A perspective review on medicinal plant resources for their antimutagenic potentials

Environmental Science and Pollution Research - Mutagens present in the environment manifest toxic effects and are considered as serious threat for human health and healthcare. Recent reports reveal...     

Environmental challenge vis a vis opportunity: the case of water hyacinth

Water hyacinth (Eichhornia crassipes) is a noxious weed that has attracted worldwide attention due to its fast spread and congested growth, which lead to serious problems in navigation, irrigation, and power generation. On the other hand, when looked from a resource angle, it appears to be a valuable resource with several unique properties. As a result, research activity concerning control (especially biological control) and utilization (especially wastewater treatment or phytoremediation) of water hyacinth has boomed up in the last few decades. Investigations on biogas/compost production from water hyacinth have also come up very well mainly from few research groups in India. This review presents a comprehensive view of the research related to water hyacinth with special emphasis on the recent investigations on water hyacinth control and utilization technologies conducted in the last 2-3 decades. Based on these significant research achievements, now it is desirable to identify a management strategy so that the excessive growth can be controlled and the plant can be used in beneficial ways. In the rural areas, water hyacinth could be used in an integrated manner for decentralized wastewater treatment systems coupled to biogas and compost production from the resulting biomass. There is a need to work out the techno-economic viability of such integrated model systems.     

Levels and distribution of persistent organochlorine pesticide residues in water and sediments of Gomti River (India)—a tributary of the Ganges River

This study reports the concentration levels and distribution pattern of the persistent organochlorine pesticide (OCPs) residues in the water and bed-sediments of the Gomti River collected seasonally over a period of 2 years. The water and bed-sediment samples were collected from eight different sites and analyzed for aldrin, dieldrin, endrin, HCB, HCH isomers, DDT isomers/metabolites, endosulfan isomers (alpha and beta), endosulfan sulfate, heptachlor and its metabolites, alpha-chlordane, gamma-chlordane and methoxychlor. In the river water and sediments SigmaOCPs residues ranged between 2.16 and 567.49 ng l(-1) and 0.92 and 813.59 ng g(-1), respectively. The results, further, suggested that source of DDT contamination is from the aged and weathered agricultural soils with signature of recently used DDT in the river catchments. To assess any adverse effect of OCPs contamination on river's biological component, the threshold effect level (TEL) was used. The results revealed that bed-sediments of the Gomti River are contaminated with lindane, endrin, heptachlor epoxides and DDT, particularly at site-4 and may contribute to sediment toxicity in the freshwater ecosystem of the river.     

Development of controlled release formulations of carbofuran and imidacloprid and their bioefficacy evaluation against aphid,Aphis gossypii and leafhopper,Amrasca biguttula biguttula Ishida on potato crop

Controlled release (CR) formulations of carbofuran and imidacloprid were prepared employing polyvinyl chloride and carboxymethyl cellulose (CMC) and their bioefficacy was evaluated against the aphid, Aphis gossypii and leafhopper, Amrasca biguttula biguttula Ishida on potato crop. The CR formulations of carbofuran and imidacloprid provided better or equal control of the pests than commercial formulations. CMC-based formulation provided a superior control of both the pests. The Imida-CMC, which showed the lowest population of leaf hopper (10.50 leafhopper/100 cl), provided significantly superior control among all treatments after 35 days after germination (DAG). The residue of carbofuran and imidacloprid in potato tuber and soils were not detectable at the time of harvesting in any one of the formulations.     

Mutagenicity and genotoxicity assessment of industrial wastewaters

The genotoxicity of industrial wastewaters from Jajmau (Kanpur), was carried out by Ames Salmonella/microsome test, DNA repair-defective mutants, and Allium cepa anaphase–telophase test. Test samples showed maximum response with TA98 strain with and without metabolic activation. Amberlite resins concentrated wastewater samples were found to be more mutagenic as compared to those of liquid–liquid extracts (hexane and dichloromethane extracts). The damage in the DNA repair defective mutants in the presence of Amberlite resins concentrated water samples were found to be higher to that of liquid–liquid-extracted water samples at the dose level of 20 μl/ml culture. Among all the mutants, polA exhibited maximum decline with test samples. Mitotic index (MI) of root tip meristematic cells of A. cepa treated with 5, 10, 25, 50, and 100 % (v/v) wastewaters were significantly lower than the control. Complementary to the lower levels of MI, the wastewaters showed higher chromosomal aberration levels in all cases investigated.     

Overcoming growing water scarcity: Exploring potential improvements in water productivity in India

Improvements in water productivity (WP) are often suggested as one of the alternative strategies for overcoming growing water scarcity in India. This paper explores the potential improvements in WP of food grains at district level, which currently varies between 0.11 and 1.01 kilogram per cubic metre (kg/m³), in the 403 districts that account for 98% of the total production of food grains. The paper first finds the maximum yield function conditional on consumptive water use (CWU) and then explores the potential improvements in WP by: (a) bridging the gap between actual and maximum yield while keeping CWU constant; and (b) changing the maximum yield by adjusting the CWU using supplementary or deficit irrigation. Deficit irrigation in some areas may decrease yield but can increase production if land availability is not a constraint. A large potential exists for bridging the yield gap in irrigated areas with CWU between 300 and 475 mm. Of the 222 districts that fall under this category, a 50% reduction in yield gap alone could increase production by 100 million tonnes (Mt) without increasing CWU. Supplementary irrigation can increase yield and WP in rain‐fed and irrigated areas of 266 and 16 districts with CWU is below 300 mm. Deficit irrigation in irrigated areas of 185 districts with CWU above 475 mm could increase yield, WP and production. Decreasing CWU in irrigated areas with CWU between 425 and 475 mm reduces yield slightly, but if availability of land is not a constraint then the benefits due to water saving and production increases could exceed the cost.     

Measurement and Modelling of Ammonia Emissions at Waste Treatment Lagoon-Atmospheric Interface

Global emissions of ammonia are approximately 75 Tg N/yr (1 Tg =10¹²g). The major global source is excreta from domestic animals ( 32 Tg N ^-1yr^-1). Waste storage and treatment lagoonsare used to treat the excreta of hogs in North Carolina (NC). Proteins and nitrogen rich compounds in the lagoon are convertedto ammonia, through a series of biological and chemical transformations. The process of ammonia emission has been investigated using two different model approaches: (1) CoupledMass Transfer with Chemical Reaction Model (Model I), and (2)Mass Transport without Chemical Reaction Model (Model II). Asensitivity analysis is performed with the models, and the modelresults are compared with ammonia emission experiments at a swinewaste storage and treatment lagoon in NC using a dynamic emissionflux chamber.Results of model predictions of emission flux indicate an exponential increase in ammonia flux with increasing lagoontemperature and pH, a linear increase with increasing lagoontotal ammoniacal nitrogen (TAN), and a secondary degree increasewith the increasing wind speed. In addition, the fluxes predictedby Model I are consistently larger than fluxes predicted by Model II. Experimental values of flux agreed well with model predictions, with the experimental values lying in different positions between the two model predictions under different physical and chemical conditions. Further, when compared to diurnal and seasonal experimental flux values, Model I corroborates the results in calm meteorological conditions (windspeed U10 = 1.5 m s^-1). However, the observed results are better predicted by Model II during unstable conditions, when wind speeds are higher than 2.0 m s^-1 and physical transfer process functions dominate.