Determination of appropriate service quality attributes for household toilets in rural settlements of India based on user perception

In many developing countries, including India, governments have implemented programs for improvement of environment and health in rural settlements through the provision of a subsidized household toilet with specifications selected and benchmarked from the experts’ perspective with only partial consideration of users’ perception. Provision of household toilets with specifications or service quality as perceived by users is a requirement for the sustainability and sustained use of toilet infrastructure. Users do not judge only the overall quality of a service but also base their judgment on a few attributes which are either perceived to be relatively more important or where there is a wider gap between expectation and perception . This paper presents a review of the service quality attributes of the household toilet as found in the relevant literature and provides a step-by-step approach for identifying appropriate attributes based on users’ perspective. While an initial list of attributes was developed based on literature review, initial selection and modifications of the attributes’ definition and units were carried out as per our judgment. This list was further modified through focus groups discussions and incorporating expert opinions. The final list of attributes is selected based on the stated importance level of attributes as perceived by users. The study finds that the attributes prioritized by the users are different from the experts. While government policies emphasize on the construction of toilet, maintenance of toilet is found an important issue for the users.     

Investigating the relationship between lead speciation and bioaccessibility of mining impacted soils and dusts

Environmental Science and Pollution Research - Lead (Pb) bioaccessibility measurements have been the subject of much research in recent years, given the desire to develop a cost-effective and...     

Assessing the chemical behavior and spatial distribution of yttrium and rare earth elements (YREEs) in a coastal aquifer adjacent to the Urmia Hypersaline Lake,NW Iran

This study aims to shed light on the seasonal behavior of yttrium and rare earth elements (YREEs) in the Urmia Aquifer (UA), in the immediate vicinity of Urmia Lake (UL) in Iran. Samples of groundwater, collected under dry and wet conditions in coastal wells of UA, suggest a large degree of variability in both YREE abundance and normalized patterns. Although weathering or water-rock interactions (between the surface/groundwater and rock samples) were predicted to be the most probable source in explaining YREEs in groundwater samples, results to the contrary indicate that the groundwater do not inherit aquifer rock-like YREE signatures in the study area; this might be due to the relative stability of YREEs during the process of water-rock interactions, which suggest that methods based on YREEs can be beneficial in discrimination of water sources. Furthermore, findings demonstrated no significant relationship between Ce/Ce* and salinity (0.08 and 0.05 in wet and dry seasons, respectively), and between Eu/Eu* and salinity (0.1 and ?0.04 in wet and dry seasons, respectively). Dissimilarity of patterns of YREEs in rock and water samples reveals YREEs as no conservative tracers in determining the UL saltwater intrusion into coastal groundwater. Therefore, the groundwater YREE concentrations and fractionation patterns in UA warrant controlling by coastal aquifer need to be controlled by other chemical weathering, adsorption, desorption, and solution complexation reactions. Finally, comparison of REE concentration values in groundwater samples with corresponding indicative admissible drinking water concentrations (IAC) demonstrated their suitability for drinking purposes.

     

Mapping air quality zones for coastal urban centers

This study presents a new method that incorporates modern air dispersion models allowing local terrain and land–sea breeze effects to be considered along with political and natural boundaries for more accurate mapping of air quality zones (AQZs) for coastal urban centers. This method uses local coastal wind patterns and key urban air pollution sources in each zone to more accurately calculate air pollutant concentration statistics. The new approach distributes virtual air pollution sources within each small grid cell of an area of interest and analyzes a puff dispersion model for a full year’s worth of 1-hr prognostic weather data. The difference of wind patterns in coastal and inland areas creates significantly different skewness (S) and kurtosis (K) statistics for the annually averaged pollutant concentrations at ground level receptor points for each grid cell. Plotting the S-K data highlights grouping of sources predominantly impacted by coastal winds versus inland winds. The application of the new method is demonstrated through a case study for the nation of Kuwait by developing new AQZs to support local air management programs. The zone boundaries established by the S-K method were validated by comparing MM5 and WRF prognostic meteorological weather data used in the air dispersion modeling, a support vector machine classifier was trained to compare results with the graphical classification method, and final zones were compared with data collected from Earth observation satellites to confirm locations of high-exposure-risk areas. The resulting AQZs are more accurate and support efficient management strategies for air quality compliance targets effected by local coastal microclimates.

Implications: A novel method to determine air quality zones in coastal urban areas is introduced using skewness (S) and kurtosis (K) statistics calculated from grid concentrations results of air dispersion models. The method identifies land–sea breeze effects that can be used to manage local air quality in areas of similar microclimates.     

A charge model for household waste management services: a case study of Tehran municipality

In practice, it is difficult to implement Pay-As-You-Throw charge systems based on accurate estimates of waste generation. In many cities, this is made impossible, due to lack of technical and administrative infrastructure and cultural considerations, especially in developing countries. This paper presents an alternative two-component charge model that is the combination of cost-accounting technique of Waste Management Services (WMSs) and econometric functions of waste generation. Practical and computation steps considered by the model are presented as a proposal to reform the current system of waste charge in Tehran municipality. The presented model is simple to implement and resolves some of the disadvantages of the traditional methods of waste charge systems, including insufficient revenue to cover the cost of waste management and unfairness related to social inequality.     

Elemental composition of particulate matters around Urmia Lake,Iran

Atmospheric particulate matters and their elements were concurrently measured at two sites located in the north and southeast parts of Urmia Lake from January to September 2013. At both sampling sites, average concentrations of total suspended particulate, particles with the aerodynamic diameter of smaller than 10 µm, smaller than 2.5 µm, and smaller than 1 µm were 260 ± 106, 180 ± 73, 30 ± 8, and 25 ± 7 µg m^?3, respectively. The analyzed water soluble ions accounted for approximately 11%–13% mass concentrations of total suspended particulate and 8%–9% of particles smaller than 10 µm, and the sum of the concentrations of the analyzed elements associated with both ranged from 9 to 41 µg m^?3 (6.5%–9.6% in mass) and 7 to 26 µg m^?3 (5.5%–11.3% in mass), respectively. Thus, particulate matter was composed of a complex mixture of minerals such as halite, quartz, gypsum, hexahydrite, and Bassanite.     

Genotoxicity study of high aspect ratio silver nanowires

The genotoxicity potential of silver nanowires synthesized via the solution-based polyol method has been investigated. They were found to be non-mutagenic in three Salmonella strains and were not genotoxic in a clastogenicity assay in mice. Residual surfactant was found to have an effect on the toxicological properties of the nanowires by increasing the rate of Ag⁺ release. Residual surfactant can be easily degraded via a UV treatment.     

Novel Bioactive Chiral Poly(amide–imide)s Containing Different Amino Acids Linkages: Studies on Synthesis, Characterization and Biodegradability

In this paper chiral bioactive poly(amide–imide)s (PAI)s were synthesized from four different diacids containing chiral amino acids with 4,4′-methylene bis(3-chloro 2,6-diethylaniline) as a diamine via direct polycondensation reaction in a system of tetra-n-butylammonium bromide and triphenyl phosphite as a condensing agent. The structures of these polymers were confirmed by FT-IR, ¹H-NMR, specific rotation, elemental and thermogravimetric analysis (TGA) techniques. TGA showed that the 10 % weight loss temperature in a nitrogen atmosphere was more than 378 °C, which indicates that the resulting PAIs have a good thermal stability. The biodegradability of the monomers and prepared polymers was investigated in culture media and soil burial test for assessment of the susceptibility of these compounds to microbial degradation. The results showed that the synthesized monomers and theirs derived polymers are biologically active and nontoxic to microbial growth.     

Development of composting process of oil palm industrial wastes by multi-enzymatic fungal system

There is an increased interest in composting as an effective means of handling large amounts of organic wastes generated by oil palm industries in Malaysia. However, very few studies have been conducted to develop an effective composting process using the multi-enzymatic system. This study demonstrates an effective composting process of EFB (empty fruit bunch) with POME (palm oil mill effluent), using the optimized process parameters and compatible multi-enzymatic fungal system. A higher decrease (3 %) of organic matter was achieved in the fungal treated system, almost double that of the control (without inoculum). The lowest C/N ratio and soluble protein content recorded were about 17 and 128.82 g/kg, respectively. The maximum germination index obtained was 116 % at day 50 of treatment, which is considered high compared to the control (uninoculated). Furthermore, the maximum activity of ligninase enzyme was found to be 25.95 U/g and the highest cellulase activity was recorded at 0.975 U/g.     

Effect of fungicides on plant growth promoting activities of phosphate solubilizing Pseudomonasputida isolated from mustard (Brassica compestris) rhizosphere

This study was navigated to examine the effects of fungicide-stress on the activities of plant-growth-promoting rhizobacterium Pseudomonasputida with inherent phosphate solubilizing activity. The fungicide-tolerant and phosphate solubilizing P.putida strain PS9 was isolated from the mustard rhizosphere and tentatively identified following standard morphological, physiological and biochemical tests. To further consolidate the identity of the strain PS9, the 16S rDNA sequence analysis was performed. Following the BLAST program, the strain PS9 was identified as P.putida. In the presence of the varying concentrations (0-3200 μg mL⁻¹; at a two fold dilution interval) of four fungicides of different chemical families (tebuconazole, hexaconazole, metalaxyl and kitazin) amended in minimal salt agar medium, the P.putida strain PS9 showed a variable tolerance levels (1400-3200 μg mL⁻¹) against the tested fungicides. The strain PS9 produced plant-growth-promoting (PGP) substances in significant amount in the absence of fungicides. In general, fungicides applied at the recommended, two and three times of the recommended rates, decreased the PGP attributes of P.putida the strain PS9 and affected the PGP activities in concentration-dependent manner. Fungicides at the recommended dose had minor reducing effect while the doses higher than the recommended dose significantly reduced the PGP activities (phosphate solubilization, salicylic acid, 2,3-dihydroxy benzoic acid, and indole-3-acetic acid production except exo-polysaccharides, hydrogen cyanate and ammonia production). Of the four fungicides, tebuconazole generally, showed maximum toxicity to the PGP activities of the strain PS9. This study inferred that fungicides must be examined in vitro for their possible adverse effects on soil micro flora before their application in agricultural fields. Moreover, the results also suggested the prerequisite of application of fungicide-tolerant PGPR strains as bioinoculants so that their PGP activities may not be suppressed under fungicide stress.