Revisiting estimates of municipal solid waste generation per capita and their reliability
- 11k Downloads
Per capita municipal solid waste (MSW) generation, a core indicator of environmental pressure, is a useful measure for evaluating the intensity of waste generation over time and comparing the intensities among cities or countries. We provide an overview of global data on MSW generation per capita at the national and local levels. Although the legal definition of MSW varies from country to country, we conceptualize MSW simply as the waste managed by or for municipalities as a public service. We note the current challenges in estimating MSW generation per capita in developing countries, including a lack of equipment (e.g., weighbridges), lower rates of MSW collection efficiency, and rural–urban migration, all of which may have negative effects on data reliability. Incomplete data compilation systems at the national level also result in lower reliability and reduce the comparability of national data. We suggest technical solutions for estimating MSW generation per capita at the local and national levels to improve reliability and comparability of data.
KeywordsMunicipal solid waste Waste generation Reliability Definition Comparability
Currently, 1.3 billion metric tons of municipal solid waste (MSW) are generated annually in the world, and this amount is expected to rise to about 2.2 billion tons by 2025 , although MSW generation in Organisation for Economic Co-operation and Development (OECD) member countries has been decreasing . MSW generation is influenced by economic conditions, living standards, urbanization [3, 4], and population . Dramatic increases in population in urban areas are typical phenomena in Africa and Asia , and the amount of MSW generated dramatically increases as a consequence. Historical data compilation of MSW generation per capita, a core indicator of environmental pressure [7, 8] to evaluate the intensity of MSW generation, can contribute to better MSW management planning. Data on MSW generation per capita are also useful for comparisons of MSW intensities among countries and cities. In spite of the usefulness of this measure, international comparability is not fully assured because of inconsistent national definitions of MSW and unreliable data on MSW generation per capita. Comprehensive articles reviewing MSW definitions have yet to be published, although some researchers have specifically addressed the definition of MSW in their studies [9, 10, 11, 12].
In this article, we provide an overview of global data on MSW generation per capita at the national and local levels. Because of our concern that the disparity of MSW definitions in the world would lead to reduced comparability, we review various definitions of MSW and accordingly explain about the MSW stream. With a focus on developing countries, we clarify existing local problems with data reliability in terms of MSW generation and the population with MSW collection service because uncertainties seriously affect the reliability and comparability of MSW generation per capita data. We raise the issue of compiling local data for estimation of nationwide MSW generation per capita. We suggest technical solutions for estimating MSW generation per capita at the local and national levels to improve reliability and comparability of data.
Overview of global data on MSW generation per capita
Calculating MSW generation per capita enables data on MSW generation to be normalized and eliminates the effects of changes in population . Per capita data are widely used to compare the intensity of MSW generation among different places [14, 15, 16, 17, 18, 19, 20].
MSW generation per capita at the national level
As an economy matures and environmentally friendly policies are enforced, MSW generation per capita does not always increase in line with economic growth. For example, after 20 years of rapid economic growth through 1997, the government of Taiwan enforced aggressive MSW management practices , which contributed to a large reduction in the per capita MSW generation from 1.14 kg day−1 in 1997 to 0.81 kg day−1 in 2002 , even though the economy continued to grow.
MSW generation per capita at the local level
Tourism may also have an impact on MSW generation [66, 67]. For example, Pattaya (Thailand), a beach resort city approximately 160 km from Bangkok, has a much higher MSW generation per capita (1.00 kg day−1)  than the national average (0.64 kg day−1).
Definitions of MSW
Generally municipalities or local governments have the responsibility of managing MSW, with a few exceptions such as in Malaysia, which shifted the responsibility for MSW to the federal government . The existence of different definitions of MSW  makes it confusing to interpret and compare estimates of MSW generation in various countries.
Waste is generated in all sorts of ways and its composition and volume largely depend on consumption patterns and on industrial and economic structures . Although the legal definition of waste differs among countries, wastes are substances or objects that are disposed of, intended to be disposed of, or required to be disposed of by the provisions of national law according to Article 2 of the Basel Convention on the control of transboundary movements of hazardous wastes and their disposal. Waste is similarly defined in EU Directive 2008/98/EC as any substance or object that the holder discards, intends to discard, or is required to discard . In another sense, waste refers to material that is discarded without being resold to other persons or companies, and it generates collection, transportation, and disposal costs. In Japan, after careful and comprehensive evaluations, waste is defined on the basis of the following five categories—(a) item meets required quality for use, (b) supply and demand, (c) product market, (d) transaction value, and (e) intention of owner to sell. Under this type of definition, recyclables (salables) are not considered to be waste.
In general, the sources (generators) of and the properties of waste defined as MSW determine the application range of MSW , but Buenrostro et al.  conceptualized the territorial limits of a municipality as the boundary of MSW. According to the OECD , “Municipal waste is waste collected by or on behalf of municipalities. It includes household waste originating from households (i.e. waste generated by the domestic activity of households) and similar waste from small commercial activities, office buildings, institutions such as schools and government buildings, and small businesses that treat or dispose of waste at the same facilities used for municipally collected waste.” However, the definition reported by the World Bank includes industrial waste and construction and demolition waste in MSW streams . Rodic et al.  reported that several municipalities such as Adelaide in Australia and Belo Horizonte in Brazil also include construction and demolition waste as MSW. The Canadian government also defines construction and demolition waste as a component of MSW . The US Environmental Protection Agency definition does not include construction and demolition debris, biosolids (sewage sludges), industrial process wastes, junked cars and trucks, or combustion ash, but US states have different definitions of MSW .
For the purposes of national annual reporting of MSW from EU countries, the Eurostat/OECD defines MSW to include household and similar wastes, placing emphasis on inclusion by listing all the possible sources and material types . Another EU commission decision defines municipal waste to include household and similar wastes, but to exclude production waste and waste from agriculture and forestry . Chapter 20 in the European List of Wastes defines municipal waste as household waste and similar commercial, industrial, and institutional wastes, including street cleaning residues, septic tank sludge, and waste from sewage cleaning . Most EU member countries use this List of Wastes as a guide when compiling statistics, even though they are not obligated to do so . The List of Wastes excludes packaging waste from municipal waste to emphasize producer responsibility for packaging waste, and this exclusion may cause EU member countries to have different definitions of MSW. For example, packaging waste destined for recycling is included as MSW in the United Kingdom  and Denmark , but it is not always reported as MSW in Germany  and France . The variance is a result of different policies on producer responsibility among EU member countries.
The definitions also vary across Southeast Asia. The Philippine definition of municipal waste as defined by Republic Act No. 9003 refers to wastes produced from activities within local governmental units, including domestic, commercial, institutional, and industrial wastes as well as street litter. Malaysia, Vietnam, and Cambodia, on the other hand, have no legal definition of MSW . Waste managed by or for municipalities is often translated as MSW in English regardless of the official wording in the native language. Countries without a legal definition of MSW in relevant laws do not use the terms “municipal solid waste” or “MSW” in their native languages, and the waste categories can often be translated into English as “ordinary solid waste,” “urban solid waste,” or similar terms. In an exact translation, the Japanese government considers the MSW category as “general waste,” and general waste is defined simply as waste other than industrial waste, all of which shall be managed by or for municipalities according to the Waste Management and Public Cleansing Act.
Waste can be categorized as hazardous or non-hazardous. Non-hazardous wastes generated from relatively small-scale sources and public spaces tend to be thought of as MSW. Non-hazardous wastes consist of kitchen waste, garden waste, paper and cardboard, textiles, plastics, metals, and similar materials  that are generated from the activities of daily life. Electrical and electronic waste (e-waste), batteries, fluorescent lamps, and spray cans disposed of by households are also usually regarded as MSW, even though they may contain hazardous materials [84, 85]. Infectious wastes such as needles and blood generated from hospitals and clinics are designated as specially controlled wastes and are not included as MSW in Japan . However, bandages and surgical cotton containing blood generated from the same types of places are managed as MSW. Waste materials originating from home health and medical care services are included in MSW .
Globally, it appears that household waste is the main component of MSW, even though it may contain some amount of hazardous materials. Other than household waste, each municipality determines the sources and types of waste to be covered by MSW management depending on political, historical, social, and economic factors. Some municipalities may also regard waste from industry as MSW. MSW can be simply conceptualized as the waste managed by or for municipalities as a public service through a public works budget. MSW is often managed by private companies on behalf of local governments through private finance initiatives and public private partnerships [88, 89]. When calculating MSW generation per capita, the reporters of the data should clearly note and declare the sources and types of waste included as MSW to verify the comparability of data.
Identification of the MSW stream from the source of waste generation
The MSW stream excludes other two streams. The first is recyclables collected by anyone other than municipalities, such as the private sector and the informal sector (Fig. 11c). This stream emerges in isolation from MSW and is mainly driven by economic incentives. This type of recycling is often observed in developing countries [90, 91, 92], where junk buyers in cities and waste pickers at dumping sites recover recyclables to earn a living [93, 94]. The informal sector accordingly contributes to a reduction of MSW generation and drives the recycling process in developing countries . Communities and schools can also be key actors for recycling. In Thailand, waste banks in the community and at schools play an important role as places where pupils and residents can sell recyclable materials . Wong Panit, a Thai private trading company of recyclables, initially partnered with the city of Phitsanulok in Thailand to set up waste banks and promote community-based recycling activities, resulting in a drastic decrease in the amount of MSW generated  and reaching the activities to reduce MSW in Bangkok .
The other waste stream excluded is that which is self-disposed of at the source (Fig. 11d). This type of waste stream is commonly seen in regions where MSW collection service is unavailable . Burning, composting, burial, and disposal into water bodies are examples of self-disposal regardless of whether they are done properly or improperly . Composting at the household level in Surabaya, Indonesia , is a good example of appropriate self-disposal.
Data on the amount of MSW disposal do not necessarily correspond to those of MSW generation, especially in developing countries . Many municipalities throughout the world tend to report the amount of MSW disposed of as well as that recycled as the amount of MSW generated because the data are recorded at disposal and recycling sites equipped with weighbridges. In fact, some of the recyclables are informally recovered from the MSW stream (Fig. 11a) and flow into recyclable stream (Fig. 11c) during each process in developing countries—by waste pickers during the discharge process, by MSW collection workers during the collection process, by MSW transportation workers during the transportation process, and by waste pickers during the disposal process [101, 102].
Reliability of data related to MSW generation per capita
Municipal solid waste generation per capita is simply calculated as the amount of MSW generated divided by the population with MSW collection service. Uncertainty in either value can negatively affect the reliability and comparability of the data. Here the potential causes of the uncertainties, especially in developing countries, are discussed and feasible solutions to improve the uncertainties are suggested. Non-MSW waste streams are not accounted for and the amount of MSW disposal is considered to be equal to that of MSW generation in the following discussion, even though that may not necessarily be the case in developing countries.
Amount of MSW generation at the local level
Limited MSW collection service at the local level
Statistical demographics should not be used to calculate MSW generation per capita; rather, population with MSW collection service should be used. Data on population with MSW collection service may be uncertain in developing countries because of issues related to collection efficiency and rural–urban migration. These issues can result in both underestimations and overestimations of MSW generation per capita.
The increase in population in urban areas in developing countries is often caused by domestic as well as transboundary rural–urban migration [109, 110] rather than by natural population growth. About 42.5 % of Kolkata’s (India) 8 million residents are transient , and every major city in developing countries may have similarly large proportions of unregistered migrants. Migrants often start living in populated cities as slum dwellers, and few register their residency in the destination city . A lack of basic services such as waste collection, electricity, and water supply is one of the most frequently mentioned characteristics of slums . Waste generated in slums tends to be improperly burned or dumped into nearby streets and rivers, but a large proportion of the waste inappropriately disposed of is eventually collected and managed by or for municipalities as a matter of public health. Not including the transient population in slums can lead to overestimations of MSW generation per capita in these areas.
Data compilation system at the national level
With enough data, the values of nationwide MSW generation per capita estimated by Eqs. (4) and (5) would approximate each other; for example, MSW generation per capita in Japan estimated by Eqs. (4) and (5) were 0.9006 and 0.9032 kg, respectively, based on data from FY2012 compiled from all municipalities (n = 1715). However, if fewer data on MSW generation per capita can be collected from municipalities, the reliability of average data estimated by Eq. (5) will be reduced, and the estimates will not necessarily be close to those generated by Eq. (4). National governments should compile data on MSW generation and population with MSW collection service from as many municipalities as possible in developing countries to improve the reliability of data on MSW generation per capita.
One reason that data on MSW management are not exhaustively compiled in developing countries is that local governments do not have financially close connections with national governments. Conversely, the Japanese government established a data compilation system. The Ministry of the Environment, which holds jurisdiction over waste management in Japan, requires all municipalities to report data on local MSW management, including MSW generation and population with MSW collection service, annually to collect basic information to improve MSW management in Japan. From a practical standpoint, the municipalities are motivated to collect reliable data on local MSW management and prepare detailed plans for constructing new waste treatment facilities because it is a condition of receiving a subsidy from the Ministry of the Environment.
A lack of education and training of local staff in developing countries may lead to misreporting of local MSW data to national governments. Municipal staff may carelessly or erroneously handle data on MSW generation and population with MSW collection service . The national governments should, therefore, verify the data from municipalities. Estimating MSW generation per capita by dividing the amount of MSW generation by the population with MSW collection service is a simple but effective way to identify obvious errors in the reported data . About 50 % of the 157 countries shown in Figs. 1, 2, 3, 4, 5, 6, 7 had a MSW generation per capita of 0.53–1.39 kg, so values very far outside of that range should be reevaluated. For example, MSW generation per capita values of 0.10 or 10 kg should be considered suspect because simple calculation or data entry errors may have occurred in estimating the values.
Differences in the amount of MSW generated per capita should reflect each nation’s or municipal area’s different state of socio-economic growth and the nature of environmental policies. Other factors, however, also contribute to poor comparability among different areas. These include differences in the definition of MSW and uncertainties in the data used to calculate MSW generation per capita. The definition of MSW also varies from country to country because each country and municipality define MSW based on its own political, social, and economic framework. That said MSW can be simply conceptualized as the waste managed by or for municipalities as a public service. A lack of equipment (e.g., weighbridges), lower rates of MSW collection efficiency, rural–urban migration, and incomplete data compilation systems at the national level all affect the reliability of data used to estimate MSW generation per capita in developing countries. Although uncertainties can never be completely eliminated, data on population with MSW collection service as well as MSW generation should be estimated as accurately as possible. Otherwise, local and national governments will estimate MSW generation per capita improperly, which hampers the comparability of estimates both over time and among regions.
- 1.Hoornweg D, Bhada-Tata P (2012) What a waste: a global review of solid waste management. World Bank, Washington, DCGoogle Scholar
- 2.OECD (2013) Municipal waste. Environment at a Glance 2013: OECD Indicators. OECD PublishingGoogle Scholar
- 6.United Nations (undated) Urban and rural areas 2009. http://www.un.org/en/development/desa/population/publications/urbanization/urban-rural.shtml. Accessed 1 Dec 2014
- 7.OECD (2003) OECD environmental indicators: development, measurement and use. Reference paper. OECDGoogle Scholar
- 8.OECD (2008) OECD key environmental indicators 2008. OECDGoogle Scholar
- 12.Rodic L, Scheinberg A, Wilson DC (2010) Comparing solid waste management in the world’s cities. Key-note paper at ISWA World Congress 2010, Hamburg. http://www.iswa.org/uploads/tx_iswaknowledgebase/Rodic.pdf. Accessed 1 Dec 2014
- 13.European Environment Agency (2013) Managing municipal solid waste—a review of achievements in 32 European countries. European Environment Agency, Copenhagen. http://www.eea.europa.eu/publications/managing-municipal-solid-waste. Accessed 1 Dec 2014
- 18.OECD (2013) Municipal waste. Environment at a Glance 2013: OECD Indicators. OECDGoogle Scholar
- 21.OECD (undated) Municipal waste, Generation and Treatment. Complete databases available via OECD’s iLibrary. http://stats.oecd.org/Index.aspx?DataSetCode=MUNW. Accessed 1 Dec 2014
- 22.Ministry of the Environment of Japan (undated) Ippan haikibutsu shori jittai chousa kekka (Results of survey on current municipal solid waste management) (in Japanese)Google Scholar
- 23.United States Environmental Protection Agency (2014) Municipal solid waste generation, recycling, and disposal in the United States: Facts and figures for 2012. United States Environmental Protection Agency, Washington, DCGoogle Scholar
- 24.Conference Board of Canada (undated) Municipal Waste Generation. http://www.conferenceboard.ca/hcp/details/environment/municipal-waste-generation.aspx. Accessed 1 Dec 2014
- 25.AIT/UNEP RRC.AP (2010) Municipal waste management report: Status-quo and issues in Southeast and East Asian countries. http://www.environment-health.asia/userfiles/file/Municipal%20Waste%20Report.pdf. Accessed 1 Dec 2014
- 26.Thein UM (2010) GHG emissions from waste sector of INC of Myanmar. The 8th Workshop on GHG inventories in Asia (WGIA8). VientianeGoogle Scholar
- 27.Asian Development Bank (2013) Solid waste management in Nepal: current status and policy recommendations. Asian Development Bank, MandaluyongGoogle Scholar
- 28.Annepu RK (2012) Sustainable solid waste management in India. Columbia University, New York. http://www.seas.columbia.edu/earth/wtert/sofos/Sustainable%20Solid%20Waste%20Management%20in%20India_Final.pdf. Accessed 1 Dec 2014
- 29.Enayetullah I, Sinha AHMM, Khan SSA (2005) Urban solid waste management scenario of Bangladesh: problems and prospects. Waste Concern Technical Documentation. http://www.wasteconcern.org/Publication/Waste%20Survey_05.pdf. Accessed 1 Dec 2014
- 32.World Bank (1999) What a waste: solid waste management in Asia. http://web.mit.edu/urbanupgrading/urbanenvironment/resources/references/pdfs/WhatAWasteAsia.pdf. Accessed 1 Dec 2014
- 33.Peterson C (2013) Assessment of solid waste management practices and its vulnerability to climate risks in Maldives Tourism Sector. http://tourism.gov.mv/downloads/tap/2014/Solid_Waste.pdf. Accessed 1 Dec 2014
- 35.United Nations Statistics Division (undated) Environmental indicators: waste. http://unstats.un.org/unsd/environment/municipalwaste.htm. Accessed 1 Dec 2014
- 37.Eurostat (undated) Municipal waste statistics. http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Municipal_waste_statistics. Accessed 1 Dec 2014
- 38.Tello Espinoza P, Martínez Arce E, Daza D, Soulier Faure M, Terraza H (2010) Regional evaluation on urban solid waste management in Latin America and the Caribbean: 2010 report. UN-HABITATGoogle Scholar
- 39.Planning Institute of Jamaica (2007) Management of hazardous and solid wastes in Jamaica. http://pioj.gov.jm/portals/0/sustainable_development/management_of_wastes.pdf. Accessed 1 Dec 2014
- 40.Basel Convention, Zoï Environment Network, GRID-Arendal (2012) Biogas and compost. Vital Waste Graphic 3. Basel Convention, BelleyGoogle Scholar
- 41.Stucki S, Wochele J, Ludwig C, Brandl H, Youcai Z (2003) Waste disposal: what are the impacts? Municipal solid waste management: strategies and technologies for sustainable solutions. Springer, BerlinGoogle Scholar
- 42.Khatib IA (2011) Municipal solid waste management in developing countries: future challenges and possible opportunities. Integrated waste management, vol II. InTech, ShanghaiGoogle Scholar
- 44.UNDP (2013) Technical notes. Human Development Report 2013. http://hdr.undp.org/sites/default/files/hdr_2013_en_technotes.pdf. Accessed 1 Dec 2014
- 45.World Bank (undated) GDP per capita. http://data.worldbank.org/indicator/NY.GDP.PCAP.CD. Accessed 1 Dec 2014
- 46.World Bank (undated) GNI per capita, Atlas method. http://data.worldbank.org/indicator/NY.GNP.PCAP.CD. Accessed 1 Dec 2014
- 47.UNDP (undated) Human Development Index. http://hdr.undp.org/en/statistics/hdi. Accessed 1 Dec 2014
- 51.Japan International Cooperation Agency, Pacific Consultants International, Yachiyo Engineering Co., Ltd (2005) The study on the solid waste management in Dhaka City: final report. Japan International Cooperation Agency, TokyoGoogle Scholar
- 54.Jakarta Provincial Government (2012) Solid waste handling management: a case of Jakarta. Review and Planning Workshop on Eco-town, PenangGoogle Scholar
- 55.Annepu RK (2012) Sustainable solid waste management in India. Columbia University, United StatesGoogle Scholar
- 63.Kawai K, Osako M (2011) Estimation of recyclable waste flows in Hanoi, Vietnam (in Japanese). Environ Sanit Eng Res 25:21–29Google Scholar
- 65.World Bank, Ministry of Natural Resources and Environment and Waste-Econ Project (2004) Vietnam environment monitor 2004. World Bank, HanoiGoogle Scholar
- 69.UNEP, CalRecovery Inc. (2005) Solid waste management. UNEPGoogle Scholar
- 70.UNEP, Secretariat of the basel convention on the control of transboundary movements of hazardous wastes and their disposal (2004) Vital waste graphics. UNEPGoogle Scholar
- 71.EU (2008) Directive 2008/98/EC of the European Parliament and of the Council of 19 November 2008 on waste and repealing certain Directives. http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32008L0098. Accessed 1 Dec 2014
- 75.Eurostat (2012) Guidance on municipal waste data collection. EurostatGoogle Scholar
- 76.EU (2011) Commission Decision of 18 November 2011 establishing rules and calculation methods for verifying compliance with the targets set in Article 11(2) of Directive 2008/98/EC of the European Parliament and of the Council (notified under document C(2011) 8165) (2011/753/EU). http://eur-lex.europa.eu/legal-content/EN/TXT/?qid=1404206037534&uri=CELEX:32011D0753. Accessed 1 Dec 2014
- 77.EU (2000) Commission decision of 3 May 2000 replacing Decision 94/3/EC establishing a list of wastes pursuant to Article 1(a) of Council Directive 75/442/EEC on waste and Council Decision 94/904/EC establishing a list of hazardous waste pursuant to Article 1(4) of Council Directive 91/689/EEC on hazardous waste (notified under document number C (2000) 1147) (2000/532/EC). http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CONSLEG:2000D0532:20020101:EN:PDF. Accessed 1 Dec 2014
- 78.Communities European (2005) Waste generated and treated in Europe. Office of Official Publications of the European Communities, LuxembourgGoogle Scholar
- 79.Watson D (2013) Municipal waste management in the United Kingdom. European Environment Agency. http://www.eea.europa.eu/publications/managing-municipal-solid-waste/united-kingdom-municipal-waste-management. Accessed 1 Dec 2014
- 80.Kjær B (2013) Municipal waste management in the Denmark. European Environment Agency. http://www.eea.europa.eu/publications/managing-municipal-solid-waste/denmark-municipal-waste-management. Accessed 1 Dec 2014
- 81.Fischer C (2013) Municipal waste management in Germany. European Environment Agency. http://www.eea.europa.eu/publications/managing-municipal-solid-waste/germany-municipal-waste-management. Accessed 1 Dec 2014
- 82.Gentil EC (2013) Municipal waste management in France. European Environment Agency. http://www.eea.europa.eu/publications/managing-municipal-solid-waste/france-municipal-waste-management. Accessed 1 Dec 2014
- 83.Inter-Organization Programme for the Sound Management of Chemicals (2013) Guidelines for national waste management strategies. UNEP. http://www.unep.org/ietc/Portals/136/Publications/Waste%20Management/UNEP%20NWMS%20English.pdf. Accessed 1 Dec 2014
- 97.Velis CA, Wilson DC, Rocca O, Smith SR, Mavropoulos A, Cheeseman CR (2012) An analytical framework and tool (‘InteRa’) for integrating the informal recycling sector in waste and resource management systems in developing countries. Waste Manag Res 30:43–66. doi: 10.1177/0734242X12454934 CrossRefGoogle Scholar
- 99.Kurniawan TA, Oliveira JPD, Premakumara DGJ, Nagaishi M (2013) City-to-city level cooperation for generating urban co-benefits: the case of technological cooperation in the waste sector between Surabaya (Indonesia) and Kitakyushu (Japan). J Clean Prod 58:43–50. doi: 10.1016/j.jclepro.2013.08.002 CrossRefGoogle Scholar
- 103.Kawai K, Huong LTM, Osako M (2012) Accumulation and reliability of data on municipal solid waste management in urban areas of Vietnam. J Jpn Soc Civil Eng Ser G (Environ Res) 68:II_465–II_471Google Scholar
- 104.UN-HABITAT (2010) State of the world’s cities 2010/2011—cities for all: bridging the urban divide. UN-HABITAT, LondonGoogle Scholar
- 106.Department of Environmental Affairs of Republic of South Africa (undated) General waste. State of the environment. http://soer.deat.gov.za/369.html. Accessed 1 Dec 2014
- 112.General Statistics Office of Vietnam, United Nations Population Fund (2006) The 2004 Vietnam migration survey: the quality of life of migrants in Vietnam. Statistical Publishing House, HanoiGoogle Scholar
- 113.UN-HABITAT (2003) The Challenge of Slums - Global Report on Human Settlements 2003. UN-HABITAT, LondonGoogle Scholar
- 114.Kawai K, Huong LTM, Osako M (2012) Progress on collection amount of municipal solid waste in Hanoi, Vietnam (in Japanese). Environ Sanit Eng Res 26:108–111Google Scholar
- 115.Kawai K (2014) Reliable data collection and compilation of municipal solid waste generation: Challenges and possible improvements at local level in developing countries. 1st 3R International Scientific Conference on Material Cycles and Waste Management. KyotoGoogle Scholar
Open AccessThis article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.