Microbial contamination of drinking water in Pakistan—a review

Water pollution with pathogenic microorganisms is one of the serious threats to human health, particularly in developing countries. The main objective of this article is to highlight microbial contamination of drinking water, the major factors responsible for microbial contamination, and the resulting health problems in Pakistan. Furthermore, this study will be helpful for researchers and administrative agencies to initiate relevant studies and develop new policies to protect further deterioration of water supply with pathogenic microbes and ensure clean and safe drinking water to the public in Pakistan. In Pakistan, water at the source, in the distribution network, and at the consumer tap is heavily polluted with coliforms and fecal coliforms all over the country. An overview of more than 7,000 water samples reviewed here reveals that an average of over 71 and 58 % samples in the country was contaminated with total coliforms and fecal coliforms, respectively. Drinking water contamination accounts for 20 to 40 % of all diseases in the country, which causes national income losses of Rs 25–58 billion annually (US$0.25–0.58 billion, approximately 0.6–1.44 % of the country’s GDP). Improper disposal of industrial and municipal wastes is the most important factor responsible for water pollution in the country followed by cross-contamination due to old and leaking pipes and lack of water filtration and disinfection facilities. There is an urgent need for emergency steps to stop further deterioration of water quality and improve the existing water quality so as to protect the public from widespread waterborne diseases.     

Rapid and long-effective removal of broad-spectrum pollutants from aqueous system by ZVI/oxidants

• The coupling of oxidants with ZVI overcome the impedance of ZVI passive layer. • ZVI/oxidants system achieved fast and long-effective removal of contaminants. • Multiple mechanisms are involved in contaminants removal by ZVI/oxidant system. • ZVI/Oxidants did not change the reducing property of ORP in the fixed-bed system. Zero-valent iron (ZVI) technology has recently gained significant interest in the efficient sequestration of a wide variety of contaminants. However, surface passivation of ZVI because of its intrinsic passive layer would lead to the inferior reactivity of ZVI and its lower efficacy in contaminant removal. Therefore, to activate the ZVI surface cheaply, continuously, and efficiently is an important challenge that ZVI technology must overcome before its wide-scale application. To date, several physical and chemical approaches have been extensively applied to increase the reactivity of the ZVI surface toward the elimination of broad-spectrum pollutants. Nevertheless, these techniques have several limitations such as low efficacy, narrow working pH, eco-toxicity, and high installation cost. The objective of this mini-review paper is to identify the critical role of oxygen in determining the reactivity of ZVI toward contaminant removal. Subsequently, the effect of three typical oxidants (H₂O₂, KMnO₄, and NaClO) on broad-spectrum contaminants removal by ZVI has been documented and discussed. The reaction mechanism and sequestration efficacies of the ZVI/oxidant system were evaluated and reviewed. The technical basis of the ZVI/oxidant approach is based on the half-reaction of the cathodic reduction of the oxidants. The oxidants commonly used in the water treatment industry, i.e., NaClO, O₃, and H₂O₂, can be served as an ideal coupling electron receptor. With the combination of these oxidants, the surface corrosion of ZVI can be continuously driven. The ZVI/oxidants technology has been compared with other conventional technologies and conclusions have been drawn.     

Evaluation of the Swat River,Northern Pakistan,water quality using multivariate statistical techniques and water quality index (WQI) model

Environmental Science and Pollution Research - This study evaluates the characteristics of water along the Swat River, Northern Pakistan. For this purpose, water samples (n = 30) were...     

CO2 separation by supported liquid membranes synthesized with natural deep eutectic solvents

Environmental Science and Pollution Research - Betaine-based natural deep eutectic solvents (NADESs), a new class of green solvents, were immobilized into a porous polyvinylidene fluoride (PVDF)...     

Nexus on climate change: agriculture and possible solution to cope future climate change stresses

The changing climate scenarios harshen the biotic stresses including boosting up the population of insect/pest and disease, uplifting weed growth, declining soil beneficial microbes, threaten pollinator, and boosting up abiotic stresses including harsh drought/waterlogging, extremisms in temperature, salinity/alkalinity, abrupt rainfall pattern)) and ulitamtely  affect the plant in multiple ways. This nexus review paper will cover four significant points viz (1) the possible impacts of climate change; as the world already facing the problem of food security, in such crucial period, climatic change severely affects all four dimensions of food security (from production to consumption) and will lead to malnutrition/malnourishment faced by low-income peoples. (2) How some major crops (wheat, cotton, rice, maize, and sugarcane) are affected by stress and their consequent loss. (3) How to develop a strategic work to limit crucial factors, like their significant role in climate-smart breeding, developing resilience to stresses, and idiotypic breeding. Additionally, there is an essence of improving food security, as much of our food is wasted before consumption for instance post-harvest losses. (4) Role of biotechnology and genetic engineering in adaptive introgression of the gene or developing plant transgenic against pests. As millions of dollars are invested in innovation and research to cope with future climate change stresses on a plant, hence community base adaptation of innovation is also considered an important factor in crop improvements. Because of such crucial predictions about the future impacts of climate change on agriculture, we must adopt measures to evolve crop.

     

Controlling environmental pollution: dynamic role of fiscal decentralization in CO2 emission in Asian economies

Environmental Science and Pollution Research - The “environment” has become one of the important and debatable topics of the world and policymakers identifying the new predictors of CO2...     

Sustainable supplier selection for the cold supply chain (CSC) in the context of a developing country

Cold supply chain (CSC) is a process that involves temperature-controlled activities ranging from the acquisition of raw materials and down to the end consumers. A sustainable cold chain supplier is the one that incorporates sustainable practices in its complete cycle of operations. This is to ensure keeping the products from going to waste, especially in the case of a developing country. To identify the driving factors towards the sustainable cold chain supplier, this study utilizes the interpretive structural modelling (ISM) approach in the first phase. Fifteen various sustainability factors were analyzed and the “utilization of renewable resources” factor concluded to be the most important driving factor. By implementing renewable resources, a supplier can be able to convert its manufacturing processes and services to sustainable assets. The second phase of this study conducts the selection of cold chain suppliers in the context of Pakistan. For this purpose, fuzzy VIKOR, a multi-criteria decision-making (MCDM) technique is incorporated to analyze eight suppliers based on fifteen distinct criteria. The results concluded Mitchell foods to be the most economically, environmentally and socially sustainable suppliers in the context of Pakistan. This study recommends providing business-friendly incentives to suppliers like Mitchells and new investors who tend to keep their operations sustainable by adopting renewable resources. Furthermore, the relaxation of taxes and creating job employability by working with sustainable suppliers can contribute positively towards economic growth and the overall society. The study holds novelty in the area of cold chain supplier selection for Pakistan by utilizing a novel approach in the form of ISM and fuzzy VIKOR techniques, thus forming a major application of this research study.

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Correction to: The trade-off between economic growth and environmental quality: does economic freedom asymmetric matter for Pakistan?

Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-13968-6     

Pharmacological evaluation of crude methanolic extract of Kalanchoe pinnata leaves

Medicinal plants play a crucial role in maintaining human health. Kalanchoe pinnata has been used for treatment of different ailments like infections, rheumatism, and inflammation. Data showed that Kalancho pinnata methanolic extract (100 or 1000 μg/ml) significantly inhibited growth of shoots (hypocotyls) and roots (radicals) of rice compared to control after 3 or 7 days treatment. Further, the Kalancho pinnata methanolic extract (50–1000 μg/ml) exhibited antioxidant properties and scavenged free radicals in dose-dependent manner compared with a standard antioxidant (ascorbic acid). Kalancho pinnata methanolic extract also possesses antifungal property that inhibited approximately 76% and 51% growth of Aspergillus flavous and Aspergillus niger, respectively, using the extract at 200 μg/ml.     

University students’ awareness of e-waste and its disposal practices in Pakistan: a construction of the conceptual framework

Journal of Material Cycles and Waste Management - Pakistan is among the few countries generating and receiving enormous e-waste, which posits a threat to its future generations. A...