Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis

Background: access to safe drinking-water is a fundamental requirement for good health and is also a human right. Global access to safe drinking-water is monitored by WHO and UNICEF using as an indicator “use of an improved source,” which does not account for water quality measurements. Our objectives were to determine whether water from “improved” sources is less likely to contain fecal contamination than “unimproved” sources and to assess the extent to which contamination varies by source type and setting.Methods and findings: studies in Chinese, English, French, Portuguese, and Spanish were identified from online databases, including PubMed and Web of Science, and grey literature. Studies in low- and middle-income countries published between 1990 and August 2013 that assessed drinking-water for the presence of Escherichia coli or thermotolerant coliforms (TTC) were included provided they associated results with a particular source type. In total 319 studies were included, reporting on 96,737 water samples. The odds of contamination within a given study were considerably lower for “improved” sources than “unimproved” sources (odds ratio [OR] = 0.15 [0.10–0.21], I2 = 80.3% [72.9–85.6]). However over a quarter of samples from improved sources contained fecal contamination in 38% of 191 studies. Water sources in low-income countries (OR = 2.37 [1.52–3.71]; p<0.001) and rural areas (OR = 2.37 [1.47–3.81] p<0.001) were more likely to be contaminated. Studies rarely reported stored water quality or sanitary risks and few achieved robust random selection. Safety may be overestimated due to infrequent water sampling and deterioration in quality prior to consumption.Conclusion: access to an “improved source” provides a measure of sanitary protection but does not ensure water is free of fecal contamination nor is it consistent between source types or settings. International estimates therefore greatly overstate use of safe drinking-water and do not fully reflect disparities in access. An enhanced monitoring strategy would combine indicators of sanitary protection with measures of water qualit

Field-testing solutions for drinking water quality monitoring in low- and middle-income regions and case studies from Latin American, African and Asian countries

Funding Information: This study is part of SAFEWATER Devices Translation and Implementation project supported by the Global Challenges Research Fund ( GCRF ) Global Research Translation Awards, UK Research and Innovation ( SAFEWATER Translate, EPSRC Grant Reference EP/T015470/1 ).Peer reviewedPublisher PD

Investigating industrial effluent impacts on municipal wastewater treatment plant

Industrial effluents with high concentrations of heavy metals are widespread pollutants of great concerns as they are known to be persistent and non-degradable. Continuous monitoring and treatment of the effluents become pertinent because of their impacts on wastewater treatment plants. The aim of this study is to determine the correlation between heavy metal pollution in water and the location of industries in order to ascertain the effectiveness of the municipal waste water treatment plant. Heavy metal identification and physico-chemical analysis were done using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and multi-parameter probe respectively. Correlation coefficients of the measured values were done to investigate the effect of the industrial effluents on the treatment plants. Heavy metal resistant bacteria were identified and characterised by polymerase chain reaction and sequencing. Leeuwkuil wastewater treatment plants were effective in maintaining temperature, pH, and chemical oxygen demand within South Africa green drop and SAGG Standards whereas the purification plant was effective in maintaining the values of Cu, Zn, Al, temperature, BOD, COD, and TDS within the SANS and WHO standard for potable water. This findings indicated the need for the treatment plants to be reviewed.The industrial wastewater were identified as a point source of heavy metal pollution that influenced Leeuwkuil wastewater treatment plants and the purification plants in Vaal, Vereenining South Africa. Pseudomonas aeruginosa, Serratia marcescens, Bacillus sp. strain and Bacillus toyonensis that showed 100% similarity were found to be resistant to Al, Cu, Pb and Zn. These identified bacteria can be considered for further study in bioremediation.Environmental SciencesM. Sc. (Environmental Science

Sustainable wastewater management:exploring the option of greywater reuse in a developing country – Ghana

The research explored greywater reuse strategies in a developing country. Quality and quantity estimation of greywater was assessed which established the detrimental effect of unregulated discharge of greywater into the environment. The study experimented the use of a locally produced adsorbent in reducing targeted contaminants in greywater and further studied associated behaviour relating to users. The local material was successful in reducing the targeted pollutant to the recommended guideline values. The study also established that, preference for greywater reuse was more geared toward non-potable uses. The research concludes that to convince household heads to adopt greywater treatment and reuse systems, specific drivers of intentions must be addressed in the campaign

Integrated school garden, nutrition, water, sanitation and hygiene interventions for improving nutritional and health status of schoolchildren in Nepal

Background: Malnutrition occurs at all stages of the lifecycle. However, there is little information on malnutrition during school age. The concentration of malnutrition in Asia is greater than anywhere else on Earth. It is reported that 156 million children are stunted, 50 million children are wasted and more than 50% of the 146 million underweight children in the world are living in the South Asia. Malnutrition is a major underlying cause of child mortality within Nepal and anaemia among infants and children is high. In Nepal, 41% percent of children were suffering from chronic malnutrition in 2011. Similarly, iron-deficiency anaemia is one of the top ten leading causes of years of life with disability among all age groups. The dietary risks, malnutrition, unsafe water, sanitation and hygiene (WASH) are among the top ten causes of disability-adjusted life years (DALYs). Intestinal parasitic infections are among common public health problems of children in Nepal and the infection rate has primarily been attributed to the appalling unhygienic environmental conditions. The intestinal parasitic infection and amoebic dysentery stand second among the top ten causes of hospital visits within the country. According to the Global Burden of Diesease Study (GBD) and the World Health Organisation (WHO)/United Nations Chidren’s Fund (UNICEF) “Joint Monitoring Programme for Water Supply and Sanitation”, 8% of deaths in children aged 8-14 years in Nepal, were caused by diarrhoeal diseases and attributed to inadequate WASH condition as a primary risk factor. Nutrition as a cross-cutting theme is closely interlinked with multifactorial determinants. Malnutrition is an outcome of poor nourishment (i.e. inadequate, unbalanced or excessive nourishment), while other factors, such as illness and poor sanitation also contribute to malnutrition. Three interacting groups of underlying factors contribute, in turn, to inadequate dietary intake and infectious diseases: household food insecurity; inadequate maternal and child care; and poor health and environmental services. Hence to address these challenges, the more recent strategic frameworks call for a combination of nutrition-sensitive and nutrition-specific interventions, including synergies between agriculture, nutrition and WASH. However, there is lack of evidence about the contribution of integrated agriculture, nutrition and WASH interventions in minimising malnutrition and anaemia. A project entitled “Vegetables go to School: improving nutrition through agricultural diversification” (VgtS) has been developed to improve schoolchildren’s nutrition, through introducing school vegetable gardens and additional complementary school-based health interventions. The VgtS project is funded by the Swiss Agency for Development and Cooperation (SDC) and was implemented in five countries (i.e. Burkina Faso, Bhutan, Indonesia, Nepal and the Philippines). This PhD thesis was embedded in the VgtS project in Nepal as an operational research study to contribute to the outcome 3 of the project; generating increased knowledge on how school vegetable gardens contribute to improved nutrition and health of schoolchildren, as well as the interaction with WASH. Goal and objectives: This PhD thesis aims at assessing the effects of complementary school garden, nutrition and WASH interventions on nutrition and health status of schoolchildren in Nepal. In order to achieve this aim, the following four specific objectives were pursued: (i) to investigate the WASH conditions at the unit of selected schools, households and community in the districts of Dolakha and Ramechhap in Nepal; (ii) to determine the local epidemiology of malnutrition and intestinal parasitic infection among schoolchildren; (iii) to assess the knowledge, attitude and practices (KAP) of schoolchildren and caregivers regarding nutrition and WASH conditions; and (iv) to evaluate the effects of supplemented complementary school gardens, nutrition and WASH interventions on children nutritional and health status. Methods: The study was designed as a cluster-randomised controlled trial (RCT). The trial included 12 schools randomised into three arms: arm 1 implementing a school garden (SG); arm 2 with additional WASH and nutrition complementary interventions (SG+WASH); and arm 3 without any interventions (control) in the districts of Dolakha and Ramechhap of Nepal. The baseline cross-sectional survey was conducted between March and May 2015 among 705 children aged 8-16 years. The pack of complementary interventions to the school garden has been implemented after the baseline survey. A follow-up survey was conducted within the same cohort of children one year after the baseline survey, in June 2016. In both surveys, questionnaires were administered to evaluate WASH conditions at the level of schools, households and communities. Dietary intake was assessed using a food frequency questionnaire and 24-hours (24-h) recall. Haemoglobin (Hb) levels were measured using a HaemoCue digital photometer. Stool samples were subjected to wet-mount, Kato-Katz and formalin-ether concentration methods for the diagnosis of intestinal parasitic infections. Water quality was assessed using the Delagua testing kit and flame atomic absorption method. Results: A total of 75% of school drinking water source samples and 77% point-of-use samples at schools, 40% water source samples in the community, and 27% point-of-use samples at household levels were contaminated with thermo-tolerant coliforms (TTC). The values of water samples for pH (6.8–7.6), free and total residual chlorine (0.1–0.5 mg/L), mean lead concentration (0.01 mg/L), and mean arsenic concentration (0.05 mg/L) were within national drinking water quality standards. The presence of domestic animals roaming inside schoolchildren’s homes was significantly associated with drinking water contamination (adjusted odds ratio (aOR): 1.64; 95% confidence interval (CI): 1.08–2.50; p=0.02). Overall, 27.0% of the participating children were stunted and 11.3% were wasted. We observed a significant difference of stunting and wasting between boys and girls (stunting: 31.6% for boys versus 22.8% for girls, p=0.01; wasting: 15.9% for boys versus 7.1% for girls, p=0.01). We also found a significant difference in stunting between the two districts where Dolakha had a higher stunting rate than Ramechhap (30.1% in Dolakha versus 15.7% in Ramechhap; p=0.01). The overall prevalence of anaemia was 23.9% at baseline. The lack of meals prepared in the households (aOR=2.36, 95% CI: 1.14-4.92; p=0.01) and not having supper (aOR=3.46, 95% CI: 1.09-11.03; p=0.04) were significantly associated with anaemia. The dietary diversity scores were lower among anaemic compared to non-anaemic children. Consumption of vitamin A-rich fruits and vegetables were negatively associated with anaemia, but not significantly so. More than half (55.0%) of the children had at least one sign (e.g., loss of hair pigment) of nutritional deficiency. The overall prevalence of intestinal parasite infections was 39.7%. Trichuris trichiura and Giardia intestinalis were the predominant helminth and intestinal protozoa species, with a prevalence of 31.0% each. Children from households lacking soap for hand washing were at higher odds of intestinal parasite infections (aOR=1.81; 95% CI: 1.13-2.89; p=0.01), while children from households without freely roaming domestic animals showed lower odds of G. intestinalis compared to those households with such animals (aOR 0.52; 95% CI: 0.33-0.83; p=0.01). We found considerable morbidity among the surveyed children, including fever (31%) and watery diarrhoea (22%). Water contamination with TTC did not emerge as significant risk factor for intestinal parasitic infections. This study shows that the diet of surveyed schoolchildren mainly comprised of starchy staples and legumes. The mean consumption of animal product per week was low (1.96 for poultry, 1.18 for red meat, 0.81 for fish and 0.91 for milk products). Five dietary patterns were derived: mixed food, vegetables and lentils, milk products, salty snacks, and processed food pattern scores. The vegetables and lentils pattern scores were negatively associated with stunting (aOR 0.84; 95% CI: 0.66-1.08, p=0.17) after adjusting for regional differences, demographic and behaviour risk factors, however not significant. At the follow-up, stunting was slightly reduced in complementary intervention arm (SG+WASH) (20% to 18%; p=0.92, compared to control) contrary to a slight increase in the school garden arm (SG) (18% to 20%; p=0.54, compared to control) and control (20% to 19%). Anaemia slightly decreased in SG+WASH (33% to 32%; p<0.01, compared to control) and markedly increased in the control arm (23% to 42%) and the SG (21% to 44%; p=0.56, compared to control). Handwashing with soap (i) before eating and (ii) after defecation strongly increased in SG+WASH arm (i) 74% to 97%; p=0.01 compared to control with 78% to 84%; (ii) 77% to 99%; p=0.36 compared to control with 78% to 92%. While the prevalence of parasite infections significantly declined in SG+WASH arm (37% to 9%; p<0.01, compared to control) and a minor decline in SG (34% to 27%; p=0.42, compared to control) and stable in the control arm (44% to 42%). Conclusions: Malnutrition, anaemia and intestinal parasitic infections, particularly soil-transmitted helminths, are of an important public health concern among schoolchildren in the districts of Dolakha and Ramechhap, Nepal. Our complementary interventions implemented in schools and households, increased children’s awareness on fruits and vegetables intake, reduced anaemia, stunting and intestinal parasitic infections among schoolchildren within one year. Hence, this study showed that a combination of agricultural, nutritional and WASH-based interventions, readily delivered through the school platform, could improve schoolchildren’s health and nutritional status. Our findings call for a sustained joint national effort for integrating agriculture, nutrition and WASH interventions at schools, households and communities levels

Removal rate of endocrine disruptors (phthalates and phenolic compounds) in effluents of selected wastewater treatment plants operated under different treatment technologies in the Eastern Cape, South Africa

The presence of phthalate esters (PAEs) and certain phenolic compounds widely known as endocrine disruptors in environmental waters such as treated wastewaters constitutes health hazard to human and aquatic lives. Unfortunately, wastewater treatment plants (WWTPs) only partially remove these synthetic chemical compounds from wastewater. In order to forestall the health challenge faced by rural dwellers, which rely on surface water for their daily needs, the present study embarked on investigating these endocrine disruptors in Municipal wastewater in the Amathole and Buffalo Districts in the Eastern Cape, South Africa and their removal rate by different WWTP technologies. One WWTP each from Adelaide, Alice, Bedford, Berlin and Seymour, using activated sludge (AS), trickling filter (TF), and oxidation pond (OP) technology were randomly selected. Some physicochemical parameters of these wastewaters were determined on-site using standard methods and the extraction method for endocrine disrupting chemicals (EDCs) in water was validated using solid phase extraction (SPE). Extracts were analysed using gas chromatography-mass spectrometer (GC-MS). Nine phenolic compounds; phenol (PH), 2-chlorophenol (2-CP), 2,4-dimethylphenol (2,4-DMP), 2,4-dichlorophenol (2,4-DCP), 4-chloro-3-methylphenol (4-C-3MP), 2-nitrophenol (2-NP), 4-nitrophenol (4-NP), pentachlorophenol (PCP), 2,4,6-trichlorophenol (2,4,6-TCP) and six priority PAEs namely; dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di(2-ethyl hexyl) phthalate (DEHP), and di-n-octyl phthalate (DOP) were the investigated EDCs. PAEs were extracted from dried sludge samples in an ultrasonic bath using dichloromethane. Some physicochemical parameters of the wastewater assessed revealed that treatment processes of AS, TF, and OP reduced turbidity, total suspended solids (TSS), total dissolved solids (TDS), and electrical conductivity (EC) while dissolved oxygen (DO) was increased. There was no significant influence on temperature and pH across the sampling points. Except for turbidity, the quality of effluent released mostly falls within South Africa standard limits for domestic and recreational water. The nine phenolic compounds were detected across the sampling points for all the WWTPs at different frequencies. The prominent phenolic compounds were 2-NP, 4-C-3MP, PCP, and 2,4-DMP with concentrations ranging from 3.3 (2,4-DMP) – 83.0 μgL-1 (4-C-3MP) in the influents. However, their concentrations in the effluents and receiving water bodies were below tolerable limits of 5 μgL-1 set by the US Environmental Protection Agency (USEPA) and the European Union (EU) for domestic use. The removal capacities of the WWTPs varied between 33 and 96 percent. The six PAEs were detected in all water samples from all the WWTPs. DBP was the most abundant compound in all the sampling points and sometimes DEHP in some receiving waters. The maximum detection for DBP in influent, effluent, downstream and sludge were 2,488 μgL-1 (Alice), 26.47 μgL-1 (Adelaide), 115.3 μgL-1 (Seymour) and 1,249 μg/g dw (Alice), respectively. DEHP was the highest detected PAE in the upstream 17.53 μgL-1 (Seymour). There was a notable reduction of all PAEs in the final effluent with a removal efficiency which varied as much as 61.9 – 99.5 percent except for AS in Seymour which operated a single tank system (27.3 - 93.7 percent). Removal mechanisms continued more on adsorption on settling particles and sludge than biodegradation as this study found a high positive correlation between TSS, turbidity and PAEs removal. The concentrations of PAEs detected in the receiving waters were above 1.3 and 3μgL-1 limit standard set by the EU and USEPA, respectively for DEHP in surface water. Similarly, the average concentrations of DBP, BBP, DEHP and DOP which vary as much as 25.97 (BBP) – 1249 μg/g d.w (DBP) in sludge samples were above EU legislation of 100 μg/g d.w. for agricultural use. AS technology, showed a better performance in the removal of PAEs (77 – 99 percent), followed by TF (76 – 98 percent) and OP (61 – 98 percent). In conclusion, the PAE concentration in the WWTP effluents impacted negatively on the receiving water bodies and sewage sludge unlike the phenolic compounds that were notably reduced below the acceptable limits. Perhaps, due to the meagre amounts of the phenolic compounds that was detected entering the WWTPs. In order to avert the potential health risk to aquatic organisms’ and rural dwellers, it is exigent that constituted authorities gather more information on micro-pollutants in the environment as a basis for regulations on the use of these dangerous chemicals in industries

Wastewater irrigation and health: assessing and mitigating risk in low-income countries

Wastewater irrigation / Public health / Health hazards / Risk assessment / Epidemiology / Sewage sludge / Excreta / Diseases / Vegetables / Leaf vegetables / Economic impact / Wastewater treatment / Irrigation methods / Developing countries

Drinking Water Quality and Human Health

The quality of drinking water is paramount for public health. Despite important improvements in the last decades, access to safe drinking water is not universal. The World Health Organization estimates that almost 10% of the population in the world do not have access to improved drinking water sources. Among other diseases, waterborne infections cause diarrhea, which kills nearly one million people every year, mostly children under 5 years of age. On the other hand, chemical pollution is a concern in high-income countries and an increasing problem in low- and middle-income countries. Exposure to chemicals in drinking water may lead to a range of chronic non-communicable diseases (e.g., cancer, cardiovascular disease), adverse reproductive outcomes, and effects on children’s health (e.g., neurodevelopment), among other health effects. Although drinking water quality is regulated and monitored in many countries, increasing knowledge leads to the need for reviewing standards and guidelines on a nearly permanent basis, both for regulated and newly identified contaminants. Drinking water standards are mostly based on animal toxicity data, and more robust epidemiologic studies with accurate exposure assessment are needed. The current risk assessment paradigm dealing mostly with one-by-one chemicals dismisses the potential synergisms or interactions from exposures to mixtures of contaminants, particularly at the low-exposure range. Thus, evidence is needed on exposure and health effects of mixtures of contaminants in drinking water. Finally, water stress and water quality problems are expected to increase in the coming years due to climate change and increasing water demand by population growth, and new evidence is needed to design appropriate adaptation policies.This Special Issue of International Journal of Environmental Research and Public Health (IJERPH) focuses on the current state of knowledge on the links between drinking water quality and human health

Impact of microbial and physico-chemical qualities of treated wastewater effluent on receiving water bodies in Durban.

Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2013.Increase in magnitude of the global freshwater crisis together with the constantly changing demographics, hydrological variability and rapid urbanization will allow for continuous over exploitation of existing water resources, in an attempt to satisfy the rising socioeconomic demands. Increasing pressure on existing wastewater treatment plants, together with inefficient hygiene practices have exacerbated the nutrient and microbiological loads constantly entering surrounding water systems. This, coupled with the use of outdated guidelines has resulted, not only in an increase in waterborne related diseases but also an increase in waterborne-disease-related deaths. The current study investigated the physicochemical and microbiological quality of treated effluent from two independent wastewater treatment plants as well as their impact on the receiving watershed within Durban, South Africa over a one year period. Microbiological and physicochemical profiles were determined using standard methods whilst conventional PCR was used for the seasonal detection of human enteric viruses. Monthly variations were observed for all parameters with eight and six out of 12 month samples exhibiting increases in turbidity at the discharge point for the NWWTP and NGTW respectively, relative to before chlorination. Similarly, increases in nitrate and phosphate levels at the discharge point were also noted with the highest being recorded during December (215.23%) and September (12.21%) respectively. Temperature profiles ranged between 12 – 26 °C and 12.7 – 26 °C for the NWWTP and receiving Umgeni River whilst for the NGTW and receiving Aller River, it ranged between 16.5 – 26 °C and 12 – 25.7 °C respectively. Seasonal averages revealed relatively high COD values downstream of the Umgeni River during winter (263.22 mg/l) and spring (177.93 mg/l). Eight out of twelve samples exhibited increases in turbidity at the discharge point for the NWWTP with the highest values obtained during April (76.43 NTU). Significant positive correlations (p ≤ 0.05) were observed upstream and downstream of the Umgeni River between temperature and BOD (r = 0.624); turbidity (r = 0.537); TDS (r = 0.437); TSS (r = 0.554) and DO (r = 0.516). Percentage reduction of bacterial indicators at the discharge point ranged between 0.52 – 100% and 41.56 – 100% across the sampling period for the NWWTP and NGTW, respectively. Treated effluent from both plants did not meet the required guidelines, with a 100% reduction in the faecal coliform load being detected only during October 2012 for both plants. In addition, higher levels of indicator bacteia were observed at the discharge point for the NWWTP during February 2013 with observed counts (in CFU/ml) as high as 12.27 x 103; 6.61 x 103; 2.99 x103; 1.6 x 103 and 1.17 x103 for total coliforms, E.coli, faecal coliforms, faecal streptococci and enterococci, respectively. Similarly, higher levels of both somatic and F-RNA bacteriophages were detected during April (106.67 PFU/ml), May (309.33 PFU/ml). June (346.67 PFU/ml) and August (126.67 PFU/ml) compared to samples collected before chlorination for the NWWTP. Enteroviruses were detected in 100% of unchlorinated final effluent samples, 87.5% of chlorinated final effluent and 93.75% of receiving river samples whilst human adenoviruses were detected in 50% of final effluent samples before chlorination, 62.5% in samples collected at the discharge point and 62.5% of river water samples. This study revealed that whilst the independent treatment plants monitored, exhibited effluent qualities that met acceptable standards for some parameters such as pH and temperature, the effluent quality fell short of other standard requirements. Ensuring efficient surveillance and management of existing treatment plants coupled with guideline revision and monitoring compliance is imperative in preventing further risk of pollution to both the environment and human health.Table of content is missing in the digital version