Toqeer Ahmed

Emerging nanotechnology-based methods for water purification: a review

AbstractNanotechnology has a wide range of applications. This makes it a very important technology of the future. Its application in water and wastewater purification is of great interest not only in developing countries but also in the developed countries. The application of nanometals (silver and gold) and nanomembranes can help in developing of water treatment technologies which can be used for solving water-related problems such as waterborne pathogens, biofouling, removal of toxic metals (lead, arsenic, and chromium), etc. Moreover, nanotechnology can also be used to increase the efficiency of water filters. In this paper, we review the emerging nanotechnology-based methods for water purification, the potential applications of nanotechnology in the form of nanosensors, nanomembranes, nanometallic particles, and photocatalysis for water purification, nanosensors for detection of contaminants in water, novel magnetic nanoparticles for water desalination, and finally we present the possible risks associ...

The synergy of permeable pavements and geothermal heat pumps for stormwater treatment and reuse

The use of permeable pavement systems with integrated geothermal heat pumps for the treatment and recycling of urban runoff is novel and timely. This study assesses the efficiency of the combined technology for controlled indoor and uncontrolled outdoor experimental rigs. Water quality parameters such as biochemical oxygen demand, nutrients, total viable heterotrophic bacteria and total coliforms were tested before and after treatment in both rigs. The water borne bacterial community genomic deoxyribonucleic acid (DNA) was analyzed by polymerase chain reaction (PCR) amplification followed by denaturing gradient gel electrophoresis (DGGE) and was further confirmed by DNA sequencing techniques. Despite the relatively high temperatures in the indirectly heated sub‐base of the pavement, potentially pathogenic organisms such as Salmonella spp., Escherichia coli, faecal Streptococci and Legionella were not detected. Moreover, mean removal rates of 99% for biochemical oxygen demand, 97% for ammonia‐nitrogen and 95% for orthophosphate‐phosphates were recorded. This research also supports decision‐makers in assessing public health risks based on qualitative molecular microbiological data associated with the recycling of treated urban runoff.

Assessment of drinking water quality and its potential health impacts in academic institutions of Abbottabad (Pakistan)

AbstractThe continuously deteriorating water quality situation in Pakistan is posing serious health threats to the population. The study aimed to assess the physicochemical and bacteriological quality of drinking water in different institutions of Abbottabad city and its potential health effects on staff and students. About 63 samples from 60 institutions across different locations of Abbottabad city were analysed for physicochemical (temperature, pH, total dissolved solids (TDS) and electrical conductivity (EC)) and bacteriological (total coliforms and Escherichia coli) analysis using standard methods. Water quality (n = 60) and health related (n = 300) information was obtained through pre-designed survey questionnaires. Results showed that all water samples were aesthetically acceptable. In physicochemical analysis, the mean temperature and pH values were found at 27.12 ± 2.47°C and 7.98 ± 0.24, respectively. The mean TDS and EC values were found at 335.42 ± 86.3 ppm and 647.38 ± 174.82 μS, respectively...

Assessment of Antibacterial Activity of Solanum surrattense Against Waterborne Pathogens Isolated from Surface Drinking Water of the Potohar Region in Pakistan

ABSTRACT People dwelling in different cities of the Potohar region, Pakistan, are mostly dependent on surface water for drinking and domestic use. In an attempt to make available potable, safe water, filtration plants were constructed along with dams in the Potohar region. Water samples from these filtration plants were collected and analyzed for total and faecal coliform bacteria as well as for total viable count. Results showed that bacterial indicators of faecal contamination were numerous and significantly greater than World Health Organization recommended guidelines. Accordingly, antibacterial activity of methanolic and aqueous extracts of different parts of Solanum surrattense were assessed in vitro against waterborne pathogens. Fruits exhibited more antibacterial activities at incubation at 37°C than shoots and roots, which showed lowest Minimum Inhibitory Concentration (MIC) and zones of inhibition. These results suggest that plants offer a great potential for purification of drinking water that needs to be explored further because fruit extract of the aforementioned plant can be of practical use against waterborne pathogens.

Water-Related Impacts of Climate Change on Agriculture and Subsequently on Public Health: A Review for Generalists with Particular Reference to Pakistan

Water-related impacts due to change in climatic conditions ranging from water scarcity to intense floods and storms are increasing in developing countries like Pakistan. Water quality and waterborne diseases like hepatitis, cholera, typhoid, malaria and dengue fever are increasing due to chaotic urbanization, industrialization, poor hygienic conditions, and inappropriate water management. The morbidity rate is high due to lack of health care facilities, especially in developing countries. Organizations linked to the Government of Pakistan (e.g., Ministry of Environment, Ministry of Climate Change, Planning and Development, Ministry of Forest, Irrigation and Public Health, Pakistan Meteorological Department, National Disaster Management, Pakistan Agricultural Research Centre, Pakistan Council for Research in Water Resources, and Global Change Impact Study Centre), United Nation organizations, provincial government departments, non-governmental organizations (e.g., Global Facility and Disaster Reduction), research centers linked to universities, and international organizations (International Institute for Sustainable Development, Food and Agriculture, Global Climate Fund and World Bank) are trying to reduce the water-related impacts of climate change, but due to lack of public awareness and health care infrastructure, the death rate is steadily increasing. This paper critically reviews the scientific studies and reports both at national and at international level benefiting generalists concerned with environmental and public health challenges. The article underlines the urgent need for water conservation, risk management, and the development of mitigation measures to cope with the water-related impacts of climate change on agriculture and subsequently on public health. Novel solutions and bioremediation methods have been presented to control environmental pollution and to promote awareness among the scientific community. The focus is on diverse strategies to handle the forthcoming challenges associated with water resources management.

Assessment of Antibacterial Activity of Colebrookia oppositifolia against Waterborne Pathogens Isolated from Drinking Water of the Pothwar Region in Pakistan

ABSTRACT An attempt was made to control waterborne pathogens by using medicinal plant extracts. One hundred and twenty-six water samples from filtration plants, tube wells, and water supplies were collected and analyzed for total and faecal Coliform bacteria as well as for total viable count. Results showed that waterborne pathogens were numerous and significantly higher than the World Health Organizations recommended guidelines. The methanolic and aqueous extracts of different parts of Colebrookia oppositifolia (Labiateae) were examined for antibacterial activities in vitro by an agar diffusion method. Antibacterial activity of leaves, shoots, and roots of Colebrookia oppositifolia was assessed against Gram positive and Gram negative bacteria that were isolated and identified from water samples by the API 20E method. Extract of roots showed more antibacterial activities against Staph. aureus and B. cereus var. mycoides, Pseudomonas aeruginosa, Klebsiella pneumonia, and Shigella flexneri at 37°C, than extracts from leaves and shoots. The lowest MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) were observed in roots as compared to shoots and leaves. These results suggest that there is an urgent need for improvement in existing water quality treatment. Secondly, the fruit extract can be practical for protection and to avoid risk of contamination by waterborne pathogens and to promote indigenous solutions for disease-control and environmental management.

A GIS mapping assessment of the suitability of the Oued Rmel aquifer for irrigation in the Zaghouan district (north-eastern Tunisia)

A total of twenty-three water samples were collected in winter 2013 to assess groundwater quality in the Oued Rmel aquifer in the Zaghouan governate in Tunisia. These samples were subject to in-field measurements of some physico-chemical parameters (temperature, pH, and salinity), and laboratory analysis of major elements. Several parameters were used to assess the quality of water destined for irrigation, including electrical conductivity (EC) and sodium adsorption ratio (SAR). As part of this work, GIS was used to study spatial distributions of SAR, EC, residual sodium carbonate, sodium percentage (%Na), Doneen’s permeability index, Kelly’s ratio, and magnesium hazard and, therefore, evaluated the water quality of Oued Rmel (good, fair, or poor) regarding irrigation. The major ions most abundantly found in the waters of Oued Rmel were in the following order: Na+ > Ca2+ > Mg2+ > K+ and Cl− > SO42− > HCO3. 56% of water samples from the Oued Rmel aquifer showed a low alkalinization risk, where SAR was lower than 10, 39% have a medium soil destabilization risks (10 < SAR < 18), and just 5% indicated high alkalinity hazards (SAR > 26). Samples of water intended for irrigation showed a medium to high sodicity and alkalinization risk. It is expected that output may help in assessing the impacts of water quality of the Oued Rmel aquifer used for irrigation.

Elucidation of Emerging Nanomaterials Impacts on Antibiotic Resistance Against Soil and Aquatic Microflora

Antibiotic resistance is becoming a big challenge in almost all the fields especially against soil microflora. With the advent and spread of emerging metallic nanomaterials (MNPs), it is important to elucidate the optimistic and adverse impacts on plants and soil microflora along with the positive use of antibiotics. It is well known that green synthesis of nanomaterials has antimicrobial properties and cytotoxic to the harmful bacteria and enhances the properties of antibiotics, but applications of nanomaterials in the soil environment is a big interrogation due to their inhibitory effects on plant’s growth enzymes and plant’s beneficial bacteria. Impacts of nanomaterials in combination with antibiotics and their role on plant growth-promoting bacteria have been discussed in this chapter. Further, the use of nanomaterials in soil, their role in sorption by plants, their access to food web, and impacts on human health are critically discussed. Finally, some more studies regarding a missing gap for the use of MNPs against plant’s beneficial bacteria are recommended.

Biodeterioration of buildings and public health implications caused by indoor air pollution

Biodeterioration challenges range from poor indoor air quality and exterior marble defacing to more dangerous building degradation. People often change the look of degraded walls by painting over them, removing carpets as well as replacing damaged wood and papers to improve their aesthetic value. Due to a lack of public awareness and health care infrastructure, the degradation rate is increasing in many countries. There is a need for a review of the international literature supporting practical recommendations. In this critical review paper, the role of microbes in deteriorating buildings, their health impacts in terms of mycotoxins and diverse strategies to handle them are discussed. Moreover, the forthcoming challenges associated with biodegradation and their health impacts have been addressed. Key recommendations have been made: (a) increase of awareness due to community involvement in enhancing moisture control, (b) improvement of cleaning processes and the use of air conditioning systems, (c) regular inspection and maintenance regimes for buildings and (d) cleaning of heating and air conditioning units and associated replacements of filters. The review provides a broad overview of the subject area and should be of interests to generalists working in a wide range of disciplines relevant to indoor air quality.

Evaluation and Risk Management by Using Ocimum bacillicum Against Waterborne Pathogens

ABSTRACT Food and medicinal plants have been used for centuries against human diseases. The methanolic and aqueous extracts of different parts of Ocimum bacillicum Lam. (Niazboo or Sweet basil) of family Lamiaceae were investigated in vitro for their antibacterial properties against waterborne pathogens. The antibacterial properties of different parts of Ocimum bacillicum samples were assessed against Gram positive and Gram negative bacteria, which were isolated from water samples and identified by the API 20E method. The extracts from leaves and seeds of Ocimum bacillicum showed more antibacterial activities against Staphylococcus aureus, Pseudomonas aeruginosa, and E. coli at 37°C than those obtained from shoots, roots, and buds. The lowest minimum inhibitory concentrations and minimum bactericidal concentrations were observed for leaves and seeds as compared to other parts of the plant. No activity of alum was observed against the tested bacterial strains. The seeds of Ocimum bacillicum were associated with higher coagulation activity in comparison to other parts of the plant and were comparable with alum. These results suggest that parts of a plant offer a potential for antimicrobial treatment of drinking water, but needs further exploration.