Hydraulic conductivity and swelling pressure of GCLs using polymer treated clays to high concentration CaCl(2) solutions

A Geosynthetic Clay Liner (GCL) is a frequently used h ydraulic barrier system designed to impede the flow of contaminated leachate into the environment. The main objective of this barrier system is to maintain a low hydraulic conductivity that is determined by the bentonite fraction. In this study, calcium bentonite, natural sodium bentonites, and sodium activated bentonite were treated with the HYPER clay technique. This involves the adsorption of an anionic polymer, Sodium CarboxyMethylCellulose (Na-CMC) onto the surface of the clay material. The purpose of this research was to show the beneficial effect of the HYPER clay treatment on the swelling and hydraulic performance, while the bentonite is permeated with high concentration CaCl2 solutions. The test results showed that swelling and hydraulic performance increased with Na-CMC treatment, regardless of the type of bentonite that was used. Additionally, a powdered Na CMC configuration provided higher swelling and hydraulic performance compared to a granular configuration

Effectiveness of a home-environmental intervention package and an early child development intervention on child health and development in high-altitude rural communities in the Peruvian Andes: a cluster-randomised controlled trial

Unsafe drinking water, poor sanitation and hygiene, exposure to household air pollution and low cognitive and socio-emotional stimulation are risk factors affecting children in low- and middle-income countries. We implemented an integrated home-environmental intervention package (IHIP), comprising a kitchen sink, hygiene education and a certified improved biomass cookstove, and an early child development (ECD) programme to improve children´s health and developmental outcomes in the rural high-altitude Andes of Peru

Improving household air, drinking water and hygiene in rural Peru : a community-randomized-controlled trial of an integrated environmental home-based intervention package to improve child health

Diarrhoea and acute lower respiratory infections are leading causes of childhood morbidity and mortality, which can be prevented by simple low-cost interventions. Integrated strategies can provide additional benefits by addressing multiple health burdens simultaneously.; We conducted a community-randomized-controlled trial in 51 rural communities in Peru to evaluate whether an environmental home-based intervention package, consisting of improved solid-fuel stoves, kitchen sinks, solar disinfection of drinking water and hygiene promotion, reduces lower respiratory infections, diarrhoeal disease and improves growth in children younger than 36 months. The attention control group received an early child stimulation programme.; We recorded 24 647 child-days of observation from 250 households in the intervention and 253 in the attention control group during 12-month follow-up. Mean diarrhoea incidence was 2.8 episodes per child-year in the intervention compared with 3.1 episodes in the control arm. This corresponds to a relative rate of 0.78 [95% confidence interval (CI): 0.58-1.05] for diarrhoea incidence and an odds ratio of 0.71 (95% CI: 0.47-1.06) for diarrhoea prevalence. No effects on acute lower respiratory infections or children's growth rates were observed.; Combined home-based environmental interventions slightly reduced childhood diarrhoea, but the confidence interval included unity. Effects on growth and respiratory outcomes were not observed, despite high user compliance of the interventions. The absent effect on respiratory health might be due to insufficient household air quality improvements of the improved stoves and additional time needed to achieve attitudinal and behaviour change when providing composite interventions

Household-level risk factors for water contamination and antimicrobial resistance in drinking water among households with children under 5 in rural San Marcos, Cajamarca, Peru

Household water contamination at point of use depends on human, animal and environmental factors embodying all aspects of a One Health approach. This study investigated the association between household factors, the presence of thermotolerant coliform, and the presence of antibiotic resistant bacteria in drinking water among 314 households with children under 5 in Cajamarca, Peru. This study analysed data from a baseline sampling of a randomized controlled trial, including household surveys covering household water management and factors such as household animals, as well as microbiological data from samples collected from drinking water. Data were analysed using generalized linear models. Drinking water samples collected from narrow-mouthed containers were less likely to be contaminated than samples collected from the faucet (OR = 0.55, p = 0.030) or wide mouthed containers. The presence of thermotolerant coliform was associated with owning farm birds, which increased the proportion of contamination from 42.2% to 59.1% (OR = 1.98, p = 0.017) and with animal waste observed in the kitchen area, which increased the prevalence of contamination from 51.4% to 65.6% (OR = 1.80, p = 0.024). Resistance to any antibiotic was higher among pig owners at 60%, relative to non-pig owners at 36.4% (OR = 1.97, p = 0.012) as well as households with free-roaming animals in the kitchen area at 59.6% compared to households without free-roaming animals at 39.7% (OR = 2.24, p = 0.035). Recent child antibiotic use increased the prevalence of trimethoprim-sulfamethoxazole resistance among E. coli isolates to 22.3% relative to 16.7% (OR = 3.00, p = 0.037). Overall, these findings suggest that water storage in a secure container to protect from in-home contamination is likely to be important in providing safe drinking water at point of use. In addition, transmission of thermotolerant coliform and AMR between domestic animals and human drinking water supplies is likely. Further research should explore transmission pathways and methods to support safe drinking water access in multi-species households

Acceptance and uptake of improved biomass cookstoves in Peru: learning from system level approaches to transform large-scale cooking interventions

Improved biomass cookstoves (ICS) are cooking technologies that increase wellbeing and reduce household air pollution. With the goal of identifying factors influencing ICS acceptance and uptake at five system levels (intrapersonal, interpersonal, community, institutional, and policy), we carried out a qualitative study in three regions in Peru. We conducted 32 focus group discussions (243 ICS users) and 26 semi-structured interviews with key stakeholders, applying a combination of two system-level frameworks for analysis: the socio-ecological model and the ICS adoption domain. Enabling and impeding factors at each level were closely related to each other. Decisions made by policy makers - often centralised and not considering local/regional realities - strongly influenced acceptance and barriers at lower levels. ICS acceptance and uptake tended to be low when ICS users were not involved from the start. Most ICS programmes focused on stove distribution outputs, without considering community needs, such as training on ICS building, maintenance and repair, or issues related to spare part availability, which is a strong barrier to sustained uptake of ICS. Using a combination of models that allows one to examine facilitators and barriers at multiple levels, as well as the interactions of those levels, was useful in assessing potential improvements to intervention design, facilitating programme success, preventing unforeseen programme adaptations, and improving cost-effectiveness of interventions

Antimicrobial resistance in humans, animals, water and household environs in rural Andean Peru: exploring dissemination pathways through the One Health lens

Antimicrobial resistance (AMR) is a global public health threat, especially for low and middle-income countries (LMIC) where the threat has not been fully identified. Our study aims to describe E. coli AMR in rural communities to expand our knowledge on AMR bacterial contamination. Specifically, we aim to identify and describe potential dissemination routes of AMR-carrying bacteria in humans (children's stools), community water sources (reservoirs and household sources), household environments (yard soil) and domestic animals of subsistence farmers in rural Andean areas. Our cross-sectional study was conducted in rural households in the region of Cajamarca, Peru. A total of 266 samples were collected. Thirty-four point six percent of reservoir water and 45% of household water source samples were positive for thermotolerant coliforms. Of the reservoir water samples, 92.8% were positive for E. coli, and 30.8% displayed resistance to at least one antibiotic, with the highest resistance to tetracycline. E. coli was found in 57.1% of the household water sources, 18.6% of these isolates were multidrug-resistant, and displayed the highest resistance to tetracycline (31.3%). Among samples from the children's drinking water source, 32.5% were positive for thermotolerant coliforms, and 57.1% of them were E. coli. One third of E. coli isolates were multidrug-resistant and displayed the highest AMR to tetracycline (41.6%) and ampicillin (25%). Thermotolerant coliforms were found in all the soil samples, 43.3% of the isolates were positive for E. coli, 34.3% of the E. coli isolates displayed AMR to at least one antibiotic, and displayed the highest AMR to tetracycline (25.7%). We determined thermotolerant coliforms in 97.5% of the child feces samples; 45.3% of them were E. coli, 15.9% displayed multidrug resistance, and displayed the highest resistance to ampicillin (34.1%). We identified thermotolerant coliforms in 67.5% of the animal feces samples. Of those, 38.7% were E. coli, and 37.7% were resistant to at least one antibiotic. For all the samples, the prevalence of resistance to at least one antibiotic in the E. coli and Klebsiella spp. isolates was almost 43% and the prevalence of MDR in the same isolates was nearly 9%, yet the latter nearly doubled (15.9%) in children's stools. Our results provide preliminary evidence for critical pathways and the interconnectedness of animal, human and environmental transmission but molecular analysis is needed to track dissemination routes properly

Evaluación de un método para la detección de plaguicidas anticolinesterasa en subproductos de la refinación de aceite.

Los plaguicidas anticolinesterasa, o inhibidores de colinesterasas son compuestos químicos que inhiben a las enzimas colinesterasas impidiendo que se destruya la acetilcolina liberada, produciendo como consecuencia un aumento en la concentración y en la duración de los efectos del neurotransmisor. Entre los mas usados para el control de las plagas se encuentran los organofosforados y carbamatos y pueden contaminar agua, suelo y tener permanencia en los alimentos. Productos contaminados pueden llegar al consumidor, por lo que seria muy util un método para la detección rapida de estos compuestos. En el presente estudio, se llevó acabo la detección de inhibidores de colinesterasas por del método Ellman, que se basa en la actividad enzimática de la acetilcolinesterasa (AChE). Se elaboro un extaracto enzimatico AChE a partir de subproducto de cabezas de pescado y se estandarizo la concentración de extracto que mostró actividad lineal durante cinco minutos. Como inhibidor de AChE se utilizó el organofosforado diazinon a diferentes concentraciones. Se evaluó el efecto de solventes lipidicos a utilizar, seleccionando el etanol al 10%. Finalmente, se ensayaron cuatro muestras de subproductos de la refinación de aceite de soya, solas y con adición de diazinon para detectar inhibidores de colinesterasas. El porcentaje de inhibición fue expresado como equivalentes de diazinon. El método fue sensible por lo que podría ser implementado en el análisis de alimentos