Randomized Controlled Trials in Environmental Health Research: Unethical or Underutilized? PLoS Med, Jan 2015.

Authors: Ryan W. Allen , Prabjit K. Barn, Bruce P. Lanphear

Randomized controlled trials are standard practice in clinical and pharmaceutical research but have not been embraced by environmental health researchers. Greater use of the RCT design would complement the tremendous contributions made by other methods—including both observational epidemiology and toxicology—to our understanding of environmental risks and the development of environmental health policy.

Researchers, academic institutions, and funding agencies have a role to play in expanding the use of RCTs in environmental health research. Researchers should think creatively about potential interventions and consider the RCT as a possible study design to test their specific research question. Funding agencies should allocate money specifically for randomized studies of environmental interventions.

In addition to its scientific advantages, this would provide the additional benefit of encouraging research that aims not only to identify problems but also to identify possible solutions. Ethical issues must be considered carefully, and while institutional ethics approval is necessary, it is not sufficient to ensure that the research is conducted ethically. The RCT design has important limitations and is not applicable to all research questions, so observational studies will, and should, remain the workhorse in environmental health research.

Nevertheless, RCTs can help advance the field of environmental health by creating new knowledge of exposure–health relationships, providing more definitive evidence of causality, identifying efficacious interventions to reduce or eliminate exposure and health risks, and countering the perception that environmental risks are evaluated with inadequate rigor.

A rapid assessment of drinking water quality in informal settlements after a cholera outbreak in Nairobi, Kenya. Journal of Water and Health, In Press, Uncorrected Proof, 2014 | doi:10.2166/wh.2014.173

Authors – Elizabeth Blanton, Natalie Wilhelm, Ciara O’Reilly, Everline Muhonja, Solomon Karoki, Maurice Ope, Daniel Langat, Jared Omolo, Newton Wamola, Joseph Oundo, Robert Hoekstra, Tracy Ayers, Kevin De Cock, Robert Breiman, Eric Mintz and Daniele Lantagne

Populations living in informal settlements with inadequate water and sanitation infrastructure are at risk of epidemic disease. In 2010, we conducted 398 household surveys in two informal settlements in Nairobi, Kenya with isolated cholera cases. We tested source and household water for free chlorine residual (FCR) and Escherichia coli in approximately 200 households. International guidelines are ≥0.5 mg/L FCR at source, ≥0.2 mg/L at household, and <1 E. coli/100 mL.

In these two settlements, 82–38% of water sources met FCR guidelines; and, 7% and 8% were contaminated with E. coli, respectively. In household stored water, 82% and 35% met FCR guidelines and 11% and 32% were contaminated with E. coli, respectively. Source water FCR ≥0.5 mg/L (p = 0.003) and reported purchase of a household water treatment product (p = 0.002) were associated with increases in likelihood that household stored water had ≥0.2 mg/L FCR; which was associated with a lower likelihood of E. coli contamination (p < 0.001).

These results challenge the assumption that water quality in informal settlements is universally poor and the route of disease transmission, and highlight that providing centralized water with ≥0.5 mg/L FCR or (if not feasible) household water treatment technologies reduces the risk of waterborne cholera transmission in informal settlements.

Uploaded on Dec 30, 2014 – Toxic synthetic chemicals such as pesticides and pharmaceutical residues are a major threat to drinking water safety worldwide. Unfortunately, major international water development initiatives focus exclusively on microbial pathogens (the most immediate threat to health) while neglecting synthetic chemical toxins. Low-cost, environmentally sustainable and locally managed treatment technologies are needed to protect human health in impoverished, rural and remote communities.

Our ongoing research demonstrates the potential of char made from surplus biomass (biochar) as an effective sorbent for chemical toxins. We have shown that highly adsorbing biochar can be produced from surplus biomass using low-tech, efficient and environmentally friendly gasifier drum ovens. Our work advances sustainable and locally managed treatment systems employing adsorbent biochar as an effective, affordable and accessible means for providing drinking water that is microbiologically and chemically safe to households and communities in remote and impoverished regions of the world.

Hand-to-mouth contacts result in greater ingestion of feces than dietary water consumption in Tanzania: A quantitative fecal exposure assessment model. Environ. Sci. Technol., DOI: 10.1021/es505555f, Publication Date (Web): January 5, 2015

Authors: Mia Catharine Morgan Mattioli , Jennifer Davis , and Alexandria B. Boehm

Diarrheal diseases kill 1800 children under the age of five die each day, and nearly half of these deaths occur in sub-Saharan Africa. Contaminated drinking water and hands are two important environmental transmission routes of diarrhea-causing pathogens to young children in low-income countries. The objective of this research is to evaluate the relative contribution of these two major exposure pathways in a low-income country setting. A Monte Carlo simulation was used to model the amount of human feces ingested by children under five years old from exposure via hand-to-mouth contacts and stored drinking water ingestion in Bagamoyo, Tanzania.

Child specific exposure data were obtained from the USEPA 2011 Exposure Factors Handbook, and fecal contamination was estimated using hand rinse and stored water fecal indicator bacteria concentrations from over 1200 Tanzanian households. The model outcome is a distribution of a child’s daily dose of feces via each exposure route.

The model results show that Tanzanian children ingest a significantly greater amount of feces each day from hand-to-mouth contacts than from drinking water, which may help elucidate why interventions focused on water without also addressing hygiene often see little to no effect on reported incidence of diarrhea.

Critical parameters in the production of ceramic pot filters for household water treatment in developing countriesJournal of Water and Health, In Press, Uncorrected Proof © IWA Publishing 2014 | doi:10.2166/wh.2014.090

A. I. A. Soppe, S. G. J. Heijman, I. Gensburger, A. Shantz, D. van Halem, J. Kroesbergen, G. H. Wubbels and P. W. M. H. Smeets

Aqua for All Foundation, Koningskade 40, The Hague 2596 AA, the Netherlands E-mail: gsoppe@planet.nl
Department of Water Management, Delft University of Technology, Stevinweg 1, Delft 2628 CN, the Netherlands
Engineers Without Borders Australia, 99 Howard Street, North Melbourne, VIC, Australia and Downer Ltd., 133 Main South Road, PO Box 13031, Dunedin 9052, New Zealand
Resource Development International Cambodia, No. 50A, Phum Prek Thom Sangkat Kbal Koh, Khan Mean Chey, Phnom Penh, Kingdom of Cambodia
Het Waterlaboratorium, J.W. Lucasweg 2, Haarlem 2031 BE, the Netherlands
Waterlaboratorium Noord, Rijksstraatweg 85, Glimmen 9756 AD, the Netherlands
KWR Watercycle Research Institute, Groningenhaven 7, Nieuwegein 3433 PE, the Netherlands

The need to improve the access to safe water is generally recognized for the benefit of public health in developing countries. This study’s objective was to identify critical parameters which are essential for improving the performance of ceramic pot filters (CPFs) as a point-of-use water treatment system. Defining critical production parameters was also relevant to confirm that CPFs with high-flow rates may have the same disinfection capacity as pots with normal flow rates. A pilot unit was built in Cambodia to produce CPFs under controlled and constant conditions.

Pots were manufactured from a mixture of clay, laterite and rice husk in a small-scale, gas-fired, temperature-controlled kiln and tested for flow rate, removal efficiency of bacteria and material strength. Flow rate can be increased by increasing pore sizes and by increasing porosity. Pore sizes were increased by using larger rice husk particles and porosity was increased with larger proportions of rice husk in the clay mixture.

The main conclusions are larger pore size decreases the removal efficiency of bacteria; higher porosity does not affect the removal efficiency of bacteria, but does influence the strength of pots; flow rates of CPFs can be raised to 10–20 L/hour without a significant decrease in bacterial removal efficiency.

Microbial quality of domestic water: following the contamination chain in a rural township in Kenya. Journal of Water, Sanitation and Hygiene for Development, In Press, Uncorrected Proof © IWA Publishing 2014 | doi:10.2166/washdev.2014.070

Authors: Pauline W. Macharia, Paul T. Yillia, Wairimu A. Muia, Denis Byamukama and Norbert Kreuzinger

Department of Biological Sciences, Egerton University, Njoro Campus, P.O. Box 536-20115 Egerton, Kenya E-mail: macharia.pauline@yahoo.com
International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg A-2361, Austria
WSS Services (U) Ltd, P.O. Box 27755 Kampala, Uganda
Resources & Waste Management, Vienna University of Technology, Institute for Water Quality, Karlsplatz 13/226 Vienna, Austria

A study was undertaken in Njoro Township, Kenya to evaluate the extent to which drinking water was subjected to post-collection faecal contamination in low-income and high-income households. Boreholes were the main drinking water sources, accounting for roughly 70% singular access. The microbial quality of drinking water from the boreholes deteriorated from the point-of-collection through conveying containers of small-scale water vendors to household storage containers, irrespective of their income status.

The densities of Escherichia coli (EC) were relatively low at the point-of-collection – median (M): 18 CFU/100 mL, range (R): 0–220, n = 60 – increasing considerably in the containers of water vendors (M: 290 CFU/100 mL, R: 30–350) and slightly (M: 360 CFU/100 mL, R: 0–520) between vendors and low-income households, many of whom used the services of vendors unlike high-income households who relied on a piped system on premises (M: 40 CFU/100 mL, R: 0–500).

Post-collection contamination was high in low-income households compared to high-income households but differences were not significant between the two household categories with and without household water treatment (HWT). Different HWT methods in the two household categories significantly reduced faecal contamination, but unhygienic handling and poor storage practices afterwards caused recontamination. HWT and behavioural change measures need not selectively target household groups solely on the basis of their income status.

Assessing the Consistency and Microbiological Effectiveness of Household Water Treatment Practices by Urban and Rural Populations Claiming to Treat Their Water at Home: A Case Study in Peru. PLoS One, Dec 2014.

Authors: Ghislaine Rosa, Maria L. Huaylinos, Ana Gil, Claudio Lanata, Thomas Clasen

Background - Household water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it. These estimates, however, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice—key factors for reducing pathogen exposure and achieving health benefits. The objective of this study was to examine how HWT practices are actually performed by households identified as HWT users, according to international monitoring standards.

Methods and Findings - We conducted a 6-month case study in urban (n = 117 households) and rural (n = 115 households) Peru, a country in which 82.8% of households report treating their water at home. We used direct observation, in-depth interviews, surveys, spot-checks, and water sampling to assess water treatment practices among households that claimed to treat their drinking water at home. While consistency of reported practices was high in both urban (94.8%) and rural (85.3%) settings, availability of treated water (based on self-report) at time of collection was low, with 67.1% and 23.0% of urban and rural households having treated water at all three sampling visits. Self-reported consumption of untreated water in the home among adults and children <5 was common and this was corroborated during home observations. Drinking water of self-reported users was significantly better than source water in the urban setting and negligible but significantly better in the rural setting. However, only 46.3% and 31.6% of households had drinking water <1 CFU/100 mL at all follow-up visits.

Conclusions - Our results raise questions about the usefulness of current international monitoring of HWT practices and their usefulness as a proxy indicator for drinking water quality. The lack of consistency and sub-optimal microbiological effectiveness also raises questions about the potential of HWT to prevent waterborne diseases.

Need for certification of household water treatment products: examples from Haiti. Trop Med Int Health. 2014 Dec 1. doi: 10.1111/tmi.12445.

Authors: Murray A1, Pierre-Louis J, Joseph F, Sylvain G, Patrick M, Lantagne D. Author information: 1Tufts University Civil and Environmental Engineering, Department.Medford, MA, USA.

OBJECTIVE: To evaluate four chemical treatment products currently seeking approval in Haiti.

METHODS: Household water treatment (HWT) products were evaluated at the certification process validation stage by verifying international product certifications confirming treatment efficacy and reviewing laboratory efficacy data against WHO HWT microbiological performance targets; and at the approval stage by confirming product composition, evaluating treated water chemical content against national and international drinking water quality guidelines, and reviewing packaging for dosing ability and usage directions in Creole.

RESULTS: None of the four evaluated products fulfilled validation or approval stage requirements. None was certified by an international agency as efficacious for drinking water treatment, and none had data demonstrating its ability to meet WHO HWT performance targets. All product sample compositions differed from labeled composition by >20%, and no packaging included complete usage directions in Creole.

CONCLUSIONS: Product manufacturers provided information that was inapplicable, did not demonstrate product efficacy, and was insufficient to ensure safe product use. Capacity building is needed with country regulatory agencies to objectively evaluate HWT products. Products should be internationally assessed against WHO performance targets and also locally approved, considering language, culture, and usability, to ensure effective HWT.

Influence of solar water disinfection on immunity against cholera – a review. Journal of Water and Health Vol 12 No 3 pp 393–398 2014.

Authors: Cornelius Cano Ssemakalu, Eunice Ubomba-Jaswa, Keolebogile Shirley Motaung and Michael Pillay.
Faculty of Applied and Computer Sciences, Vaal University of Technology, Vanderbijlpark 1900, South Africa E-mail: mpillay@vut.ac.za. Council for Scientific and Industrial Research, Natural Resource and the Environment, P.O. Box 395, Pretoria 0001, South Africa. Department of Biomedical Sciences, Tshwane University of Technology, 175 Nelson Mandela Drive, Arcadia Campus, Pretoria 0001, South Africa

Cholera remains a problem in developing countries. This is attributed to the unavailability of proper water treatment, sanitary infrastructure and poor hygiene. As a consequence, countries facing cholera outbreaks rely on interventions such as the use of oral rehydration therapy and antibiotics to save lives. In addition to vaccination, the provision of chlorine tablets and hygiene sensitization drives have been used to prevent new cholera infections. The implementation of these interventions remains a challenge due to constraints associated with the cost, ease of use and technical knowhow. These challenges have been reduced through the use of solar water disinfection (SODIS). The success of SODIS in mitigating the risk associated with the consumption of waterborne pathogens has been associated with solar irradiation. This has prompted a lot of focus on the solar component for enhanced disinfection. However, the role played by the host immune system following the consumption of solar-irradiated water pathogens has not received any significant attention. The mode of inactivation resulting from the exposure of microbiologically contaminated water results in immunologically important microbial states as well as components. In this review, the possible influence that solar water disinfection may have on the immunity against cholera is discussed.

A novel point-of-use water treatment method by antimicrobial nanosilver textile material. J Water Health. 2014 Dec;12(4):670-7. doi: 10.2166/wh.2014.197.

Liu H1, Tang X2, Liu Q3. Author information: 1Key Laboratory of Natural Medicine and Immuno-Engineering of Henan Province, Henan University, Kaifeng, Henan 475004, China E-mail: hjliu@henu.edu.cn; AGplus Technologies Pte Ltd, 10 Jalan Besar #10-06 Sim Lim Tower, Singapore 208787.
2AGplus Technologies Pte Ltd, 10 Jalan Besar #10-06 Sim Lim Tower, Singapore 208787.
3School of Architecture and the Built Environment, Singapore Polytechnic, 500 Dover Road, Singapore 139651.

Pathogenic bacteria are one of the main reasons for worldwide water-borne disease causing a big threat to public health, hence there is an urgent need to develop cost-effective water treatment technologies. Nano-materials in point-of-use systems have recently attracted considerable research and commercial interests as they can overcome the drawbacks of traditional water treatment techniques. We have developed a new point-of-use water disinfection kit with nanosilver textile material. The silver nanoparticles were in-situ generated and immobilized onto cotton textile, followed by fixing to a plastic tube to make a water disinfection kit. By soaking and stirring the kit in water, pathogenic bacteria have been killed within minutes. The silver leaching from the kit was insignificant, with values <100 ppb – the current US EPA and WHO limit for silver level in drinking water. Herein, the nanosilver textile water disinfection kit could be a new, efficient and cost-effective point-of-use water treatment method for rural areas and emergency preparedness.