Social vulnerabilities of female waste pickers in Brasília, Brazil.

Worldwide, waste pickers are exposed to adverse health effects resulting from hazards at work. This study aimed to identify possible gender disparities among waste pickers. A quantitative cross-sectional epidemiological study, using semi-structured data was conducted in Estrutural's dumpsite, Brasília, Brazil. It included 1,025 waste pickers, with 67% being female. Most of them lived without partners (73.7%), have 3 to 4 children (47.8%), and have a lower monthly income (62.6%

Conhecimento e comportamento autorreferidos sobre descarte domiciliar de medicamentos / Authorreferated knowledge and behavior on disposal of domiciliary medicines / Conocimiento y comportamiento autorreferidos sobre descarte domiciliar de medicamentos

Objetivo: Analisar o conhecimento e comportamento autorreferidos sobre o descarte domiciliar de medicamentos. Método: Estudo transversal tipo survey, com dados coletados por meio de um questionário em maio de 2017, na cidade de Picos­PI, com amostra de 153 residências. Resultados: Sobre o conhecimento autorreferido, apesar de 139 (90,8%) afirmarem ter ciência sobre o risco ambiental, 144 (94,1%) relataram não ter conhecimento sobre local adequado de realizar o descarte,104 (68,0%) admitiram que o modo como descarta os medicamentos no ambiente traz algum risco individual e 118 (77,1%) perceberam a existência de risco coletivo. Quanto ao comportamento, 107 (69,9%) afirmaram já ter descartado medicamento devido ao fato do prazo de validade vencido, e a maioria afirmou realizar o descarte dentro da embalagem original e no lixo doméstico, 124 (81,0%). Conclusão: O conhecimento e comportamento autorreferidos demonstram fragilidades que comprometem a saúde pública e ambiental

Objective: To analyze the self-reported knowledge and behavior on the disposal of medicines. Method: A cross-sectional study with data collected through a questionnaire in May 2017, in the city of Picos-PI, with a sample of 153 residences. Results: Regarding the selfreported knowledge, 139 (90.8%) stated that they had knowledge about environmental risk, 144 (94.1%) reported having no knowledge of the appropriate disposal site. 104 (68.0%) admit that the way they dispose of medicines in the environment poses some individual risk and 118 (77.1%) perceive the existence of a collective risk. Regarding the behavior, 107 (69.9%) stated that they had discarded medication due to the fact that the expiration date had expired, and the majority stated that they disposed of 124 (81.0%) in the original packaging and household waste. Conclusion: Self-reported knowledge and behavior demonstrate fragilities that compromise public and environmental health

Objetivo: Analizar el conocimiento y el comportamiento autorreferidos sobre el descarte domiciliar de medicamentos. Método: Estudio transversal tipo survey, con datos recogidos por medio de un cuestionario en mayo de 2017, en la ciudad de Picos-PI, con muestra de 153 residencias. Resultados: Sobre el conocimiento autorreferido a pesar de 139 (90,8%) afirmar tener ciencia sobre el riesgo ambiental, 144 (94,1%) relató no tener conocimiento sobre el lugar adecuado de realizar el descarte. (68,0%) admite que el modo en que descarta los medicamentos en el ambiente trae algún riesgo individual y 118 (77,1%) percibe la existencia de riesgo colectivo. En cuanto al comportamiento, 107 (69,9%) afirmaron ya haber descartado medicamento debido al hecho del plazo de validez vencido, y la mayoría afirmó realizar el descarte dentro del embalaje original y en la basura doméstica, 124 (81,0%). Conclusión: El conocimiento y comportamiento autorreferidos demuestran fragilidades que comprometen la salud pública y ambiental

Elevated Blood Lead Levels in Infants and Children in Haiti, 2015.

OBJECTIVE: Few studies have reported blood lead levels (BLLs) in Haitian children, despite the known presence of lead from environmental factors such as soil, water, leaded paint and gasoline, improperly discarded batteries, and earthquakes. We sought to determine the prevalence of elevated blood lead levels (EBLLs) among healthy Haitian children. METHODS: We enrolled children aged 9 months to 6 years from 3 geographic areas in Haiti (coastal, urban, and mountain) from March 1 through June 30, 2015. We obtained anthropometric measurements, household income, potential sources of lead exposure, and fingerstick BLLs from 273 children at 6 churches in Haiti. We considered a BLL ≥5 µg/dL to be elevated. RESULTS: Of 273 children enrolled in the study, 95 were from the coastal area, 78 from the urban area, and 100 from the mountain area. The median BLL was 5.8 µg/dL, with higher levels in the mountain area than in the other areas ( P < .001). BLLs were elevated in 180 (65.9%) children. The prevalence of EBLL was significantly higher in the mountain area (82 of 100, 82.0%; P < .001) than in the urban area (42 of 78, 53.8%) and the coastal area (56 of 95, 58.9%; P < .001). Twenty-eight (10.3%) children had EBLLs ≥10 µg/dL and 3 (1.1%) children had EBLLs ≥20 µg/dL. Exposure to improperly discarded batteries ( P = .006) and living in the mountain area ( P < .001) were significant risk factors for EBLLs. CONCLUSIONS: More than half of Haitian children in our study had EBLLs. Public health interventions are warranted to protect children in Haiti against lead poisoning.

A systematic approach to evaluate parameter consistency in the inlet stream of source separated biowaste composting facilities: A case study in Colombia.

Biowaste is commonly the largest fraction of municipal solid waste (MSW) in developing countries. Although composting is an effective method to treat source separated biowaste (SSB), there are certain limitations in terms of operation, partly due to insufficient control to the variability of SSB quality, which affects process kinetics and product quality. This study assesses the variability of the SSB physicochemical quality in a composting facility located in a small town of Colombia, in which SSB collection was performed twice a week. Likewise, the influence of the SSB physicochemical variability on the variability of compost parameters was assessed. Parametric and non-parametric tests (i.e. Student's t-test and the Mann-Whitney test) showed no significant differences in the quality parameters of SSB among collection days, and therefore, it was unnecessary to establish specific operation and maintenance regulations for each collection day. Significant variability was found in eight of the twelve quality parameters analyzed in the inlet stream, with corresponding coefficients of variation (CV) higher than 23%. The CVs for the eight parameters analyzed in the final compost (i.e. pH, moisture, total organic carbon, total nitrogen, C/N ratio, total phosphorus, total potassium and ash) ranged from 9.6% to 49.4%, with significant variations in five of those parameters (CV>20%). The above indicate that variability in the inlet stream can affect the variability of the end-product. Results suggest the need to consider variability of the inlet stream in the performance of composting facilities to achieve a compost of consistent quality.

Household waste and health risks affecting waste pickers and the environment in low- and middle-income countries.

Household waste has evolved into a core urban challenge, with increased quantities of waste being generated and with more complex material compositions, often containing toxic and hazardous elements. Critical systems theory understands cities as urban metabolisms, with different material and energy flows, highlighting the circularity in production, consumption, and discard. Waste pickers in low- and medium-income countries work on dumps and landfills, sifting through highly contaminated household waste and are exposed to health hazards. This paper discusses the risk factors, hazards, and vulnerabilities waste pickers are exposed to during collection and separation of recyclables, based on the review of literature on waste and environmental health and on findings from participatory research with waste pickers conducted in Brazil. We take a social and environmental justice perspective and identify the vulnerabilities and waste-borne hazards of household waste, associated with these workers, their communities, watersheds, and the environment. Household waste, although not always per se toxic or hazardous, can become a hazard if not collected or inadequately managed. Those communities where household waste is not collected or waste collection is insufficient are the most critical places. Informal and organized waste pickers, municipal or private waste collectors/workers, small waste traders and sometimes residents, particularly small children, may be considered vulnerable if exposed to waste-borne hazards. The results include recommendations to address household waste-borne hazards and vulnerabilities, according to waste workers involved in this research.

[Environmental conditions and prevalence of parasitic infection in Xukuru-Kariri indigenous people, Caldas, Brazil]. / Condições ambientais e prevalência de infecção parasitária em indígenas Xukuru-Kariri, Caldas, Brasil.

OBJECTIVE: To describe the environmental conditions and the parasitic infection status of Xukuru-Kariri individuals living in the municipality of Caldas, state of Minas Gerais, Brazil. METHODS: A cross-sectional study was carried out in March 2009. Sociodemographic and environmental data were collected through interviews. Water and fecal samples were collected for determination of environmental contamination and parasitic infection status. RESULTS: The Xukuru-Kariri population living in Caldas included 86 people divided into 22 families. Of 22 heads of household, 81.8% had low schooling (not higher than elementary education). Of 26 water samples collected for microbiological analysis, 77.0% were positive for total coliforms and 4.0% for Escherichia coli. Residents of 27.3% of households defecated in the open. Trash was scattered in the yard of 54.5% of households. Fecal samples were collected from 60 individuals, with parasitic infection in 66.6%. The following prevalence rates were recorded: Entamoeba histolytica/dispar, 6.7%; Entamoeba coli, 60.0%; Endolimax nana, 1.8%; and Giardia duodenalis, 6.6%. CONCLUSIONS: The people included in this study faced environmental characteristics that contributed to their health vulnerability. Health actions as well as the implementation of public policies to provide sanitation, with quality water and adequate collection and treatment of human and household waste, are essential to prevent environmental degradation and improve the quality of life of these individuals.

Individual and contextual factors related to dental caries in underprivileged Brazilian adolescents.

BACKGROUND: Investigate the individual and contextual variables related to caries in underprivileged adolescents, and the disparity in distribution of the disease. METHODS: Cross-sectional analytical study, conducted in the city of Piracicaba, SP, Brazil, in 2012. The probabilistic sample was composed of 1,179 adolescents from 15-19 years of age, randomly selected from 21 state schools and 34 Primary Health Units--Family Health (PHU-FH). The dependent variables studied were number of decayed teeth and caries experience (DMFT). The independent variables were classified into individual (clinical, sociodemographic, psychosocial, self-perception, impact on oral health, access to services, and quality of life) and contextual (social exclusion index, total number of residents in suburb, literacy rate, and the following variables given in percentages: residences in the home ownership category, provision of domestic sewerage, trash collection, families with income of over 1 minimum wage per month, and families without monthly income) variables. The multilevel regression model was estimated by the PROC GLIMMIX (Generalized Linear Models-Mixed) procedure, considering the individual variables as Level 1 and the contextual variables of the suburbs as Level 2. Adjustment of the model was evaluated by -2 Res Log Likelihood with α = 0.05. RESULTS: As regards the individual variables, adolescents who declared having a prison inmate in the Family and resided in homes with a larger number of persons, showed a higher number of decayed teeth. There were a larger number of decayed teeth, a higher DMFT value, and worse self-perception as regards the health of their teeth and mouth. Other variables, such as being of the female gender, age and time since last visit to the dentist were related to the DMFT index. As regards the contextual variables, the DMFT was lower in suburbs with greater access to domestic sewage, and the number of decayed teeth was higher in suburbs with the worst social exclusion indices. CONCLUSION: Individual and contextual variables were associated with the presence of caries and DMFT index in underprivileged adolescents, indicating that they must be taken into consideration in the formulation of policies directed towards oral health promotion and prevention activities in this group.

Seasonal analysis of the generation and composition of solid waste: potential use--a case study.

Ensenada health officials lack pertinent information on the sustainable management of solid waste, as do health officials from other developing countries. The aims of this research are: (a) to quantify and analyze the household solid wastes generated in the city of Ensenada, Mexico, and (b) to project biogas production and estimate generation of electrical energy. The characterization study was conducted by socioeconomic stratification in two seasonal periods, and the biogas and electrical energy projections were performed using the version 2.0 Mexico Biogas Model. Per capita solid waste generation was 0.779 ± 0.019 kg per person per day within a 98 % confidence interval. Waste composition is composed mainly of food scraps at 36.25 %, followed by paper and cardboard at 21.85 %, plastic at 12.30 %, disposable diapers at 6.26 %, and textiles at 6.28 %. The maximum capacity for power generation is projected to be 1.90 MW in 2019. Waste generated could be used as an intermediate in different processes such as recycling (41.04 %) and energy recovery (46.63 %). The electrical energy that could be obtained using the biogas generated at the Ensenada sanitary landfill would provide roughly 60 % of the energy needed for street lighting.

[Solid healthcare waste: a snapshot of the commitment of the nursing staff]. / Resíduos sólidos de serviços de saúde: uma fotografia do comprometimento da equipe de enfermagem.

This work investigated knowledges and attitudes of nurses from the staff of Hospital de Clínicas de Porto Alegre (HCPA), Rio Grande do Sul, Brazil, on solid healthcare waste (SHCW). This is an exploratory descriptive research with a qualitative approach. The data were obtained from semi-structured interviews applied to 24 nurses from the staff. Content analysis was used to categorize the data. Four categories were identified: Meaning of the phrase solid healthcare waste; Separation of solid healthcare waste; Realization of the course/knowledge; and Professionals who do not separate. Results confirmed the importance to treat this issue more seriously, emphasizing the need of access to appropriate guidance.

Resíduos sólidos de serviços de saúde: uma fotografia do comprometimento da equipe de enfermagem / Residuos sólidos de servicios de salud: una fotografía del comprometimiento del equipo de enfermería / Solid waste of health services: a photograph of the commitment of nursing staff

O presente trabalho investigou os conhecimentos e atitudes dos profissionais da equipe de enfermagem do Hospital de Clínicas de Porto Alegre (HCPA), Rio Grande do Sul, em relação ao descarte dos resíduos sólidos dos serviços de saúde (RSSS). Realizou-se uma pesquisa de natureza exploratória descritiva, através de uma abordagem qualitativa. Os dados foram obtidos a partir de entrevistas semi-estruturadas aplicadas a 24 profissionais da equipe de enfermagem. Os dados foram categorizados através da análise de conteúdo, tendo sido identificadas quatro categorias: Significado da expressão resíduos sólidos de serviços de saúde; Separação dos resíduos sólidos dos serviços de saúde; Realização do curso/conhecimento e Profissionais que não realizam a separação. Os resultados ratificaram a importância de tratar com maior seriedade a questão apresentada, reforçando a necessidade do acesso às orientações adequadas.

El presente trabajo pretiende investigar los conocimientos y actitudes de los profesionales del equipo de enfermería del Hospital de Clínicas de Porto (HCPA), Rio Grande do Sul, Brasil, en relación al descarte de los residuos sólidos de los servicios de salud (RSSS). Fue realizada una pesquisa de naturaleza exploratoria descriptiva, a través de un abordaje cualitativo. Los datos fueron obtenidos a partir de encuestas semi estructuradas aplicadas a 24 profesionales del equipo de enfermaje. Se buscó la categorización de los datos a través del análisis de contenido. Fueron identificadas cuatro categorías: Significado de la palabra residuos sólidos de servicios de salud; Separación de los residuos sólidos de los servicios de salud; Realización del curso/conocimiento y Profesionales que no realizan la separación. Con los resultados, se ratificó la importancia de tratar con mayor seriedad la cuestión presentada, reforzando la necesidad del acceso a las orientaciones adecuadas.

This work investigated the knowledges and attitudes of the professionals of the nursing group of the Hospital de Clínicas de Porto Alegre (HCPA), Rio Grande do Sul, Brazil, on solid residues in health services (SRHS). Was realized a search for exploratory descriptive nature, through a qualitative approach. The data were obtained from semi-structured interviews applied to 24 professionals of the nursing group. The categorization of the data came through content analysis. Four categories were identified: Meaning of the word solid residues in health services; Separation of solid residues of the health services; Realization of the course/knowledge and professionals who not do the separation. With the results, was confirmed the importance to treat more seriously this question presented, emphasizing the need for access to appropriate guidance.

Evaluation of landfill gas production and emissions in a MSW large-scale Experimental Cell in Brazil.

Landfill gas (LFG) emissions from municipal solid waste (MSW) landfills are an important environmental concern in Brazil due to the existence of several uncontrolled disposal sites. A program of laboratory and field tests was conducted to investigate gas generation in and emission from an Experimental Cell with a 36,659-ton capacity in Recife/PE - Brazil. This investigation involved waste characterisation, gas production and emission monitoring, and geotechnical and biological evaluations and was performed using three types of final cover layers. The results obtained in this study showed that waste decomposes 4-5 times faster in a tropical wet climate than predicted by traditional first-order models using default parameters. This fact must be included when considering the techniques and economics of projects developed in tropical climate countries. The design of the final cover layer and its geotechnical and biological behaviour proved to have an important role in minimising gas emissions to the atmosphere. Capillary and methanotrophic final cover layers presented lower CH(4) flux rates than the conventional layer.

Health risks in areas close to urban solid waste landfill sites.

OBJECTIVE: To evaluate the association between living close to solid waste landfill sites and occurrences of cancer and congenital malformations among populations in their vicinity. METHODS: Deaths among people living in the municipality of São Paulo, Southeastern Brazil, between 1998 and 2002 were selected and geocoded, according to selected causes. Over the period evaluated, there were 351 deaths due to liver cancer, 160 due to bladder cancer and 224 due to leukemia, among adults, 25 due to childhood leukemia and 299 due to congenital malformation, in areas close to landfill sites. Buffer zones of radius 2 km around the 15 sites delimited the areas exposed. Standardized mortality ratios for each outcome were analyzed in Bayesian spatial models. RESULTS: In a general manner, the highest values for the standardized mortality ratios were found in more central areas of the municipality, while the landfill sites were located in more peripheral areas. The standardized mortality ratios did not indicate any excess risk for people living in areas close to solid waste landfill sites in the municipality of São Paulo. For landfill sites in operation, there was a greater risk of bladder and liver cancer, and death due to congenital malformation, but without statistical significance. CONCLUSIONS: No increase in the risk of cancer or congenital malformations was found in areas in the vicinity of urban waste dumps in the municipality of São Paulo. The weak associations and the imprecision of the estimates obtained did not allow any causal relationship to be established.

Percepción del impacto del vertedero final de basuras en la salud y en el ambiente físico y social en Cali / Impact perception on health, social and physical environments of the municipal solid waste disposal site in Cali

Objetivo Describir el impacto auto-percibido en la salud y en el ambiente físico y social entre la población residente aledaña al vertedero de Navarro, el cual recibe los desechos de la ciudad de Cali. Metodología Se llevó a cabo un estudio cualitativo, entre febrero-noviembre de 2006, para explorar las vivencias de los residentes de las zonas aledañas al vertedero de basuras de Navarro. Participaron 16 personas con posición de liderazgo en sus comunidades. Se llevaron a cabo 7 entrevistas individuales semi-estructuradas y un grupo focal con 9 participantes. Se realizó un análisis temático, con el apoyo de redes temáticas, para identificar patrones recurrentes relacionados con la experiencia de vivir cerca del lugar de disposición final de basuras de Cali. Resultados Los participantes en el estudio perciben que los malos olores provenientes del vertedero de Navarro ocasionan principalmente enfermedades respiratorias. Además, se ha creado un estigma de lugar debido a los malos olores, las moscas y a la visibilidad de las basuras. Conclusión No sólo se auto-perciben los efectos del vertedero de basuras de Navarro en la salud física; sino, además, que debido al estigma de lugar se afecta el ambiente físico y social de la población que vive en la zona aledaña al vertedero.

Objective Describing the self-perceived impact on health of people living near to a solid waste disposal site in Cali and on their physical and social environments. Methods In addition to a cohort study, qualitative research was carried out to explore experiences amongst 16 residents in leadership positions in their communities. Seven semi-structured interviews and one focus group were conducted. Thematic analysis was developed using thematic networks to identify recurrent patterns related to theexperience of living in proximity to the solid waste disposal dump. Results Participants perceived respiratory health problems as mainly arising from the sickening odours emanating form the Navarro dump. The area has also developed a bad reputation (“stigma”) because of the exasperating odours, flies and the close view of waste disposal. Conclusions Participants perceived the Navarro dump had a negative impact on their physical health and also that its bad reputation in the neighbourhood had effects on the social and physical environment of people living close to the solid waste disposal dump.

Dengue, related to rubble and building construction in Brazil.

The fast-growing formation of solid waste, resulting from demographic density, presents itself as one of the most pressing problems to be addressed by governments of large cities all over the world. In Rio de Janeiro, 60% of solid waste stems from the construction industry. Although envisaged by under current municipal legislation, no application of policy regarding systematic recycling of this kind of waste exists in fact. Both sanitation experts and epidemiologists highlight that the deficient sanitary system contributes to the growth of endemic breeding sites, which may reach epidemic proportions. In Brazil, over the recent years, there has been an increase of Dengue Fever cases followed by deaths. In the first half of 2008, the State of Rio de Janeiro was plagued by an intense Dengue epidemic. The city of Rio de Janeiro alone accounted for 48.7% of the cases, in absolute values. By drawing upon an analytical method based on the interrelation between health and sanitation, the outcomes herein indicate that the city of Rio de Janeiro bears a direct relation between Dengue incidence rates and rubble formation from construction - measured by the total area built. Thus, there is a strong urge to implement recycling systems out of construction rubble as a sanitation measure in order to promote Dengue incidence reduction.

The socio-demographic, environmental and reservoir factors associated with leptospirosis in an urban area of north-eastern Brazil.

In an ecological study based on the 18 microregions that form the city of Recife, the capital of the Brazilian state of Pernambuco, associations between socio-demographic, environmental and reservoir factors and the incidence of leptospirosis in the city were investigated. Incidence over a 5-year period (2001-2005) and 14 variables were analysed, using central trend and dispersion measurements, Pearson's correlation and multiple linear regression. Variables relating to education, income, housing type, sewage system, rubbish collection and hydrographic factors were found to be significantly correlated with leptospirosis incidence (P<0.05 for each). Just two variables - the proportion of heads of households with incomes less than or equal to the legal minimum (U.S.$83.55/month), and the proportion of households from which rubbish was dumped in skips, lakes, rivers or the sea or on vacant land - explained 60% (P=0.017) of the differences in disease risk observed between the various areas of the city.

[Impact perception on health, social and physical environments of the municipal solid waste disposal site in Cali]. / Percepción del Impacto del Vertedero Final de Basuras en la Salud y en el Ambiente Físico y Social en Cali.

OBJECTIVE: Describing the self-perceived impact on health of people living near to a solid waste disposal site in Cali and on their physical and social environments. METHODS: In addition to a cohort study, qualitative research was carried out to explore experiences amongst 16 residents in leadership positions in their communities. Seven semi-structured interviews and one focus group were conducted. Thematic analysis was developed using thematic networks to identify recurrent patterns related to theexperience of living in proximity to the solid waste disposal dump. RESULTS: Participants perceived respiratory health problems as mainly arising from the sickening odours emanating form the Navarro dump. The area has also developed a bad reputation ("stigma") because of the exasperating odours, flies and the close view of waste disposal. CONCLUSIONS: Participants perceived the Navarro dump had a negative impact on their physical health and also that its bad reputation in the neighbourhood had effects on the social and physical environment of people living close to the solid waste disposal dump.

Estimating national landfill methane emissions: an application of the 2006 Intergovernmental Panel on Climate Change Waste Model in Panama.

This paper estimates national methane emissions from solid waste disposal sites in Panama over the time period 1990-2020 using both the 2006 Intergovernmental Panel on Climate Change (IPCC) Waste Model spreadsheet and the default emissions estimate approach presented in the 1996 IPCC Good Practice Guidelines. The IPCC Waste Model has the ability to calculate emissions from a variety of solid waste disposal site types, taking into account country- or region-specific waste composition and climate information, and can be used with a limited amount of data. Countries with detailed data can also run the model with country-specific values. The paper discusses methane emissions from solid waste disposal; explains the differences between the two methodologies in terms of data needs, assumptions, and results; describes solid waste disposal circumstances in Panama; and presents the results of this analysis. It also demonstrates the Waste Model's ability to incorporate landfill gas recovery data and to make projections. The former default method methane emissions estimates are 25 Gg in 1994, and range from 23.1 Gg in 1990 to a projected 37.5 Gg in 2020. The Waste Model estimates are 26.7 Gg in 1994, ranging from 24.6 Gg in 1990 to 41.6 Gg in 2020. Emissions estimates for Panama produced by the new model were, on average, 8% higher than estimates produced by the former default methodology. The increased estimate can be attributed to the inclusion of all solid waste disposal in Panama (as opposed to only disposal in managed landfills), but the increase was offset somewhat by the different default factors and regional waste values between the 1996 and 2006 IPCC guidelines, and the use of the first-order decay model with a time delay for waste degradation in the IPCC Waste Model.

Mathematical modeling to predict residential solid waste generation.

One of the challenges faced by waste management authorities is determining the amount of waste generated by households in order to establish waste management systems, as well as trying to charge rates compatible with the principle applied worldwide, and design a fair payment system for households according to the amount of residential solid waste (RSW) they generate. The goal of this research work was to establish mathematical models that correlate the generation of RSW per capita to the following variables: education, income per household, and number of residents. This work was based on data from a study on generation, quantification and composition of residential waste in a Mexican city in three stages. In order to define prediction models, five variables were identified and included in the model. For each waste sampling stage a different mathematical model was developed, in order to find the model that showed the best linear relation to predict residential solid waste generation. Later on, models to explore the combination of included variables and select those which showed a higher R(2) were established. The tests applied were normality, multicolinearity and heteroskedasticity. Another model, formulated with four variables, was generated and the Durban-Watson test was applied to it. Finally, a general mathematical model is proposed to predict residential waste generation, which accounts for 51% of the total.

Recycling potential of urban solid waste destined for sanitary landfills: the case of Indaiatuba, SP, Brazil.

The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of São Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000kgday(-1). A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks.

Comparative analysis of hazardous household waste in two Mexican regions.

Household hazardous waste (HHW) generation in two Mexican regions was examined, a northern region (bordering with the USA) and a central region. The aim of this work was to determine the dynamics of solid waste generation and to be able to compare the results of both regions, regarding consumption patterns and solid waste generation rates. In the northern region, household solid waste was analysed quantitatively. In order to perform this analysis, the population was categorized into three socioeconomic strata (lower, middle, upper). Waste characterization revealed the presence of products that give origin to household hazardous waste. In the northern region (Mexicali city), household hazardous waste comprised 3.7% of municipal solid waste, the largest categories in this fraction were home care products (29.2%), cleaning products (19.5%) and batteries and electronic equipment (15.7%). In the central region, HHW comprised 1.03% of municipal solid waste; the main categories in this fraction were represented by cleaning products (39%), self care products (27.3%), and insecticides (14.4%). In Mexicali, the socioeconomic study demonstrated that the production of HHW is independent of the income level. Furthermore, the composition of the solid waste stream in both regions suggested the influence of another set of variables such as local climate, migration patterns and marketing coverage. Further research is needed in order to establish the effect of low quantities of HHW upon the environment and public health.