideration of compost usage, composting toilet can not become widespread. Therefore, in this study, we discussed following resource recycling sanitation system (Figure 1). Feces and urine are separately treated by composting toilet. Feces are composted. Urine is stored in plastic tank. Collectors collect compost and urine to collection station. Compost and urine are brought to farmland by handcart and truck, then used for agriculture at farmland. Each stakeholder gets compensation for thier work. When considering driving force of this system, there are three important factors. First point is linkage netwark design, especially material flow. Second point is benefit flow. Giving compensation for people involved sanitation system should be keypoint of their participation to the system. For the above two points, we have to clearify balance of fertilizer demand at farmland and potential supply of fertilizer produced from human excreta by composting toilet. In this study, we estimated current balance between fertilizer demand and potential supply around Bandung city, Indonesia, then drew up fertilizer transportation plan based on case study. Third point is people’s decision making process. In Indonesia, Muslim is the most important major group and Islamic context has big effects on people’s decision making process. Urine and feces are classified “Najis” in Islamic context. Najis is filth and it should be avoided for pray. When we construct resource recycling sanitation system, we have to fit it to Islamic sense. However, there are a lot of undefined matters related to Najis (e.g., Useage of human excreta for agriculture). Therefore, we interviewed three Islamic leaders about Najis and handling of human excreta in resource recycling sanitation system. In Bandung city (Kota BDG) and Cimahi city (Kota Cimahi), fertilizer supply exceeds its demand at farmland. Other areas near Kota BDG , fertilizer supply is less than its demand (Figure 2). Fertilizer demands in Garut, Subang, and Sumedang are 4.0 to 8.6 times higher than supplies. They have big potential to accept fertilizer fromother areas. It is one idea that fertilizer produced in Kota BDG and Cimahi should be transported and consumed to these areas. According to results of interviews to Islamic leaders, cocept and each processes of the sanitation system are basically no problem. Compost produced from human excreta can be used as fertilizer. When people touch compost and human excreta, washing part of body contacted by them is enough to clean people for pray. This interview revealed two considerations. (1) Packing of urine and compost for storage, collection and transportation should be clean. (2) Compensation to people relating to this system is given for their work and fertilizer, not for amount of excreta because paying compensation to Najis is prohibited in Islamic context. -29- Figure 1.1 Basic concept of resource recycling sanitation system Figure 1.2 Fertilizer demand and supply in each area References Ingrid Steen. (1998) Phosphorus availability in the 21st century: Management of a non-renewable resource. Phosphorus and Potassium 17(9/10), 25-31 Ken Ushijima, Mituteru Irie, Neni Sintawardani, Jovita Triastuti and Tadaharu Ishikawa. (2007) Practical th Model of sustainable sanitation system for urban slum in Bandung. Proceedings of the 5 international symposium on sustainable sanitation, 179-188 Ken Ushijima, Mituteru Irie, Neni Sintawardani, Jovita Triastuti and Tadaharu Ishikawa. (2007) Collection system for compost from composting toilet in slum area of Bandung. Environmental engineering research 44, 505-511 Ken Ushijima, Mituteru Irie, Neni Sintawardani, Jovita Triastuti and Tadaharu Ishikawa. (2006) Field research on domestic wastewater from the slums in Bandung city. Annual journal of engineering, JSCE, Vol.50, 1075-1080 -30- Interface design of composting toilet to actual application to rural area of Burkina Faso # Kenta Yabui* , Ken Ushijima*, Ryusei Ito**, Naoyuki Funamizu* * Department of Environmental Engineering, Hokkaido University, Japan **Water, Decontamination, Ecosystem and Health Laboratory, International Institute for Water and Environmental Engineering (2iE), Burkina Faso #[email protected] Keywords: user oriented design, resource recycling sanitation system, composting toilet Resource recycling sanitation system, which utilize composting toilet, is one of the promising concept to improve the sanitary conditions in developing countries. Composting toilet makes it possible for users to reuse human excrement in safe way as fertilizer and users get potential to increase their income by using this fertilizer to vegetable cultivation. It becomes incentive for low income farmers. On the other hand, interface design also gives one of important incentive at actual application. There are few studies on user interface design of composting toilet, though there are many technological studies on composting toilet. In this research, we aimed to design composting toilet that people living in rural area of Burkina Faso willing to choose and use. As a first step, we analyzed design of current toilet and assumed action in it in detail on 6 families which already committed to install and use pilot model. Based on these analyses, we determined each detail of design of composting toilet and toilet room as follows and materialized it. The reactor itself is rotating to mix the compost. In rural area, it is impossible to use electricity to mix the reactor, hence, matrix are mixed by only hand power. We assumed 20 Nm as the maximum of acceptable torque for women and children. Although screw mixing reactor, which is majority of composting toilet, could mix only 12 kg of matrix by 20 Nm, reactor rotating system could mix 34 kg of matrix. The width of aisle and entrance of current toilet were 60 ~ 83 cm and 45 ~ 115 cm, respectively. The size of toilet room was 130 ~ 200 cm long and 130 ~ 180 cm wide. This size is large enough to set composting toilet and to take reactor to outside of toilet room for matrix change. If excess water enters into the reactor, composting reaction will be negatively affected (Narita et al., 2005). Hence, it is better to put the reactor no lower than ground level, to avoid submerging in rain season. In this case, the height of toilet room’s wall becomes higher than current design and extra height also depends on squatting or seating. As far as we asked people in the site, both of squatting and seating seems to be acceptable. The case of seating, height of wall can be 20 cm lower than the case of squatting and it saves construction cost about 5.5 USD. As a prototype, we chose seating style. Several numbers of prototypes are now being installed at pilot families’ house in Burkina Faso. The design will be tested in real conditions and improvement-required point will be abstracted and feed back to improved design. References Hiroki Narita, Miguel Angel Lopez Zavala, Kaori Iwai, Ryusei Ito, Naoyuki Funamizu (2005) Transformation and characterization of dissolved organic matter during the thermophilic aerobic biodegradation of feces. Water Research 39, 4693-4704 -31-
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